Orange Quark

A Brand Spanking New Blog

2005-07-18T08:09:00.000-04:00

As promised on Friday, I have exciting news to announce. Today sees the launch of a new group blog - Cosmic Variance.

My esteemed new co-contributors are; Sean Carroll (of the widely-read Preposterous Universe) - another particle cosmologist; Risa Wechsler, who is a cosmologist from the University of Chicago, Clifford Johnson - a string theorist from the University of Southern California, and JoAnne Hewett - a particle phenomenologist from the Stanford Linear Accelerator Center.

We've been planning for the last month or so, discussing in secret and designing the site in a restricted test area protected by the highest security (well, Risa's excellent computer skills at any rate). We were going to have Karl Rove leak the blog's existence to create a buzz, but he was busy with other, more treasonous leaks.

If you have read Orange Quark more than once, you'll already have a reaasonable idea of the kinds of issues I will be addressing on the new blog - science, science and society, science and politics, what it's like to be a scientist, plus smaller amounts of whatever takes my fancy. The other authors will all have their own voices and interests, although I fully expect the fact that we are all physicists will provide a central theme for the blog.

For now, I'm going to leave open the possibility that I will continue to post here also. However, realistically, I can imagine that time constraints will mean that pretty soon I will focus exclusively on Cosmic Variance. Even if I do cease active posting here, I'll still leave this site up so that, if needed, I can link to previous posts.

I'm excited about the new blog and the cosmo-particle-stringy rabble with whom I'm consorting. If you take a look, please let us know what you think.

Exciting News on the Way

2005-07-15T13:18:00.000-04:00

I'm still traveling and not able to provide significant posts. I did, however, want to post a quick heads up that on Monday I will be announcing some exciting blog news right here. Hope you'll come back to see what it is.

Nuclear Physics, Cosmology and a Gordon Conference

2005-07-11T19:59:00.000-04:00

I leave in the morning to spend a few days at the 2005 Nuclear Physics Gordon Conference. The Gordon Conferences are relatively small, intimate meetings, designed (so I'm told, having not attended one before) to facilitate discussion of cutting edge topics. They are typically held in small colleges all over New England, and the one that I'm attending is happening at Bates College in Lewiston, Maine.

It'll be interesting to be at a nuclear physics conference, since I don't typically attend them. I'm going to this one to give an invited talk titled "Connecting Fundamental Physics and Cosmology". This is the talk I often give to audiences predominantly composed of particle physicists, in which I discuss the issues raised by the energy budget of the universe, discovered through increasingly accurate observations over the last decade. I talk about dark matter, dark energy and the baryon asymmetry of the universe.

As I've mentioned before, the story with dark matter is a particularly interesting example of how microphysics and macrophysics - particle physics and cosmology - can work together to help explain one of the most fundamental questions about reality. If we're lucky, our colliders will discover the properties of new particles, which, with the help of data from dark matter detection experiments, may be identified as twenty percent of the missing matter content of the universe.

There is an interesting precedent for this connection, and it has a nice tie in with nuclear physics. In work beginning in the 1940s and continuing up to the present day, physicists have been able to use well-established nuclear physics data in the context of an expanding spacetime, to understand the abundances of the light elements in the early universe. This prediction of the hot big bang theory, and its remarkable confirmation through precision measurements of primordial Deuterium, Helium-3, Helium-4 and Lithium abundances, is one of the most stunning pieces of evidence supporting our modern cosmological model. Primordial nucleosynthesis (or Big Bang Nucleosynthesis (BBN)), as this process is known, thus provides a compelling template for other cosmo-particle connections, such as the search for dark matter.

Given this rich history of the interplay between nuclear physics and cosmology, I expect to feel quite comfortable as a cosmologist at a nuclear physics conference. In fact, such interplay is not just historical. I'm looking forward to learning a little more about how nuclear physics can help us understand more about supernovae, neutron stars and neutrino physics, and even how the Relativistic Heavy Ion Collider (RHIC) might unlock some of the secrets of matter at high densities that are so important to understanding the early universe.

The only downside to this trip is that I suspect that my Internet access will be very sparse over the next three days, and so I don't expect to blog again before Friday, although I will if I can. When I get back I'll give a more detailed report on the conference.

Ian McEwan on the Impact of the London Bombings

2005-07-10T21:40:00.000-04:00

As I've mentioned a number of times before, Ian McEwan is one of my favorite authors. I have enjoyed essentially everything I've read that he has written. The Guardian is carrying a small article that McEwan has written about the impact of the London bombings on everyday life in the capital. It would be pointless for me to try to describe his writing in my clumsy way here, but I think it's worth a read.

Café Scientifique Syracuse - a Teaser

2005-07-10T14:44:00.000-04:00

I was intending to write a long post today about the upcoming inaugural meeting of Café Scientifique in Syracuse. This required me to finish the web site and use a number of files that are stored on the Physics department server. Unfortunately, I had forgotten that this server is down for almost the entire day while the switch to a new server is completed. I do still want to write something about this, in order to get the message out to anyone in Syracuse who may be interested and happens to watch this space, so I'm going to give the bare bones here, and then provide a lengthy discussion of it in a longer post very soon.

As explained on the Café Scientifique web site,

"Cafe Scientifique is a place where, for the price of a cup of coffee or a glass of wine, anyone can come to explore the latest ideas in science and technology. Meetings have taken place in cafes, bars, restaurants and even theatres, but always outside a traditional academic context.

The first Cafes Scientifiques were held in the UK in Leeds in 1998. Since then, Cafes Scientifiques have sprung up in Newcastle, Nottingham and Oxford and the network has now begun to expand to other cities in the UK. We hope that by 2003 there will be a thriving network of 20 to 30 Cafes that meet regularly to hear scientists or writers on science talk about their work and discuss it with diverse audiences.

Cafe Scientifique is a forum for debating science issues, not a shop window for science. We are committed to promoting public engagement with science and to making science accountable."

The idea has now spread to a number of different places worldwide. The Syracuse branch is being organized by a group of us spanning the science departments at Syracuse University - myself (representing Physics), Ana de Bettencourt-Dias (Chemistry), Scott Samson (Earth Sciences), Paul Verhaeghen (Psychology) and a Biologist to be named very soon.

Our inaugural meeting will be held at Ambrosia restaurant in Armory Square in Syracuse on August 2nd at 7pm. There will be a $5 door charge, but this will cover some delicious snacks provided by Ambrosia, and our own bartender so that we don't constantly have to go into the main part of the restaurant to order drinks. For the first meeting, we will cover the door charge for the first thirty people who arrive.

When I write my long post about this I'll include links to our web site, the title and speaker and directions to Ambrosia, but, given my technological restrictions, I've written all I can for now.

A Trotskyite Takes on Terror

2005-07-07T19:41:00.000-04:00

I have spent most of today flipping between news sites and listening to the audio feed of the BBC news on my computer while trying to get a little work done. Needless to say, the latter effort was not particularly successful. It has been immensely saddening to watch the carnage in London, but at the same time it has been heartening to watch Londoners' remarkable response to this tragedy.

Today is not, of course, the first time London has faced bombs, and not even the first time it has faced terrorist ones. Nevertheless, in the midst of what must have been a terrifying situation, I thought people did as well as one could imagine.

Almost everyone who is anyone, and plenty more who are not (case in point right here) have had their say on television, radio and in the print media. Some responses have been touching and eloquent (actually the least eloquent I heard was from Donald Rumsfeld, one of the few native "English" speakers commenting) but the one that stood out for me was by Ken Livingstone, the Mayor of London.

Livingstone is the kind of guy who could never win office in the U.S.. I could go into a number of reasons, but it is probably enough to say that he is a self-described Trotskyite (Red Ken, as I recall him being called). I've sometimes found him to be a thoughtful and caring person and sometimes heard him say things with which I wholeheartedly disagree. However, his somewhat emotional response to today's events was nicely done. He said

"This was not a terrorist attack against the mighty and the powerful. It was not aimed at presidents or prime ministers. It was aimed at ordinary, working-class Londoners, black and white, Muslim and Christian, Hindu and Jew, young and old.

It was an indiscriminate attempt to slaughter, irrespective of any considerations for age, for class, for religion, or whatever.

That isn't an ideology, it isn't even a perverted faith - it is just an indiscriminate attempt at mass murder and we know what the objective is. They seek to divide Londoners. They seek to turn Londoners against each other."

This is a comment that certainly resonates with me. Livingstone's entire statement is somewhat longer, ending with

"Finally, I wish to speak directly to those who came to London today to take life.

I know that you personally do not fear giving up your own life in order to take others - that is why you are so dangerous. But I know you fear that you may fail in your long-term objective to destroy our free society and I can show you why you will fail.

In the days that follow look at our airports, look at our sea ports and look at our railway stations and, even after your cowardly attack, you will see that people from the rest of Britain, people from around the world will arrive in London to become Londoners and to fulfill their dreams and achieve their potential.

They choose to come to London, as so many have come before because they come to be free, they come to live the life they choose, they come to be able to be themselves. They flee you because you tell them how they should live. They don't want that and nothing you do, however many of us you kill, will stop that flight to our city where freedom is strong and where people can live in harmony with one another. Whatever you do, however many you kill, you will fail."

This is a little more simplistic but I can recognize its power nevertheless, and I'm glad Livingstone is saying things that generally make sense. Complex as the issues surrounding terrorism are, and as angry as I am with some of the nonsensical things we have done, such as the war in Iraq, in the name of the war on terror, I have found myself despairing over some of the silly comments made by people with whom I share many other views.

A case in point is Ward Churchill, who became infamous for his comments about the victims of the September 11th attack on the World Trade Center. I support Churchill's right to free speech and his academic freedom. His comments just made me sit and shake my head. I'd like to hear what he has to say about the London attacks, on people using public transportation to get to their varied jobs around the city. Somehow, after Livingstone's inspired comments, I think Churchill will be hard pushed to refer to these victims as "Little Eichmanns" or as the British equivalent of the "technocratic corps at the very heart of America's global financial empire."

An Attack on London

2005-07-07T07:16:00.000-04:00

I have just woken up to the news of the coordinated bombs on the transport system in London. It's hard to say anything meaningful at this point, except the obvious - that one feels both saddened and angered to see such an appalling event. I've just sent out emails to family, friends and colleagues in London, to see if they are all safe, and I am now waiting for responses.

You can be sure I'll post more heavily about this in the coming days. For now, I'm hoping that the British response will be to identify who is responsible and then to do everything possible to apprehend or kill them. I'm also hoping that such an effort won't become diluted by an obsession with regimes in countries unconnected to these attacks. I don't make this as a flippant comment on Iraq; I just don't want my government to make the same mistake again.

Machine vs. Man

2005-07-06T22:57:00.000-04:00

Time for blogging is a little short this week, for reasons I'll explain in the near future. I did want to point out an interesting article in The Christian Science Monitor though. There is quite broad agreement among scientists that scientific goals are far more easily, safely and cheaply attained through the use of robotic space missions, rather than manned missions. The CSM article discusses this from a variety of viewpoints. For my tastes, I liked the following quotes from James Van Allen, professor emeritus at the University of Iowa.

""I'm one of the most durable advocates for space exploration around," But beyond Apollo's moon landings and missions to service the Hubble Space Telescope, he adds, human spaceflight hasn't contributed as much to humanity's understanding of the cosmos as increasingly sophisticated unmanned probes.

"It's the cost," he says. "If it was easy to do, I'd be all for it." But with record federal deficits, an increasingly expensive war in Iraq, problems with Social Security, and other demands on the federal purse, the benefits to science from human spaceflight over the past 10 to 15 years have not justified the cost.""

The British Response to July 4th

2005-07-04T23:56:00.000-04:00

While Americans everywhere were celebrating victory over my countrymen, The Guardian is reporting that, after waiting patiently for 229 years, a crack team of British special force troops has struck back. These brave souls have succeeded in penetrating White House security and retrieving Tony Blair's balls from the crystal display case in the Oval Office, in which they have been on prominent display for the last four years.

At least, this is the only explanation I can think of for an article titled "Blair May Snub U.S. on Climate",

Celebrating Our Ignorance

2005-07-02T09:30:00.000-04:00

The new issue of Science celebrates that magazine's 125th anniversary by exploring 125 major open scientific questions. I haven't had time for a thorough read yet, although I'm looking forward to it, but a couple of things have already caught my eye.

The subtitle of the Science issue is "What Don't We Know?", and this is one reason to be excited about the contents. For me, one of the great powers of the scientific approach to the world lies in the ability to say I don't know. This simple statement of ignorance drives scientists along, spurs new discoveries, keeps us awake at nights and, despite what those who do not understand science might say, firmly distinguishes science from any of the belief systems with which it is sometimes compared. New discoveries in science are triumphs for those directly involved, for science in general, and for humankind as a whole. They are rightly heralded by scientists, journalists and the public alike. But visit the office or laboratory of any practicing scientist the day after a major new discovery is announced, and you'll invariably see them sitting around asking "How does this cast light on other unanswered questions?", "How can this help us with other things we don't know?", "What next?!". It's all about moving on - we're excited by what we don't know.

Because of our sceptical attitude, and willingness to say what we don't know, there is a sense in which scientists know less than many other people in our society. I'm using "know" here in the sense that if someone truly believes they understand the answer to a question, independently of the actual evidence that that answer is correct, they truly think they "know" something. It is true that scientists know many fascinating, sometimes technical, sometimes arcane facts about nature. However, the broad strokes of many of these ideas are often also widely accepted by society. However, in addition to this knowledge, many members of society think they know vast "truths" about the universe beyond those established by rational enquiry. Because scientists are typically unwilling to sign on to such unwarranted beliefs, we often "know" less than others. Despite being frequently derided as "arrogant know-it-alls" (which we sometimes ask for), I think there's a reasonable case to be made that scientists are "humble know-nothings" (but I'm guessing people won't be clamoring to adopt this interpretation).

I've written before about the crucial role played by science journalism in our society. At its best, great science writing doesn't just provide a jargon-free, simplified, analogy-laden version of what scientists write in their technical journal articles. Rather, it helps frame the crucial issues, shows how they fit into the wider realm of scientific and human enquiry and, perhaps most crucially, conveys a picture of how science works, including the power of acknowledging the things we don't know.

I was therefore delighted to see that the Science issue contains an opening essay by one of my favorite science journalists, Tom Siegfried, titled "In Praise of Hard Questions". This is an extremely well written article, which I think presents science in an exciting and beautiful light. In a paragraph that partially quotes David Gross, one of the 2004 Nobel Prize winners in physics, Siegfried writes

"Science's greatest advances occur on the frontiers, at the interface between ignorance and knowledge, where the most profound questions are posed. There's no better way to assess the current condition of science than listing the questions that science cannot answer. "Science," Gross declares, "is shaped by ignorance.""

Science is not the study of a dead body of knowledge. The action is at the frontier and there are mountains of interesting questions and fascinating work to be done. One thing that Siegfried's essay accomplishes is to demolish the silly argument that some commentators have made - that we are approaching the end of science. It seems to me that we now realize that there is more science left to do than we ever realized before, and I hope that young people reading Siegfried's article and this Science issue can see that there's a place for them in the great endeavor. It would provide a fascinating focus for a class discussion led by an innovative science teacher.

There is a Heaven After All

2005-06-30T18:40:00.000-04:00

Anyone who regularly reads Orange Quark knows that I spend a fair amount of time outraged over the increasing encroachment of religion on the rational world. It's not because I'm a glass-half empty sort of guy, or that I love complaining (although it is true that neither of these help); it's just that it's amazingly rare that I see anything in the news these days to give me hope that reason will ultimately prevail. When something encouraging finally does come along, I can be all sweetness and light, honestly.

The New York Times has a wonderful, happy, feel-good story about a very special summer camp for kids. This delightful place is called Camp Quest and is in, of all places, southern Ohio. And what is it that makes me giddy for Camp Quest? As the Times reports

"Providing a haven for the children of nonbelievers is what Camp Quest is all about. As the camp's official T-shirt announces, it's a place that's "beyond belief." More precisely, it claims to be the first summer sleep-away camp in the country for atheist, agnostic and secular humanist children."

Isn't this great? I'd love it if this were all they did - just provide a place where kids aren't made to feel odd because they don't subscribe to others' fantasies - but it gets better. The camp sees it as part of its mission to celebrate and teach reason and rationality. For example

"At the opening campfire ceremony, Mr. Kagin issued a set of challenges for campers to respond to in skits on the final night of camp. One such challenge: Help residents of the faraway planet Questerion understand how life on earth came into being. Another challenge: Prove that the two invisible unicorns in residence do not exist.

As in years past, camp leaders also worked on presentations in science and other natural (as opposed to supernatural) phenomena. This year's subjects were raptors and meteorology, including a demonstration of a portable weather station. Also, Gene Kritsky, a biology professor at the nearby College of Mount St. Joseph, talked to campers about creationism, arguing that the theories used to try to disprove evolution fail to hold up."

I'm not going to rant about the pressures faced by nonbelievers in this country - it'd ruin my happy happy post. I'm just going to end with the words of Edwin Kagin, the camp's director and one of its founders

"We're serving as a night light in a dark and scary room"

Imagine me with a big goofy smile across my face.

It's 8pm - Do You Know Where (Your Brain Thinks) Your Penis Is?

2005-06-28T20:00:00.000-04:00

You just have to read this short article from New Scientist. It sounds like an unusual, but interesting piece of science. What made me laugh though is the description if the experiments themselves:

"Christian Kell at the University of Frankfurt in Germany has put eight men into an MRI scanner to help settle the question. Using a soft brush, Kell stroked parts of each volunteer's body while recording brain activity."

We need research like this in the U.S., because if the religious right got wind of federal funding for a guy sitting in a laboratory stroking other guys' penises with a soft brush, it's just possible that it would draw the totality of their fire and the rest of the scientific establishment could relax for a while.

Tell Joe Barton How You Feel

2005-06-27T20:39:00.000-04:00

At the risk of being pedantic (Oh, who am I kidding, I'm going to go on and on about this stuff until it stops), the attack on science in the U.S. is going ahead full steam. Congressman Joe Barton (Republican, of Texas), chairman of the House Energy and Commerce Committee, is sending intimidating letters to the members of the Intergovernmental Panel on Climate Change and to Arden Bement, Director of the National Science Foundation. It's true - take a look! Chris Mooney has some excerpts from the letters, so I won't reproduce them here, but will just comment that they are of a kind designed to make scientists think twice about undertaking research on such a politically sensitive topic as global warming.

Representative Barton's tactics are just part of the more wide-ranging assault on scientific evidence that the Bush administration is waging. I'm not going to go through them all again, but I'm not going to stand by either. The congressman has a web site through which you can send him a message, but it won't accept your comments if you're not from his district. However, you can send a message to the House Energy and Commerce Committee, telling them what you think of Barton's tactics, and I'm going to use it right now.

I just sent a message with the following content:

Dear Congressman Barton,

I have recently become aware of the letters you have sent to the members of the Intergovernmental Panel on Climate Change and to the Director of the National Science Foundation. As a scientist myself, I am extremely concerned by the tone and implications of these letters and consider them a thinly-veiled attempt to intimidate honest scientists into avoiding work that might lead to an opinion different from the current administration on topics that are politically sensitive.

I strongly encourage you to desist from sending letters of this kind in the future and to leave reputable scientists alone to pursue their research, regardless of the political import of its outcome. By attempting to cast unreasonable doubt on solid scientific evidence you are doing your constituents and the rest of the country an immense disservice.

Sincerely,

Dr. Mark Trodden

If we all, scientists and non-scientists, don't fight back against these outrages, we can hardly complain as science is eroded in this country. I would strongly encourage you to send your own email, or even a version of mine, to the Congressman, via the link above. It'll only take a minute and will let him know that there are lots of people out there that don't think it's fine to treat scientists in this way. Please take a moment to do it. If you want to drop me a comment here telling me you did it, all the better; but in any case, please do it!

I'm Back, and Random Tenning

2005-06-24T14:49:00.000-04:00

Early this morning I drove back to Syracuse from the Perimeter Institute. I had a wonderful few days there, enjoyed giving my lectures and seeing old friends, and spent quite a lot of time talking to students after my talks. Great fun! In addition, I got to hang out in Perimeter's cool, modern building, which I found to be both beautiful and extremely relaxing - I'll have to go back.

Since I need to deal with all kinds of backlogged issues here, and it just so happens to be Friday, I'm going to take the Friday Random Ten cop-out for the rest of this post. More tomorrow

1. Moby, Find My Baby.
2. The Jam, The Modern World.
3. The Beastie Boys, Tough Guy.
4. Lauryn Hill, Miseducation of Lauryn Hill.
5. Elvis Costello, Oliver's Army.
6. Miles Davis, Dear Old Stockholm.
7. Blondie, One Way or Another.
8. Anthony Hamilton, Comin' From Where I'm From.
9. Hot Chocolate, You Sexy Thing.
10. The Cranberries, The Rebels.

In the Land of the Almost Dead, the Not Yet Alive Reign

2005-06-22T16:47:00.000-04:00

Here brother Bush goes again, trying to impose his religious "morality " (or at least that of the people who he'll need on his side for a presidential bid) on people. Just as with his persecution of Michael Schiavo, he's now coming out against stem cell research. Well there's a shocker. Apparently the Governor claims that no universities in Florida will perform embryonic stem cell research. Kind of ironic that this should happen in a state so disproportionately populated by those in desperate need of what this research promises.

Keep picking the crazy side of issues Jeb. Help us out. We don't need another of you in the White House hurting America.

ACLU Weighs in on the Attack on Science

2005-06-22T07:41:00.000-04:00

The Washington Post is carrying an article on an American Civil Liberties Union (ACLU) report stating that

"The Bush administration's response to the Sept. 11, 2001, terrorist attacks has dangerously undermined U.S. scientific enterprise and national security by abridging the constitutional and academic freedoms that have long fostered the nation's technical superiority"

In my opinion this is clearly true. The most obvious damage can be seen in the drop in the number of foreign applicants for U.S. Ph.D. positions. On multiple occasions I have had colleagues from Europe and Canada tell me that there is, in fact, one thing they have President Bush to thank for, and that is the increase in quality foreign Ph.D. students they have seen over the last few years.

However, I actually think that the response to 9/11 is not the primary problem with the current administration's attitude to science. As I've mentioned before (a number of times), the main problem is with the willingness to twist, modify, ignore, politically manipulate and outright lie about any scientific results or approaches that conflict with the religious or corporate interests that have a stranglehold on our nation.

This attitude is harming progress on preventing teen pregnancies and sexually transmitted diseases; is a threat to women's health; is preventing us from aggressively addressing the causes behind climate change; is clouding public understanding of established scientific theories such as evolution and threatens to undermine the technological and scientific base crucial to a vital future for our country.

Dinner with Friends

2005-06-21T22:47:00.000-04:00

I just got back from a delightful evening - dinner and drinks with Don Marolf and Cliff Johnson (aka cvj). These guys are also lecturing at the Perimeter Institute summer school that I mentioned yesterday. Now I have to make sure I know what I'm going to talk about tomorrow and try to get a good night's sleep. So any hopes I might have had of posting anything profound here will not be realized.

Perhaps I can try to hold some people's attention by pointing them to the sad story of the solar sail. Let's keep our fingers crossed that a signal from the spacecraft is received over the next couple of days.

Strings, Gravity and Cosmology at the Perimeter Institute

2005-06-21T00:01:00.000-04:00

Tomorrow afternoon I'm heading off to the Perimeter Institute (PI) to deliver a couple of lectures on cosmology at their Summer School on Strings, Gravity and Cosmology. The Perimeter Institute is an interesting place - a collection of theoretical physicists, working on foundational issues in a variety of different areas, from a variety of different directions. The facility was founded by Mike Lazaridis of Research in Motion (RIM) - the people who brought you the Blackberry handheld - and is funded from private donations by Lazaridis and two other RIM executives. This alone makes PI rather unusual.

The summer school should be fun, although I can only stay for a couple of days and will unfortunately miss what is sure to be a tremendous public lecture about string theory on Friday by Rob Myers. As well as giving a couple of talks, I'll also get to see some physicist friends (one of whom occasionally comments on my blog using the name "cvj") and see Perimeter's fancy new building. All of this will leave me with very little time for blogging, so I might be a little scarce for the next two days (I'll try though).

Real Journalism

2005-06-20T23:34:00.000-04:00

From the Guardian, excerpts from the reports of George Weller, the first western reporter to reach Nagasaki after the atomic bomb was dropped. I don't have insightful comments. It just makes for fascinating and rather sobering reading, and must have been extremely difficult work. Of course it's nothing compared to having to chase Tom Cruise and Katie Holmes around, but life was easier back then.

How Low Can You Go?

2005-06-18T00:20:00.000-04:00

Not content to have put Michael Schiavo through hell while he had already had to suffer for years caring for his brain-dead wife, Governor Jeb Bush is doing his best to make sure that Schiavo cannot pick up the pieces of his life now that Terri Schiavo's body is finally dead.

Because the recently released autopsy report showed results entirely consistent with the assertions made by the doctors who had examined her (but inconsistent with the claims of the doctor who is the Senate majority leader, and who didn't examine her), the Terri Schiavo case has turned into an even larger political mess for those who tried to use it as a cheap way to further their political ends. No matter though, the New York Times is reporting that Jeb Bush is now seeking an investigation into Michael Schiavo's actions on the night, back in 1990, that his wife collapsed.

This really is outrageous. What's the idea here? If Bush can make Michael Schiavo look like a callous, uncaring husband, who deliberately contributed to his wife's condition, is that supposed to draw attention away from the fact that Republicans violated this family's privacy in order to appease their rabid religious right supporters? I'm hoping that Americans are smart enough not to be fooled by such absurd tactics. Most Americans certainly saw through the original scheme, and the President's approval rating has taken a hit as a consequence. I'm hoping that his brother's is similarly affected - it might help us to avoid a third Bush disaster in the White House.

Blogging from Iraq

2005-06-17T16:15:00.000-04:00

As I've mentioned before, my friend Teri Weaver is spending a couple of months in Iraq as part of her job as a journalist for Stars and Stripes. Teri has been in Iraq since late May and has posted a series of impressively written accounts of her time there on her blog. The most recent, posted just today, discusses, among other things, what happens when U.S. troops have to go to pay out money to the family of someone killed in crossfire.

Teri's writing provides fascinating and sometimes upsetting insight into day-to-day life in Iraq. Take a look.

The Fathers of Modern British Cosmology

2005-06-16T21:15:00.000-04:00

The Guardian has an article discussing a couple of new books concerned with the scientific legacy of Fred Hoyle, the remarkable British cosmologist who coined, albeit sneeringly, the phrase "the Big Bang". Hoyle was one of the people who founded modern cosmology in Britain, and his influence and research were behind the work of many of the great minds working there.

Hoyle is perhaps best known for the steady state theory of the universe, a serious model of an unchanging universe that ultimately was ruled out by the increasingly accurate observations that lent ever-stronger support to the Big Bang model. Hoyle developed the steady state theory in collaboration with Thomas Gold and Hermann Bondi. I never met Hoyle or Gold, but have had the privilege to meet Hermann Bondi on many occasions, although none of them recently. Bondi was the Master of my college, Churchill College, when I was a mathematics undergraduate at Cambridge University. In fact, I had seen him give a talk on humanism a couple of years before I went to university and been incredibly impressed with him even then. (I once sat next to Bondi's wife, Christine, an intellectual powerhouse in her own right, at a college dinner and she was also delightful, even going so far as to help me get a summer research job.)

What impressed me about Bondi is the same thing that impresses me about Hoyle when reading the accounts of his life. These guys were giants in their field, the same field in which I work now, but beyond that have been major intellectual forces beyond the confines of their research discipline. It is my impression (although I have no data and would be interested to hear what others think) that such widespread intellectual engagement is rarer in recent generations of physicists. I don't think the people are less smart or less able, I just feel that there are relatively fewer of them with such broad interests.

The Guardian article lists many of the areas in which Hoyle made contributions, but points out, in terms that I don't think one would see is a U.S. newspaper, that Hoyle was all these things

"and - in later life - a grade one batty boffin who argued that diseases were forged in space and delivered to Earth by comets and that the archaeopteryx specimen in London's Natural History Museum was a fake."

Well, you can't have it all. If I could have the impact of a Hoyle or a Bondi I'd be over the moon, and you could call me a batty boffin as much as you liked.

Assuage That Gaming Guilt

2005-06-14T20:13:00.000-04:00

When I was in high school, my friends and I would often spend Saturday afternoons playing pool and video games in a downtown arcade in my home town (OK, we would also spend part of that time in several pubs that didn't seem to care how old we were, but that's not important right now). I enjoyed some of the more challenging video games, and was quite good at them, but I was in no way what you'd call an addict.

Fast forward to graduate school. One of my friends owned a home video game console, and none of the games interested me at all, until the now-famous Doom came along. For reasons that aren't clear to me, we spent inordinate amounts of time on that game, working through the many levels until we finally finished it. After that, I was once again uninterested in any games that my friend bought.

Fast forward another ten years, to this past week's vacation, to which that same friend brought his Xbox with, wait for it, the newest incarnation of Doom - Doom3. You guessed it - I became hooked again, and each day we spent a couple of hours working through the game. Once again I can't really say why it grabbed me, but it was wonderful escapist fun.

Now; the above admission goes against the unspoken academic code, which one might paraphrase as

"Do not engage in any activity that is part of popular culture. Such activities include, but are not limited to; playing video games, playing card games (bridge excepted), watching movies without a serious social message and watching television (PBS, in particular NOVA, occasionally excepted). Any violation of the above may lead to a stubborn stain on your intellectual reputation, which may only be removed by repeatedly attending highly experimental theater."

It is hard to articulate the amount of guilt academics suffer when they have violated this rule, especially if they've done so deliberately. But once one realizes that such guilt exists, it helps one to understand comments like

"Last night I was looking for the NOVA program on Flying Casanovas (the Bowerbird really is fascinating you know) when I accidentally turned NBC on and caught the beginning of some crime show. I think it might be called `Law and Order', but I'm not sure. Anyway, I was too lazy to change channels and ended up watching the whole thing. It was kind of fun actually, in a predictable, corporate way."

Well, before all you fellow academics out there jump all over me, I should say that I'm exaggerating a bit here. But every one of you knows what I mean.

Given all this, an article on wired.com allows those of us who have violated the video game clause to assuage our guilt somewhat. This article points out that the next generation of home video game machines would be perfect for a distributed computing project such as LIGO@home (searching for gravitational waves), SETI@home (searching for E.T.) or Folding@home (searching for the solution to protein folding), which already take advantage of down time on personal computers. These are raw data-crunching projects, for which the sheer computing power of huge numbers of machines is extremely useful. As wired.com puts it

"Distributed, or `grid,' computing breaks down complex computing problems into small steps that can be solved in parallel by thousands or even millions of machines at once. It is basically the difference between hiring someone to label 1,000 envelopes for you and asking your friends to each label 100 when they get the chance. In this example, the hired person is the traditional mainframe crunching numbers, while your friends are personal computers all over the world that offer to crunch small packages of calculations when they're not busy."

The article ends with the thought

"So, let my console fold proteins or search for E.T. when I'm not using it. Let the public take a larger role in innovative research efforts. Most importantly, let me be able to end any console debate with, `So what if your system lets you watch movies and TV, listen to music and play games? My system cures cancer.' "

This seems like a wonderful idea to me. Huge numbers of kids (OK, adults as well) own video consoles and think of the time that these machines spend idle while the kids are, for example, at school. In fact, with a little thought, one might be able to use this aspect of the consoles to inform kids about some interesting science. If one was to take this really too far, one might imagine marketing campaigns designed to pitch different distributed computing projects to gamers. Oh dear, there I go again, offending the wrong people.

Most importantly, the next time I take a vacation I'll also be able to say "Sure, I didn't personally do any physics while I was away, but the time that I spent on the beach and not blowing away Cacodemons with my BFG-9000, I was playing a crucial role in the LIGO data analysis project"

The Gravitational Lens, Issue 2

2005-06-14T14:15:00.000-04:00

The second issue of The Gravitational Lens is now out. I helped out a little with the writing of this one. There are brief discussions of testing General Relativity with double pulsars, of gravitational radiation from strangely shaped pulsars and of primordial inflation and the accelerating universe. Enjoy.

I'm Back

2005-06-13T14:55:00.000-04:00

I just got back from vacation and am realizing that I have a lot of blogs to read and a lot of writing to get down to. I'm going to do both as soon as I unpack.

Vacation was great. We were in Corolla, on the Outer Banks of North Carolina and I had absolutely no internet access all week. The weather was beautiful, I was surrounded by most of my closest friends and we indulged ourselves like the hedonists we all are.

Sara and I spent last night in Philadelphia so that we could eat at one of my all-time favorite restaurants - Alma de Cuba - and drove back the rest of the way this morning.

OK; unpacking, then some blogging.

Vacation!

2005-06-03T23:18:00.000-04:00

Tomorrow morning I leave for a week's vacation in North Carolina. Sara and I are joining ten friends in a great beach-house. I plan to read a lot, play volleyball, spend plenty of time in the ocean, drink lots of cocktails and do no physics at all. We academics don't take vacations often, so I'm really looking forward to this.

Since I still feel too new to blogging to pass things over to a guest blogger, I'm probably not going to post for the next nine days. I hope to make up for it when I get back. Next time I'm away for an extended period (China for two weeks in August) I think I'll try the guest blogger idea. I have plenty of good candidates in mind.

More Cosmic Connections

2005-06-02T23:20:00.000-04:00

If you're a regular reader of Orange Quark, you'll have seen not just one, but two previous posts about the Cosmic Connections exhibit at the Milton J. Rubenstein Museum of Science and Technology (MoST) in Syracuse. I promised that I'd post some photos of the opening when I finally got them, and they arrived today. Although I'm just showing a small selection here, I'm sure we'll have a larger choice on a web page some time soon.

This first one shows the original model of the exhibit, designed in collaboration (OK, they did most of the pretty stuff) with a class of students from the design program here at Syracuse.

This one shows the entrance to Stage I, which is the part we've just completed. You can just make out the side of our stunning laser-blasted sculpture of the galaxy. I don't have a great picture of this, but when I get one I'll definitely post it - it's well worth seeing.

Here's a picture of a random selection of members of our team, with Syracuse's new Chancellor, Nancy Cantor, second from left, and the director of the MoST.

Here, I'm explaining to the Chancellor the role that dark matter plays in structure formation. Behind her you see our hologram of an N-body simulation of large-scale structure. It really is a beautiful thing. Reflected in the hologram, you can see Sam Sampere, one of the people who worked long and hard to make this exhibit work.

We had a great time at the opening and, despite our excessive worrying beforehand; it seemed to be a real success. Now we need to roll up our sleeves and get stuck into Stage II.

Computing and the Cosmos

2005-06-01T23:12:00.000-04:00

The BBC is carrying a nice little story about the "Millenium Run", a supercomputer simulation of cosmological structure formation, in which the dynamics of 10 billion dark matter particles were tracked over 13 billion years of cosmological evolution. Numerical simulations are a crucial part of modern cosmology, allowing us (where by "us" I mean people like me, but who know how to write huge, complicated N-body codes) to understand how well-defined interaction rules between dark matter particles, acting in an expanding cosmos, lead to the wonderfully rich, complex, and structured universe we see today.

Without the use of computers there are many ways to understand, in broad terms, how structure formation takes place. However, in order to make detailed comparisons between theory and observations, hard-core computational cosmology is a must. You might wonder why the simulation just tracks dark matter, but it turns out that dark matter is the crucial part of why clusters of galaxies form in the patterns they do. There is a lot more dark matter than regular matter (the stuff that glows). This dark matter gathers together under the effects of gravity, creating large conglomerations, the attraction towards which causes the regular matter to clump up into the clusters of galaxies we see today. It's a beautiful story, and one that is borne out wonderfully by the comparisons between the Millenium Run simulations and the data from the Sloan Digital Sky Survey.

Carlos Frenk, who is one of the world's leaders in this area, is quoted in the BBC story, saying

"We have learned more about the Universe in the last 10 or 20 years than in the whole of human civilisation"

This is a big bold claim, but I think it is entirely fair. The tremendous progress in cosmology in the last couple of decades has given us a coherent picture of the universe; more detailed than many cosmologists had thought would ever be possible. This data is going to continue to flood in over the next few decades, further focusing attention on the fascinating question of how the observed cosmos connects to our theories of fundamental physics. It's a daunting task, but oh so much fun to be faced with.

The Assault on Morality Continues

2005-05-30T21:29:00.000-04:00

Well, he's out of the gate. The freshly minted Pope is weighing in on Italian politics. Benedict XVI is supporting a boycott of a referendum on medically assisted fertility. The referendum is designed to get rid of absurd restrictions on the current fertility law, which "bans donations of sperm and eggs; defines life as beginning at conception; and allows fertility treatment only to "stable heterosexual couples" who are living together and can prove infertility."

I don't suppose we can expect anything else from a Pope, but we shouldn't lose sight of what a terrible assault on morality this boycott represents. All these possibilities - the donation of sperm and eggs, allowing a woman the right to choose and fertility treatment for unmarried couples, including homosexual ones - are wonderful, kind, and caring. They are designed to improve the quality of life for countless human beings. While people may disagree on whether life begins at conception, I don't think there's anything controversial about the fact that life does not end at birth.

What could be more moral than a society that devotes itself to improving the quality of life for all its members? What kind of organization devotes itself to trying to influence the political system to marginalize some members of society?

Lest one think that the church is merely preaching to its members, and not actively interfering in the political process, consider this quote from the Pope's recent letter to Spanish bishops

"the transmission of the faith and religious practices cannot remain confined to the purely private sphere."

Look around you. Look at your friends. Look at the gay ones, the unmarried ones, the single ones and the infertile ones, and think what this type of statement says about them, about their status on this planet. Doesn't it make your blood boil? It should. How do we put up with such bigotry, just because it comes clothed in the garb of religion?

If you think of yourself as a moral person, this type of attitude should appall you.

Of course, it's not just in Italy that such thinking threatens the moral fabric of society. The far right assault on morality here in the U.S. has gained quite some momentum under the patronage of the Bush administration and its support of dogma. I thought we were assured life, liberty and the pursuit of happiness. How is that consistent with denying that to part of the population when their pursuing it harms no one?

Your Parents May Have Been Right!

2005-05-27T18:26:00.000-04:00

I'm referring to this story, about reports of partial vision loss among some men taking either Viagra or Cialis. The question I have is; I thought you were only supposed to go blind if you were the only person in the room.

Maybe it's a pharmaceutical manifestation of our current moral revolution. All sex is wrong these days.

Why Aren't I Asleep Yet?

2005-05-27T02:29:00.000-04:00

Well, when I last posted I was in my hotel room working and expecting to go to bed afterwards. However, a surprising thing happened, and one for which I have the blog and email to thank.

It turns out that my good friend JoAnne Hewett (the one from my "Wine Snobs Rock" post early on in my blogging) was also at Fermilab today, serving on a HEPAP (High Energy Physics Advisory Panel) sub-panel. Neither of us would have known that the other was around except that JoAnne read my blog when she got back to her hotel room tonight and found out I was in town. She emailed me and, although it was late, we decided it was ridiculous not to get together, especially since our hotels are just two blocks apart.

I just got back, after we closed down the Warrenville Rock Bottom Brewery. It was great to spend this spontaneous time with JoAnne, and it just wouldn't have been possible without the web and email. It is entirely another, sadder fact that we're both now back on our computers working (I know, because we just emailed each other). Oh well, you can't fight a physicist's true nature.

I See Physicist Bloggers

2005-05-26T22:11:00.000-04:00

Today was a big day for bumping into physicist-bloggers. This afternoon I dropped by the Fermilab Theoretical Astrophysics group and saw this guy, although he was on the phone, so I didn't drop in. This evening I went to a nice Indian restaurant and ran into this guy, who has written on his blog about the escapades of this guy, who was one of my dinner companions. And, as I've mentioned, tomorrow I'm going to see this guy.

I see physicist bloggers. They're everywhere. They think they're regular physicists but they're not; they're bloggers.

Bugs, Blair and Balls

2005-05-26T08:05:00.000-04:00

In Britain there is something of a fuss over MMR (Measles, Mumps, Rubella) vaccinations, with the uptake rate now perhaps as low as 72%. When I was a child, to the best of my understanding, basically everyone had the MMR vaccination - it was just a completely normal thing. Now, however, Britain risks measles and mumps epidemics because significant numbers of parents are refusing to have their babies vaccinated.

The reason for this appears to be the existence of a couple of "studies", linking the MMR vaccine in one case to Crohn's disease, and in another to autism. The results of the first (and quite old) study have since been ruled out by later, better research, and the second study was, well, shoddy. The Fins have since completed a very large and comprehensive piece of work that finds no such problems with the vaccine.

Nevertheless, people are stubborn and ill informed and (something about this sounds awfully familiar) large numbers of them are prepared to risk their children, and those of others, to serious diseases, because of this ignorance. It doesn't help that the leader of the nation (again, something is ringing a bell here) is one of those helping perpetuate the nonsense. Yes, that's right, Tony Blair has decided it's OK to expose his precious little cherub to these old-school infections. I guess we shouldn't be too surprised, given what Iraq has taught us about Tony's opinions regarding standards of evidence.

There is a short and funny piece about this by Ben Goldacre in the Bad Science section of today's Guardian. It's partly funny because I don't recall ever seeing someone use the word "balls" in a U.S. newspaper. Maybe it's because so few U.S. news sources have any. Here's a snippet (with apologies to my humanities-graduate friends (including my wife) who don't fall under this statement)

"Because, sadly, the natural world does not quite share my sense of retributive justice, nor does the paramyxovirus that causes mumps. If it were infecting only the innocent unvaccinated offspring of humanities graduates with no understanding of risk, I'd pretend to be sad on their behalf. But no. There were 8,104 cases of mumps confirmed in the UK last year, up from a combined total of 3,907 for all the previous five years, chart fans.

But mumps cases last year were predominantly in young adults, because young adults as a herd have the lowest immunity. And one in five young men who get mumps can expect orchitis, a new joy for fans of infected and inflamed testicles. If your balls hurt and you're infertile, you might wish to thank, for their peculiar interpretation and eulogising on the dangers of MMR: Andrew Wakefield, Nigella Lawson, Libby Purves, Suzanne Moore, Lynda Lee-Potter, The Daily Mail, Leo Blair's tight-lipped parents, and, let's be fair, every single national newspaper."

Makes you cross your legs just reading it.

Fermilab

2005-05-24T22:46:00.000-04:00

I don't think I'll find many opportunities for blogging over the next few days. I'm at Fermilab, serving on the U.S. Department of Energy site review team. It's a fascinating process, although our days are extremely full. Today we were in sessions from 8:30am until 6:45pm, followed by a dinner. We've been hearing about the collider, the particle physics experiments, experimental astrophysics and theoretical efforts in both areas. Tomorrow it's 8:30am - 8:00pm, and so I can't imagine too much blog-time developing. Nevertheless, service to the community is an important part of an academic's life, and so I'm not complaining about the workload.

I don't want to go into detail about the site review here - it's not the place. However, apart from the actual work involved, it is also nice to see some friends. I had dinner with, among others, Rocky Kolb and my collaborator Nemanja Kaloper, and hope to find a little time tomorrow for a quick beer with Joe Lykken. Over dinner we even found time to sneak some discussions about physics topics of common interest (yes, we're a wild bunch given half a chance).

The site review is over on Thursday afternoon, but I'm staying an extra day in the Chicago area to spend some time with Sean, doing some physics and, almost certainly, some fine dining. I'm always tempted to go back to the Frontera Grill, but there are so many new places to try that I'll probably end up doing that.

Anyway, I need to get some sleep. More when I find a little time.

Fun, Friends and Physics

2005-05-22T21:30:00.000-04:00

It's been a full weekend here in Syracuse. I managed to fit in a round of golf, a long cycle at Onondaga Lake Park, some time in the gym, dinner with friends, editing a draft of a paper and a delightful brunch.

For the last semester we have had a visitor in the department - Gianpiero Mangano, from Naples. Gianpiero is a particle physicist and cosmologist with extremely broad interests. It has been great to have him around and we have even managed to get a project going, which has led to the draft I was editing this weekend. Earlier today Gianpiero had me, my graduate student Antonio De Felice and his friend Akiko over for brunch. It turns out he is a tremendous cook and I left his place three hours later full of four wonderful courses and some nice wine.

One of the great things about being a physicist is that you get to know so many nice people from so many different parts of the world. Today we had two Italians, a Brit and a Japanese woman all having brunch. I don't get the impression that kind of gathering is too common in many other fields.

Anyway, I've had a lovely weekend and am incredibly tired now. Tomorrow afternoon I leave town to spend Tuesday through Thursday at Fermilab and then Friday visiting Sean in Chicago - a whole new mix of physics and fun. Hopefully I'll be able to find time to post at least a few times while on this trip.

A Torrent of CosmoParticle Data at the LHC

2005-05-21T22:29:00.000-04:00

There is an interesting article in this week's New Scientist, about the computing challenge posed by the absurdly large amounts of data that will be generated at the Large Hadron Collider (LHC). The LHC, which will turn on in 2007, will be the world's largest machine, colliding protons at extremely high energies and providing unparalleled insights into the fundamental nature of matter and it's interactions.

There are compelling theoretical reasons to think that our current theories of particle physics require modifying at precisely those energies that the LHC will probe. These current theories are the electroweak theory, which unifies electromagnetism with the weak nuclear force, and quantum chromodynamics (QCD), which describes the strong nuclear force. Because the LHC collides protons together, the particles that cascade out after the collision are the result of a host of electroweak and QCD interactions. The QCD part is particularly complicated, and figuring out which collisions are potentially interesting (a software task that particle experimentalists refer to as triggering) and should be recorded by computer, is a formidable task. The numbers - 15 million Gigabytes of data in year one alone - are truly staggering.

As the New Scientist article comments

"The torrent of information gushing forth from the LHC each year will be enough to fill a stack of CDs three times as high as Mount Everest. To make sense of it will require some 100,000 of today's most powerful PCs, so it is little wonder that CERN - the European centre for particle physics near Geneva that is building the collider - is co-opting a worldwide "grid" of computers to help store and analyse the data."

This computing task is one that it is easy for most physicists to forget about. Those of us not directly involved in the experiment tend to be focused only on the particle physics, and forget the massive engineering, design and computing effort required to make the machine work.

It's not just particle physicists who care about all this. Orange Quark readers will know my view, that particle physics and cosmology are now inseparable, and, indeed, I've commented before on the role that a future International Linear Collider might play in our understanding of the cosmos. The LHC is a necessary precursor to such an endeavor, potentially discovering the Higgs boson (explaining the origin of mass) and very possibly yielding evidence for supersymmetry, extra dimensions, or some other physics beyond the standard model. Any of these discoveries would have profound cosmological implications, perhaps for our understanding of dark matter and of the origin of the asymmetry between matter and antimatter (although the New Scientist article makes it sound a little too much like cosmology is the primary reason for building colliders).

But the list of people expectantly watching the LHC doesn't end with cosmologists. New Scientist quotes François Grey, an IT spokesman for CERN, and reports that

"CERN will need to ensure that no one team or institute hogs the grid. Physicists will probably barter computer time for now, but the system could later work on a pay-as-you-go basis. `Industry is very interested to see how we handle this,' says Grey. `A large grid could be very exciting for commercial business, but they need to know what the business model would be.' "

For me, a sufficient reason to build a machine like the LHC is the breathtaking possibility of understanding more about our universe at its smallest and its largest scales. However, it doesn't hurt that there are other sectors of society that see tangible benefits beyond the fundamental discoveries.

DashBlog

2005-05-19T15:40:00.000-04:00

Yesterday I installed the latest version of Mac OS X - Tiger - on my laptop. It's pretty slick in a number of ways, one of which is the "dashboard" feature, which gives one access to all kinds of little "widget" applications.

I found one called DashBlog that allows me to post directly to my blog from the dashboard, without having to go via blogger.com's site.

Well, I say it lets me do that. This is the first test. If it works, I may just do most of my quick posts from here.

The Phantom Menace

2005-05-18T06:54:00.000-04:00

The military, and the many corporations that feed, and are heartily fed by, it, must be rubbing their hands with glee (I've never been a fan of the term "military-industrial complex", thinking it sounds too Orwellian. But, under this administration, it may yet find its way into my vocabulary).

After the huge financial windfall (although a complete and utter scientific and technological farce) of President Reagan's Star Wars program, and its sequel: Star Wars II - National Missile Defense (developed under President Clinton and pushed forward under President Bush), comes the third piece of the trilogy, designed to continue the steady flow of tax dollars from serious social, educational and scientific goals and to your friendly neighborhood weapons companies.

The Phantom Menace to which I refer is the Air Force's recent push to move forward with the weaponization of space. "Phantom" seems an apt word here, given how transient and illusory the previous two initiatives have proved to be. "Menace" fits, because, as I said above, when the government proposes die-in-the-sky ideas like this one, the money has to come from somewhere. The price tag being thrown about for this is in the $100 billion range. Bear in mind that this is before the program gets going properly. How often has a program come in under budget?

We have an education system that is in desperate need of repair, with students leaving high-school ill prepared to compete in the very global marketplace that we have played such a key role in developing. We have no serious efforts to become energy independent - instead relying heavily on foreign oil, and hence ignoring a major way to improve our security. Poverty at home and abroad is being ignored. Scientific progress is being hampered, slowed and, in some cases, erased by harsh budgets and a twisting of the scientific process for the purposes of ideology. (Some of this happened as a direct result of the scientifically misguided moon-mars initiative. Some cynics even suggested that the real purpose of that idea was to funnel money to companies with military expertise. Now I might be starting to see their point.)

Addressing the real problems we face will make us happier, more competitive and safer. It will cost a lot of money, but the good news is that we can afford it, so long as we don't spend too much on our fantasy lives.

The Gift that Keeps on Giving

2005-05-17T20:40:00.000-04:00

I dropped the 'rents off at the airport this afternoon, and about now they should just have taken off from New York heading back to England. It was so great to have them here, and we'll miss them now that they've left.

I came home afterwards and was sitting reading, and realized that this simple pleasure is one of the things I have to thank my parents for. When I was a kid they were always reading. Every week we'd go down to the local library and pick up a whole new pile of books, take them home, read them, and be back again the following week to do it all again. They would lend me their library tickets to enable me to borrow more books than my limit. They would borrow books from the adult part of the library (not that adult section) when I wanted them, but wasn't physically old enough to have tickets for that part. They would only loosely police my room after I'd been told to put my light off and go to sleep after the end of the chapter. They would buy me books for my birthdays and for Christmases. And they would buy and borrow books to help me answer the annoying stream of questions with which I would harass them (When they visit, Sara and my parents bond over how annoying I can be, and this is one of their favorite traits to pick on).

In the neighborhood in which I grew up, I think it's fair to say that hardly any other parents encouraged their children to read in this way. My brother and I both grew up as readers; most other people I knew growing up didn't read then, and almost certainly don't today.

The parenting is so important, and I was so lucky! What a wonderful gift. I wish I knew how we could give this gift to children who are not fortunate enough to have parents like mine.

Taking the Blame

2005-05-16T23:21:00.000-04:00

Most news organizations, for example the New York Times, are reporting that Newsweek is withdrawing the article that mentioned that a copy of the Koran had been flushed down the toilet at Guantánamo Bay. At least 17 people died as a result of the violence that took place over this report. There has apparently been intense pressure from the White House on this matter, but the pertinent point is that the magazine can no longer sufficiently substantiate the story.

While it is right and proper for a story that cannot be adequately substantiated to be withdrawn, in my opinion almost all news stories on this are missing the most important point. While Newsweek may have done something wrong here, isn't it most ridiculous, most outrageous and most morally reprehensible that some people were able to kill many other people over a book being flushed down the toilet? Only religious fervor can lead to this - no rational behavior allows for it.

Go ahead, flush a copy of the Principia today; I promise you'll be OK.

More Cardiff Giants Please

2005-05-13T23:29:00.000-04:00

Sara and I took my parents and her parents to Cooperstown for the day yesterday. It was relaxing and fun. My Dad and my Father-in-law went to the Farmers' Museum, but unfortunately weren't able to see the Cardiff Giant. If you don't know what that is, let me quote from part of the roadsideamerica.com description:

"The Cardiff Giant was conceived by George Hull, a cigar manufacturer and atheist, after he'd spent an evening arguing with a fundamentalist minister. Hull remembered Genesis 6:4 and its reference to "giants in the earth" and wondered if people like the minister could be convinced that a large, stone statue found in the ground was actually a "petrified giant." He decided to find out."

Needless to say, the magnificent Mr. Hull made a fake and buried it. When it was discovered, most people realized it was a fake, but Christian fundamentalists defended it zealously. This all happened in 1868 and 1869.

"After years of haggling, the New York Historical Association bought the giant for $30,000 and brought it to Cooperstown, where it has resided at the Farmers Museum ... ever since."

You can bet we'll be going back some other time to see this wonder of 19th century reason.

Some Recent Reading

2005-05-13T20:36:00.000-04:00

My parents are keen readers, and have made sure to pass this on to me. When they visit us, they're officially on vacation and spend even more time reading. Some of the time I set aside to spend with them while they're here is often spent reading, and so I seem to get through books much more quickly when they're around.

In the last week I've read two books. One is Sam Harris's The End of Faith, and the other is Ian McEwan's Saturday.

Harris's book was quite enjoyable, in the sense that it feels great to have reasonable ideas, that you hold dear, repeated over and over to you. Unfortunately, this makes it all the more jarring when one reaches the parts where he overreaches somewhat. I don't want to review the book here, but Michael Bérubé has some interesting things to say about loving The End of Faith and taking issue with it, I essentially agree with Michael's broad statements (but don't have the philosophical specifics he has, of course).

I have no such ambivalence about Saturday. For my tastes, McEwan is a master. One could rave about a number of aspects of his craft, but I just love the way he creates the sense of emotion. When McEwan's characters feel guilt, shame, love, anger, obligation, or any other of the feelings that help define what it is to be human, it's not just that one sees what he means, but rather that one feels these emotions personally, immediately and viscerally. I lose count of the number of times the hairs on my neck rise, my stomach tightens, or I find myself dry-mouthed and swallowing, just by reading his prose.

In my opinion, Saturday is as good as anything he's written and, in particular, for my tastes, better even than his Booker prize winning Amsterdam. (And I haven't even mentioned his multiple passages that praise the beauty of the scientific view of the world)

Inflation and the Initial Conditions of the Universe

2005-05-11T22:22:00.000-04:00

Over at Preposterous Universe, Sean has been discussing an essay he's written about his recent work on eternal inflation and the arrow of time. In the paper, and in the comments on his post, there has been a discussion about what it means to require a sufficiently large, smooth, potential energy dominated patch of the universe in order for inflation to begin. Sean referred people to a paper I wrote with Tanmay Vachaspati and I thought that, given the current interest, it might be useful to describe that work here. This will be a little more technical than usual, but far less technical than the actual paper (hopefully).

As I first learned about inflation, the idea can be summarized as the following: the universe is born and one can say very little about it since quantum gravity (whatever that is) is undoubtedly important at extremely early times. However, after some time (approximately the Planck time), the semi-classical universe emerges, and we can begin to analyze meaningfully such things as the dynamics of field theories, and the response of gravity to them. There is no a priori reason for the universe to be homogeneous at this epoch. However, local, causal particle dynamics can act to homogenize patches of the universe. After some time, a small patch becomes homogeneous and dominated by the vacuum energy of a scalar field. This patch then undergoes inflation - a quasi-exponential period of expansion in which the original small patch expands to a size many orders of magnitude larger than the observable universe today. This expansion explains the flatness of the universe, and its homogeneity on large scales today.

Now, there are a number of models of inflation in which the above story is modified (in particular, chaotic inflation), and I'll get back to them later. For now let me focus on this claim of homogeneity in the theories I described above.

Why does inflation, as described, "solve" the homogeneity (or horizon) problem? Clearly, the idea is that the homogeneity of the initial pre-inflationary patch, explained by causal physics, is translated into the homogeneity of the larger space after the exponential expansion. At the risk of being pedantic (me? pedantic?), this can only be true if the original patch is made homogeneous by causal processes, otherwise homogeneity would once again be an assumption, albeit a less severe one.

What did we do in our paper? We first imagined that the early universe, emerging from the Planck epoch, was not inflating. To make progress we'll need a few definitions, which I'll define below in a more blog-friendly way than in the paper.

Let's focus on spherically symmetric space-times and pick an origin. Then examine spherical surfaces centered on this origin. Such surfaces can be divided into three categories in the following way. Imagine sitting on such a surface with two flashlights, both pointing radially and close together. The flashlights can both be pointing outwards (away from the origin), or both pointing inwards (towards the origin). The categories are then:

NORMAL: When the flashlights point inwards, the rays converge to the origin. When they point outwards, the rays diverge away from the origin. This is how regular parts of space-time behave; for example, points in our universe closer to us than the horizon.
TRAPPED: When the flashlights point inwards, the rays converge to the origin. When they point outwards, the rays still converge to the origin. Such surfaces can be found inside the horizon of a black hole.
ANTI-TRAPPED: When the flashlights point inwards, the rays nevertheless diverge away from the origin. When they point outwards, the rays diverge away from the origin. Such surfaces can be found, for example, beyond the horizon in our universe.

Now, back to what our paper showed. If the universe is not born inflating, then we want to imagine that, at some later time, local, causal particle dynamics yield a patch that is homogeneous and vacuum-dominated, and thus begins to inflate. The fundamental question for us was; how small can this patch be?

The main tool we used is called the Raychaudhuri equation. It describes the rate of change of divergence of close by pairs of light rays, as I described above. The equation is a little complicated but, by considering the types of light rays I mentioned above (perpendicular to spherical surfaces), and by making two further assumptions: that the Einstein equations are satisfied, and that the weak energy condition holds (matter isn't too weird), the most important consequence of the Raychaudhuri equation can be stated as

Light rays pointing inwards cannot emanate from a normal surface and cross an anti-trapped one.

What does this mean? Well, if the original inflating patch is smaller than the Hubble size of the background space-time, then, it can be shown that light rays violating the above statement must exist. Thus, we conclude that the size of the initial inflating patch is at least as large as the Hubble size of the background space-time. But this size is large compared to typical particle physics processes that can act to homogenize a region (actually, if the background space-time is radiation-dominated FRW, the Hubble size IS the causal horizon). Thus, it is very hard to see how such an initially homogeneous inflating patch might form. This is our main result.

It is possible that inflation, if it begins, leads to "eternal inflation", in which one patch gives rise to an infinite expanding space, which produces an infinite number of regions of the universe that look like ours. A full understanding of the question of initial conditions (or probabilities) in that case is partly what Sean's paper is about. Tanmay and I viewed our work as explaining what is needed for such an inflationary model to work.

The Beautiful Godlessness of Darwin

2005-05-09T17:09:00.000-04:00

It is often complained that the stark precision of science destroys the beauty and poetry of the world. To those of us who spend our lives immersed in science, this is usually at odds with our view of the discipline. However, it is probably true that we fail to capture our own feelings regarding the beauty of science in our writings about it.

What we need are more examples like the following, in which Ian McEwan, in his latest novel Saturday, describes the beauty to be found in evolution, without the need for a deity

"Kindly, driven, infirm Charles in all his humility, bringing on the earthworms and planetary cycles to assist him with a farewell bow. To soften the message, he also summoned up the Creator, but his heart wasn't in it and he ditched Him in later editions. Those five hundred pages deserved only one conclusion: endless and beautiful forms of life, such as you see in a common hedgerow, including exalted beings like ourselves, arose from physical laws, from war of nature, famine and death. This is the grandeur. And a bracing kind of consolation in the brief privilege of consciousness."

Ian McEwan, "Saturday", Doubleday, 2005.

I think this is the picture we need people to see, alongside our formulae, graphs and tight, unambiguous prose. Science as an awesome and humbling description of our world, grounded in reason, and all the more beautiful for it. I've mentioned before that fine science writers are our allies in the fight for reason in the face of nonsense. Clearly, some novelists are also on our side.

Wigan Athletic vs. Manchester United

2005-05-08T23:52:00.000-04:00

This is the kind of football fixture Britain will have to get used to after my hometown team, Wigan Athletic, earned promotion to the English Premiership division earlier today. You can read about their deciding game here. It's going to be weird and wonderful and a lot of fun for Wiganers everywhere.

Large Extra Dimensions and a Hint of Hyperbole

2005-05-08T20:28:00.000-04:00

I've spent part of the weekend thinking over some applications of an idea I worked on several years ago. This idea involves the concept of large extra dimensions, which I mentioned briefly once before. I promised then I'd have more to say on the topic, so here goes the first installment.

The hierarchy problem in particle physics is the problem of reconciling two wildly disparate mass scales; the weak scale (10² GeV) and the Planck scale (10¹⁹ GeV). This hierarchy is technically unnatural in particle physics, since, in general, the effect of quantum mechanics (here known as renormalization) is to make the observable values of such scales much closer in size.

One approach to this problem is to introduce a mechanism that cancels many of the quantum corrections, allowing the scales to remain widely separated even after quantum mechanics is taken into account. An example of such a mechanism (and the most popular one, for sure) is supersymmetry (SUSY), which I may discuss another time.

However, another perspective is to view the hierarchy problem no longer as a disparity between mass scales, but rather as an issue of length scales, or volumes. The general hypothesis is that the universe as a whole is 3+1+d dimensional (so that there are d extra, spatial dimensions), with gravity propagating in all dimensions, but the standard model fields confined to a 3+1 dimensional submanifold that comprises our observable universe. This submanifold is called the brane (as in membrane).

This is really a superstring-inspired modification of the Kaluza-Klein idea that the universe may have more spatial dimensions than the three that we observe. As in traditional Kaluza-Klein theories, it is necessary that all dimensions other than those we observe be compactified (wrapped up nice and small), so that their existence does not conflict with experimental data. The difference in the new scenarios is that, since standard model fields do not propagate in the extra dimensions, it is only necessary to evade constraints on higher-dimensional gravity, and not, for example, on higher-dimensional electromagnetism. This is important, since electromagnetism is tested to great precision down to extremely small scales, whereas microscopic tests of gravity are far less precise (although remarkable advances have been made in recent years, prompted in part by these theoretical ideas).

Since constraints on the new scenarios are less stringent than those on ordinary Kaluza-Klein theories, the corresponding extra dimensions can be significantly larger, which translates into a much larger allowed volume for the extra dimensions. This extra volume is a big deal!

You can imagine the strength of gravity as being a bit like the force due to a steady stream of water emerging from the nozzle of a hosepipe. Suppose that the water is confined, by some fancy nozzle, say, to emerge in a stream that is essentially one dimensional - a very fine stream. If you've ever fitted a tight nozzle to a hosepipe, then you'll know that such a stream is very powerful, and the force it exerts on you, if pointed your way, is very high.

Now imagine that, instead, the water is spread out to emerge in a plane (OK, that would require one fancy nozzle, but I'm sure you can imagine it). In this case, if your body is in the way of the water in some direction (the same distance from the nozzle as in the first case), it will still exert a force on you, but less than when you were being hit by the one-dimensional stream. This is because you're not being hit by all the water, but instead by a portion of it - there are other directions available for the rest of the water to go.

If we now fit a nozzle that allows the water to spread out in a spherically-symmetric three-dimensional pattern, then the force on your body will be yet weaker because there are still further directions for the water to spread.

The analogy I'm drawing here is with lines of gravitational flux, the density of which, in Newtonian gravity, describes the strength of gravity. The more directions (think dimensions) available for the water (think gravitational flux) to spread, the weaker is the force experienced.

Thus, in the large extra dimensions picture, it is the spreading of gravitational flux into the large volume of the extra dimensions that allows gravity measured on our brane to be so weak, parameterized by the Planck mass M_P, while the fundamental scale of physics M_* is parameterized by the weak scale, M_W, say.

Given this, the problem of understanding the hierarchy between the Planck and weak scales now becomes that of understanding why extra dimensions are stabilized at a linear size (~0.1 mm, for example) that is large with respect to the fundamental length scale (1/M_*). This is the rephrasing of the hierarchy problem in these large extra dimension models.

Nemanja Kaloper, John March-Russell and Glenn Starkman and I proposed a modification to the above picture, in which we argued that there exist attractive alternate choices of compactification (the way in which the extra dimensions are wrapped up). These compactifications employ a topologically non-trivial internal space - a so-called d-dimensional compact hyperbolic manifold, and throw into a new light the problem of explaining the large Planck/Weak hierarchy. It'll be fun to blog about these, but since I'd like to keep that discussion distinct from the primer above, I think I'll leave it here for now.

Friday Random Ten (Or "Mark is Lazy & Tired")

2005-05-06T23:13:00.000-04:00

I just got back from a Wonderful dinner party with my friends Dympna Callaghan and Chris Kyle. Dympna is a renowned Shakespearean scholar and Chris a historian of the British parliament. However, much more importantly, Chris is a Kiwi (New Zealander) who spent many years in England, and Dympna is from the North of England (although the wrong side of the Pennines). The dinner party guests were Sara and me and my parents, who have become good friends of Chris and Dympna during the past few visits to Syracuse.

We've had a wonderful night, with lots of Brit-talk, and an abundance of excellent food and wine. I'm feeling lazy and tired and, hence, here is my first Friday random ten, fresh from my iPod.

There It Is, Barry White
Graceland, Paul Simon
The Update, Beastie Boys
Hey Ya, Outkast
War Child, The Cranberries
Sunrise, Norah Jones
Starlight Hour, Ella Fitzgerald
Vivo Sonhando Dreamer, Astrud Gilberto
Maria, Blondie
Chyna Black, Anthony Hamilton

Blair Goes 3 for 3

2005-05-05T23:36:00.000-04:00

As I write, Tony Blair and the Labour party have just passed the 324 seats needed to win a historic third term. I guess I'm pleased, compared to the alternative. Blair's majority is looking, at this point, to be greatly reduced, as one might expect, given the circumstances.

You might have thought that Labour was confident, but one glance at Tony Blair's agent, John Burton, tells the real story.

I hope that Blair personally remembers this close shave and that the party takes it to heart and replaces him with someone else (realistically, it would probably be Gordon Brown) to at least try to acknowledge the Iraq stench that sticks to the party at present. The people who voted for Labour with noses pegged would at least feel somewhat vindicated by that.

The British Election for Expats

2005-05-04T23:16:00.000-04:00

On the eve of the British general election, there is a delightful piece by Simon Schama in The Guardian. Much of it focuses on the differences between the election seasons in the U.S. and the U.K., and will resonate with any expat reader. Here's a particularly descriptive (and laugh-out-loud funny) paragraph:

"I was a just few hours off the jumbo from Newark, New Jersey, but it felt like dropping down the rabbit hole and emerging into parish pump politics. Compared with the engorged rapture, the fully orchestrated Hollywood production numbers; the serried ranks of Raybanned Secret Service Men; the ululating good 'ole boys, the big-hair hoopla, the bra-popping, pompom waggling cheerleaders, the Spandex highkicks; the tossing ocean of flags; the relentlessly inspirational gospel songs; the banners as big as a wall; the parade of uniforms (any uniform will do - firemen, police, marines, traffic wardens, apartment house doormen); the descending chopper blades; the eventual appearance of the Awaited One to swoons of joy and exultant whoops of messianic acclaim; compared to the whole delirious cornball razzmatazz that passes for democratic politics in the great American empire, Ashford on a bank holiday weekend was utter Ambridge. Thank God. Except he too was mercifully missing from the general election."

The entire piece is punchy, humorous, full of gems like this, and more compact than his "A History of Britain" trilogy. Immediately after the end of the article, there's also a hilarious little ad for a quintessentially British show of defiance

"Time for Operation Nose Peg: hundreds of readers have requested Polly Toynbee's ingenious nose pegs to allow them to vote Labour today while holding their nose. If you are one of them, don't forget to take a picture of yourself at your polling station wearing the nose peg and G2 will publish them after the election. Email nosepegs@guardian.co.uk or send your pic to G2, The Guardian, 119 Farringdon Road, London EC1R 3ER."

Sometimes I really miss England.

U.S. Universities Presented with Outstanding Opportunity

2005-05-04T00:05:00.000-04:00

My good friend and frequent collaborator Sean Carroll has been denied tenure at Chicago. Sean and I spoke about this for a while on Friday, shortly after he'd found out, and he has just posted about it on his blog, Preposterous Universe.

I can't do real justice here to the respect I have for Sean as a scientist, independent of our friendship. He is a formidable intellect, a deep-thinking cosmologist and particle physicist, and one of the most socially responsible members of our field that I know. Sean has made important and well-recognized contributions to theoretical cosmology, while popularizing the subject through his fantastic public lectures, organizing tremendous conferences and mentoring outrageous numbers of postdocs, graduate students and undergraduates. Our collaborations have been some of the high points of my career both from an intellectual and a purely fun viewpoint. And I haven't even mentioned his wonderful G.R. textbook.

As Sean says himself, this is a sad situation for him. However, everyone within the field realizes that there's going to be a fascinating feeding frenzy as many excellent places fight over him. He's going to end up somewhere great, and wherever that is, they will be lucky to have him. I know we're going to continue to write good papers together; only the institutional affiliation will change.

Sean says blogging will be a lower priority for a while. I understand this, as I'm sure we all do. However, I think it's worth encouraging him to continue to post quite regularly. Just because Chicago has chosen to lose a world-class young cosmologist doesn't mean we should lose one of our most eloquent and prolific commentators on science and society.

Well I'll be a Monkey's Great, Great, ... , Great Grandson

2005-05-03T00:15:00.000-04:00

Science is under attack in Kansas once again. On Thursday, the Kansas State Board of Education will begin hearings into the teaching of evolution. Intelligent Design cranks had hoped to use the "debate" to elevate their thinly disguised religious agenda to the same level as established science. However, as far as I understand, many scientists who were asked to speak have refused to lend credence to this obvious nonsense. I applaud their eminently sensible choices.

The Kansas debacle is being reported in many places, but I read a particularly interesting take on it in the Christian Science Monitor, which discusses the role of brainwashed students in the fight against reason. Don't we usually put people in prison for child abuse?

A Heartwrenching Vote

2005-05-01T22:55:00.000-04:00

The British General Election will take place this Thursday, May 5th. I've mentioned before how much agonizing I've been doing about this particular election. Stories about the Labour leadership's deliberate misleading of the public about the Iraq war continue to come out, even today. I think that, to a reasonable extent, it has been established that the government both lied about the evidence, and ignored expert advice about the legality of the war. I remain disappointed and furious about this. To reward a Prime Minister for such duplicity with a third term is almost unthinkable, and to play a part in that would leave me feeling in need of a good shower.

But I'm going to do it anyway.

Although I've given this a lot of thought, and have considered as many of the issues as I can, my ultimate reasons are not subtle at all. The next Prime Minister will either be Tony Blair or Michael Howard. Despite my deep dislike of Blair and of his lies over Iraq, I can't contribute in any way to a Conservative victory.

For most of my life in England I lived under a Conservative government. In fact, an article I recently read about the Conservatives' use of some of the same political consultants as the Bush campaign, brought to mind the role of Saatchi & Saatchi in propelling the Conservative government of Margaret Thatcher to power in the late 1970s. I can't overstate what a disaster that election was for Britain. In the North West, where I lived, unemployment rose to percentages in the 20s, and some people committed suicide they were so depressed with their lives during, and about their prospects after, long-term unemployment. I was thinking this over tonight, while hanging out with my Mum and Dad, both of whom struggled and sacrificed mightily to raise my brother and me during my Father's many years of unavoidable unemployment under Thatcher. My parents made a wonderful childhood for us during those years, but the thought of what they went through to make that happen angers me even today.

When I read the Conservative party manifesto, I see nothing to make me think that today's Tories are less likely to wreak havoc on working people than Thatcher's did. Granted, Labour no longer presents as clear or attractive an alternative as it did when I was growing up. Nevertheless, when I look at the economy, the attempts to battle the class system, the attitude to Europe, the fight for workers' rights, education and healthcare, I'm convinced that life, for most of the population, will be better under Labour than under the Conservatives.

For me, at least, I need to vote in a way that will make a difference to the world as it is, not as I wish it were. So I will swallow my bile, vote for Blair, and get out a big bar of soap.

(At least, I would, if I hadn't realized too late that my Dad would be here when the election took place, and therefore wouldn't be able to cast my proxy vote.)

Teri Heads to Iraq

2005-04-30T23:26:00.000-04:00

My good friend Teri Weaver is a reporter, based in Seoul, for the military newspaper, Stars and Stripes. I know Teri from her time as a reporter on the Post Standard, here in Syracuse. She is a smart and fun woman, whose sense of humor is dearly missed around here.

Beginning in the last week in May, until July 4th, Teri will be in Iraq. She has an interesting and well-written post about her upcoming time in a combat zone on her blog, stonesoup. The whole post is worth reading. Even though it is mostly written just for her friends, I think Teri has taken time (or is just a natural) to capture the nuances of her situation in her writing. For her friends who are wondering what she'll be doing in Iraq, she tells us that

"I'll be embedded with troops all the time, probably mostly around Baghdad, but if it seems plausible, I might request to spend some time with troops near Ramadi or other parts of the country. I'll be able to choose my assignments and my locations, so I'll have to use my own judgment."

Take care of yourself Teri, and exercise that judgment well. I'll see you when we meet up in China in August.

What Do I Think About Religion? What That Guy Said.

2005-04-29T22:53:00.000-04:00

I've been planning to write a careful account of my views on religion and its role in American life. I think this is a crucial issue because now, more than at any time in recent history, our society faces an increasing threat from the forces of irrationality. As scientists, and therefore daily practitioners, we are in a unique position to stand up and defend reason and logic. We can either speak out about the current social and political climate, or we can hide our heads in the sand and hope that it goes away. However, if we do the latter, we should not pretend that we didn't have a choice when sky actually falls.

I'll probably still write my piece, but it turns out that Richard Dawkins has hired an expensive psychic to fish around in my head and then has regurgitated my thoughts, in a more eloquent style, as his answers for an interview with salon.com. So you can pretty much just read that.

As an example of Dawkins at his clearest (and, surprisingly, his most optimistic and conciliatory), he says

"You won't find any opposition to the idea of evolution among sophisticated, educated theologians. It comes from an exceedingly retarded, primitive version of religion, which unfortunately is at present undergoing an epidemic in the United States. Not in Europe, not in Britain, but in the United States.

My American friends tell me that you are slipping towards a theocratic Dark Age. Which is very disagreeable for the very large number of educated, intelligent and right-thinking people in America. Unfortunately, at present, it's slightly outnumbered by the ignorant, uneducated people who voted Bush in.

But the broad direction of history is toward enlightenment, and so I think that what America is going through at the moment will prove to be a temporary reverse. I think there is great hope for the future. My advice would be, Don't despair, these things pass."

I know that a lot of people with views on religion that are similar to mine do not like Dawkins. I've never understood this attitude. Dawkins is a hero of mine because he just comes out and makes the arguments in a clear, concise and unvarnished manner, whereas some people may prefer it if one sugarcoats the message. While I understand the sentiment, I feel that this approach can often obscure the point. This feeling is reinforced by the refreshing sensation I get whenever I read Dawkins. I get a similar feeling from reading Pharyngula.

The Gravitational Lens

2005-04-29T08:04:00.000-04:00

In the comments section of Orange Quark, and a number of other physics blogs, I frequently see questions about the latest interesting paper that has popped up on the physics archive. Virtual spaces where one can discuss such papers are not well developed, but some do exist; for example, the CosmoCoffee forum. It seems to me that, with the increasing number of papers appearing daily, there's a market for sites with their own selection criteria, which winnow the number to a manageable one. Of course, one also wants the option to skim all the abstracts from four archives daily, as I do now.

As of yesterday there is a new contribution in this field. The Gravitational Lens is a short newsletter highlighting recent work in gravitational physics (all gravitational physics, not just waves) that is of broad interest. It will be posted every two months, and you can be notified of new issues by subscribing to the email distribution list.

The Editor-in-Chief of The Gravitational Lens is the talented Michelle Larson, who is the Deputy Director of the Center for Gravitational Wave Physics at Penn. State University. As a member of the editorial board, my role in this is to inform Michelle about any recent preprints (say, from astro-ph or gr-qc) that are related to gravitational physics, and lend themselves to highlighting, in a manner accessible to students and researchers in all areas of physics.

If you're interested in gravitational physics, I encourage you to visit The Gravitational Lens every couple of months and take a gander at what's new. If you see new papers on the archive that fascinate you, feel free to drop me a comment or email - perhaps they'll end up being discussed there.

Most Scary: Altostratus or Cumulonimbus?

2005-04-28T23:23:00.000-04:00

I didn't see this in the U.S. press, only in the Guardian. Did I just miss it? In any case, there's something pretty funny about it. You can read it for yourself, but I'll give you a taste with the headline

"Incoming cloud forces Bush into safe bunker"

An Eventful Day

2005-04-27T08:27:00.000-04:00

Today is going to be very busy, and I'm quite excited about it, but won't get much blogging time. This evening is the opening reception for Stage I of the Cosmic Connections exhibit at the Milton J. Rubenstein Museum of Science and Technology (MoST) in Syracuse, a topic I've mentioned before. I need to prepare a few remarks for the opening, and get down there early to reassure myself that everything is ready for prime-time.

Much more importantly though, my Mum and Dad are arriving from England this afternoon. I'll be picking them up at the airport in a few hours, but first need to do some serious shopping. Middle-aged English people will wither and die rather quickly when removed from their homeland, unless their hosts are careful to stock up on life-giving essentials; most importantly tea. It's a bit like the Jurassic Park dinosaurs, that couldn't leave the island because they were dependent on a certain drug being delivered regularly. There are a few other important items such as bread, butter, bacon, Boddingtons,..., but tea is the important one (Just joking Dad!).

I've been looking forward to my parents' visit for months now, so I'm delighted they're finally arriving. Although I love living in the U.S. (most of the time), it's difficult to be so far away from my parents and brother, and visits like this are essential for us all. Now, I'd better go and check on our tea supplies.

Some Negativity About Negative Tension

2005-04-26T19:41:00.000-04:00

Well, I'm going to take a break from going on about science under attack and return to some interesting physics, for today at least.

Yesterday we had an interesting seminar by Paul Smyth, who is a graduate student at Imperial College, London, studying with Kelly Stelle. Paul’s talk was titled “The Stability of Harava-Witten Space-times”. He was concerned with the implications of the negative tension branes required by some extra-dimensional models, both those arising from string theory and those appearing in some more phenomenological models. In Paul’s seminar, he discussed a detailed analysis of the energy of such braneworld space-times in 5 dimensions, and demonstrated that they are stable, using a non-perturbative positive energy theorem.

This, and related questions have interested me for a while, and Don Marolf and I wrote a paper that I really liked about a related physical setup. I thought it might be fun to recount the general ideas here.

An interesting possibility, that has seen new life in the last seven years or so, is that our three familiar spatial dimensions may exist as a submanifold of a higher dimensional space-time. Common to most of the modern incarnations of this idea is the condition that all interactions other than gravity be confined to our submanifold, or brane. Since departures from 3+1 dimensional gravity are relatively difficult to constrain compared to those of other forces, this permits significant freedom to modify the gravitational interactions in the extra-dimensional space. It is in this modification of gravity, and of the extra dimensions themselves, that recent approaches differ from one another.

In many of the proposed models, the hierarchy problem of particle physics – how is the large difference between the weak scale (100 GeV) and the Planck scale (10¹⁹ GeV) protected from the destabilizing effect of quantum corrections - is recast by bringing the fundamental mass scale of physics down to the weak scale. The large Planck mass observed on our brane is then a derived quantity, the size of which arises from the relatively large volume of the extra-dimensional manifold.

One specific hurdle that extra-dimensional theories must clear is that the brane-bulk system should be a consistent, stable solution to Einstein gravity. For those constructions that include negative-tension branes, this can pose a particular problem, although perturbative dynamical objections can be overcome by placing the offending brane at a point of special symmetry in the extra-dimensional space, known to aficionados as an “orbifold fixed point”.

Nevertheless, Don and I were interested in the possibility that there might be nonperturbative instabilities of such a space-time. We though there might be because of a simple (and, it turns out, naïve) thermodynamical argument.

This comes from the generalized second law of thermodynamics, which states that the total entropy in matter and black holes does not decrease. The entropy of a black hole is proportional to the area of the event horizon. Therefore, any process that leaves the entropy in matter fixed and decreases the total area of black hole horizons, leads to a violation of the generalized second law.

It is important to know that the area of a black hole event horizon increases when positive energy crosses the horizon, and decreases when negative energy crosses the horizon. Don and I were intrigued by the question: what happens if a black hole, initially far away from a negative tension brane, falls towards the brane and captures some of the brane within its horizon? One might expect that the generalized second law could be violated in this way, since the part of the brane that is swallowed by the black hole carries negative energy across the horizon.

Because the central issue can be muddied by questions involving gravitational radiation (and, frankly, because to go further than this seemed much harder) we considered a lower-dimensional system - a negative tension 1-brane in a 2+1 dimensional space-time – because gravitational radiation does not arise in lower dimensions. What we discovered in analyzing this system was something more dramatic (at least on the face of it) than a violation of the generalized second law.

In 2+1 dimensions, the only black holes are the so-called BTZ black holes, named after their original discoverers Maximo Banados, Claudio Teitelboim and Jorge Zanelli. These black holes arise only in space-times with a negative cosmological constant, the so-called Anti de-Sitter (AdS) space-times. This turned out to be particularly appropriate, because the kinds of brane-world constructions that people have worked on typically require an AdS space-time, for other reasons.

In the main part of our work (this is the bit where the cartoon caption reads "and then a miracle happens"), we made use of a certain amount of cute mathematics, involving the fact that both a BTZ space-time and a negative tension brane space-time can be constructed as quotient spaces of AdS. I certainly won’t go into this here. Rather, I’m going to hope that it suffices to say that this enabled us to construct a general exact solution describing the collision of a black hole and a negative tension brane at one of these points of special symmetry

What we found was catastrophic. The endpoint of this evolution is not, in fact, an equilibrium configuration, but instead is a space-like singularity (similar to the `big crunch' of closed cosmological models with only ordinary matter content). What we discovered, therefore, was a non-linear dynamical instability of gravitating negative tension branes at orbifolds – in effect, the entire space-time outside the black hole collapses when the brane is located at an orbifold fixed plane. Because BTZ black holes can form dynamically from the collision of matter, we also expect non-linear instabilities with negative tension branes in the presence of matter fields, even if no black holes are initially present.

The obvious question to ask is whether the same sort of singularity that we found in 2+1 dimensions also occurs in higher dimensional cases (which are of real interest). For a number of reasons, examples such as this are not sufficient to argue convincingly for a dynamical instability in higher dimensions. That's for future work, and I think I may even have interested Paul in the idea, at least a little.

It's worth mentioning that the ways in which orientifold constructions in string theory obviate this proof is a very interesting story in its own right. If you have the fortitude for it you can read about that in a nice paper by Don Marolf and Simon Ross.

So what is the bottom line of our work? It’s that an orbifold boundary condition may not, by itself, be sufficient to render negative tension branes stable. As a result, if use is to be made of negative tension branes in various models, it is necessary to show that the particular branes being used are immune from these effects. Within string theory this is probably not a problem, but phenomenological models might not be immune.

Well, that was a little more technical than usual, but since I've been thinking back over these ideas recently, I thought I'd provide a short overview. Come to think of it, there's a bunch of less technical and very fun things I'm itching to tell you about extra-dimensional models. I'll get into them soon.

Unlimited Love (for Influencing Desperate Scientists)

2005-04-25T23:42:00.000-04:00

At Syracuse we have an aggressive Office of Sponsored Programs, tasked with getting our grant applications in on time, making sure they conform to the standards of the funding organizations, and informing us of new funding opportunities. Generally, they do a great job.

Imagine my reaction therefore, when I received the following today.

Secondary School Faculty Invited to Enter Course
Competition on Unselfish Love

Deadline: July 15, 2005

The Institute for Research on Unlimited Love - Altruism,
Compassion, Service ( http://www.unlimitedloveinstitute.org/ ),
which was established through a grant from the John
Templeton Foundation ( http://www.templeton.org/ ), has
announced "Unto Others: Scientific and Religious Perspec-
tives on the Love of Neighbor," a course competition for
secondary school faculty.

The competition encourages academically rigorous secondary
school courses that focus on unselfish love of neighbor as
a spiritual and practical ideal. The winning courses must
combine the study of unselfish love as understood within
(a) spiritual traditions and (b) scientific frameworks,
such as physics, cosmology, evolution, biology, political
science, the social sciences, and health.

Faculty in religious studies and/or theology, the
humanities, and the sciences are encouraged to apply.
Courses co-taught by two faculty members representing
religion and science might be especially compelling in
some cases, but team teaching is by no means imperative.
In addition to new individual course development, it is
possible to apply on the basis of refocusing an already
existing course on the theme of unselfish love with
significant attention to religion and science. In some
cases, several faculty teaching in an integrative core
humanities course might work together to include the
topic as a major and sustained theme.

Ten awards of $5,000 will be made.

Applicants can review the full course competition
description at the Institute for Research on Unlimited
Love Web site.

Before my upcoming post on topics like this, it might help to read Sean's take on a related issue. Day by day, it just keeps getting worse and worse. What we desperately need is an absurdly rich philanthropist, who wants to fund a prize for, and research into, the relationships between (not the compatibility or incompatibility between) reason and dogmatic belief systems. Of course, the outcome is already clear and doesn't agree with the preconceived notions of the Templeton Foundation.

Science, Scientists and the American Way of Life

2005-04-25T07:23:00.000-04:00

Science, to me, is a strong uniting force. I've discussed, and often collaborated on, projects with people from a long list of countries, and never once in these discussions have issues of politics, race, economics, history or religion intruded on us. Sure, we talk about all these things over a beer afterwards, but the camaraderie we feel because of our common scientific goals, and shared experience in working towards them, ensures that these conversations are, almost always, constructive and civil.

For reasons like this, I am not one of the people who need to see U.S. dominance in science. I don't like the combative implications of the word, and I think its use misses the point of science as a unifying endeavor.

However, there are a host of economic, medical, educational, social and security reasons that the nation desperately needs a large, well-educated and well-supported scientific base. That's why the current turn away from science and reason and towards superstition and dogma in this country terrifies me. I don't think it is an overstatement to say that, if it continues unabated, this trend will bring about such a fundamental change in the intellectual constitution of the nation as to threaten to break the backbone of American life. I say this because maintaining a high standard of living for Americans is deeply connected to our country's investment in the scientific and technological research that will dominate the economy of the future.

Obviously, I have many longer posts planned about this, but I was galvanized to mention it today after reading two sobering posts on other science blogs. Over at Dynamics of Cats, Steinn Sigurdsson has a well-written piece about the inverse brain drain. Meanwhile, Gordon Watts writes eloquently about the impact of new restrictions on foreign graduate students on his Quantum Diaries blog.

Although there are many subtleties involved in what's going wrong in the U.S., ranging from the impact of the extreme right in politics, to the absurd way in which appropriations need to be reconfirmed year after year, the bottom line for the U.S. can be expressed quite simply (if not maturely); you snooze - you lose!

Baseball, Physics and Science Journalism

2005-04-24T21:07:00.000-04:00

We're three weeks or so into the baseball season now, and although the Cleveland Indians are only third in the AL Central, with an unremarkable 8-11 record, I'm still enjoying the feeling of summer in the U.S. that baseball brings, and that I've blogged about before.

Much has been written about the physics of baseball, and I am certainly no expert on it myself. However, there is a fascinating article about pitching in the current issue of American Scientist, the science and technology magazine, published by Sigma Xi, The Scientific Research Society. One of the authors, David G. Baldwin, seems like an interesting guy; according to his bio, he

"...pitched for the Washington Senators, Milwaukee Brewers and Chicago White Sox during the 1960s and 1970s. Following a 16-year professional baseball career, he earned a Ph.D. in genetics and an M.S. in systems engineering from the University of Arizona."

This is exactly the opposite of the way I'm planning to do it, as soon as this rotator cuff problem eases up and my contract with the Physics Department softball team expires.

I'm a big fan of American Scientist. They do a disciplined and careful job of covering some of the most interesting issues in modern science. One reason for this is their wonderful editor, Rosalind Reid. Rosalind was the Journalist in Residence at the Kavli Institute for Theoretical Physics (KITP) at the University of California, Santa Barbara, when I was spending my sabbatical there in late 2003. She ran a number of fascinating seminars and workshops about various aspect of science writing, spent a lot of time talking to the scientists, and was generally a fun person to have around.

The Journalist in Residence program is a tremendous idea. Previously, I've gone on at length about the importance of serious science journalism, and I think that any way in which we can provide journalists access to scientists helps further this goal. The nice thing about the KITP program is that it also provides a forum in which scientists can learn a lot more about the process of science journalism, and science writing in general. In my experience, this helps scientists to be better writers themselves, and helps them to appreciate the processes that science journalists go through in deciding whether a story idea is interesting and topical.

Now, more than ever, with science under attack, we need opportunities, such as this, to train with our allies.

"Pop her ... Pop her again"

2005-04-23T09:01:00.000-04:00

South Carolina lawmakers have a controversial (in South Carolina, apparently) bill in front of them. It's called the "Protect Our Women in Every Relationship (POWER) Act", and is designed to strengthen laws against domestic violence. The lawmakers were taped at their committee meeting discussing this. According to Salon.com

"Rep. John Graham Altman asked why the bill's title "Protect Our Women in Every Relationship (POWER)" just mentioned protecting women.

Judiciary Committee Chairman Jim Harrison suggested calling the bill the "Protecting Our People in Every Relationship Act," or "POPER," ...

A voice on the tape is heard pronouncing it "Pop her." Then another says "Pop her again," followed by laughter."

The progressive Mr. Altman was later interviewed on WIS-TV and commented

"I do not understand why women continue to go back around men who abuse them," ... "I mean, you women want it one way and not another,"

Indeed. Imagine wanting both to be treated as equal partners with equal opportunities and, at the same time, wanting not to be beaten to a pulp by their husbands! I can almost hear the soft swish of knuckles against carpet as the above quotes were uttered.

Hey, "you women" in South Carolina! Can't you get rid of this guy at the next possible election? As Rep. Gilda Cobb-Hunter, a Democrat who sponsored the bill, said,

"And they wonder why we rank in the bottom on women in office and we lead in women getting killed by men,"

The Role of Science in Policymaking

2005-04-22T08:29:00.000-04:00

As part of our celebration of the World Year of Physics, we had an unusual, but very good, colloquium in the physics department yesterday. The speaker was Mitchel Wallerstein, who is the Dean of Our Maxwell School. Mitch is a very experienced guy and a talented speaker. In the past he has been the Deputy Executive Officer of the National Academy of Sciences, and was Deputy Assistant Secretary for Counterproliferation Policy in the Defense Department. His topic was Nuclear Proliferation and Nuclear Terrorism: Two Dangerous Scenarios of the Post-9/11 Era. The talk was fascinating for at least two reasons. Firstly, it was packed full of information about nuclear weapons programs over the last 60 years, detailing which countries had ever had such weapons, which had started active programs but abandoned them, and which countries had at least openly discussed the option of setting up a weapons program. There were some surprising (to me) entries on that list, such as Sweden and Switzerland. The second reason I enjoyed the talk is that it gave one some limited insight into how issues like nuclear weapons, which physicists discuss frequently and heatedly among themselves, are viewed by authorities in a different sphere - that of public policy.

Mitch teaches a course next semester titled International Security and Asymmetric uses of Force, which sounds fascinating (if scary). I'm even toying with asking him if I might audit it and, if I did so, I would certainly blog about it. The course description reads

The end of the Cold War and the emergence of the United States as the sole remaining superpower—the only one with truly global reach and overwhelming technological superiority—has forced state actors and non-state actors alike to fundamentally rethink basic conceptions of international security. Indeed, perhaps the principal lesson of the recent military actions in Iraq, Afghanistan and the Balkans is that, for the foreseeable future, there is no prospect for deterring, much less prevailing over, the United States through conventional alignments of military power. Most state actors have now recognized that such direct confrontations are an almost certain recipe for the defeat of the weaker party or parties.
This course will explore the theoretical, doctrinal and policy implications of this new reality, focusing in particular on the emergence of asymmetrical uses of force as a rational response by those unable to counter the U.S. through conventional means. After laying the conceptual groundwork through an examination of the contemporary (and likely future) international security environment, the course will explore in detail a variety of asymmetrical threats, including the use of weapons of mass destruction (nuclear, biological and chemical weapons), cyber-attacks, attacks on civil infrastructure (transportation, communications, electrical grids, etc.), attacks on agriculture, and others.
The course will be taught as a seminar, and enrollment will be limited to encourage class discussion. Students should expect an extensive reading list and will be evaluated, in part, on the basis of their class preparation and participation. Each member of the class will be expected to prepare a policy memorandum to the National Security Council inter-agency process concerning a selected asymmetric vulnerability and to participate in a group presentation. There also will be a second major writing assignment at the end of the semester that will take the form of either a scholarly paper or a take-home final exam.

Not the kind of language we physicists are used to!

Yesterday morning I served on a Ph.D. thesis defense committee. The candidate was Belkis Cabrera, one of our best graduate students. Belkis worked for Don Marolf, studying various aspects of string theory and gravity, and has been out at Santa Barbara with him for the last year or so. She did a great job of the defense and we were delighted to pass her. However, I mention this here not because I want to talk about string theory, but because of what Belkis is going to do next.

For the next year she will be a Science Fellow at the Center for International Security and Cooperation at Stanford. This is a big step for Belkis. She is undoubtedly talented enough to continue on in a successful career in physics, but has decided that, for the meantime at least, she would like to get some experience in an entirely different realm. While I will miss Belkis for however long she is gone from the scientific research community, I am delighted to see such highly trained and scientifically knowledgeable people entering fields in which they may, ultimately, be able to have an impact on government policy. I'm even more convinced of the desparate need for such people after my disappointing experience listening to John Marburger speak, as I mentioned a few days ago. It is wonderful to educate people who go on to be professional physicists, doing fundamental research in our own, or other, fields, and pushing back the boundaries of human knowledge. As I've mentioned when discussing my own graduate students, this makes me very proud. However, I think we need to do everything we can to place people with a sound understanding of the scientific method in policymaking positions. Few people realize how much science pervades almost every aspect of our lives and, consequently, the potential for catastrophe when politics trumps good science.

I'm thinking of these issues particularly today, on Earth Day, while the New York Times is reporting that a Bush Administration's climate change study ignores many areas it is required to cover by law.

The Creationist Classroom

2005-04-20T21:32:00.000-04:00

This via Aferensis. The Creationist Classroom is a short movie which, as far as I can tell, is promotional material for The End of Faith: Religion, Terror and the Future of Reason, by Sam Harris. It made me giggle, then cry.

Party Lines

2005-04-20T19:33:00.000-04:00

When you're appointing someone to an important post, it's crucial to openly discuss the relevant issues, and not hold blindly to your dogmatic views. This rarely happens in practice of course. Nevertheless, yesterday, in the process to consider the nomination of John Bolton for U.S. Ambassador to the U.N., there was even some dissent from Republicans. For example, as the BBC reports,

"... in a fractious meeting on Tuesday, one Republican senator sided with Democrats demanding a fresh hearing to air allegations that Mr Bolton was a "serial bully" who intimidated junior members of staff."

and

"Senator George Voinovich, a Republican from Ohio and not one of those who had previously questioned the nomination, said he had "heard enough today that gives me some real concern about Mr Bolton".

It'd be nice if there were more opposition to out-of-date, contentious appointments, but you can't bank on it.

Comments on Orange Quark

2005-04-19T20:45:00.000-04:00

I have just switched over to Haloscan for commenting, motivated partly by a request from Abbas Raza (of 3quarksdaily) for trackback capability. Unfortunately, as a result, blogger comments have disappeared from my blog. Thanks to all of you for your comments. I think your future ones will show up, so I hope you will continue to post your insights, advice and criticisms here.

Coming Soon to a Pharmacy Near You?

2005-04-19T08:10:00.000-04:00

A pharmacist in California refuses to fill the prescriptions of AIDS sufferers, because that would be interfering with God's plans for gays. Another pharmacist, in Michigan, won't provide arthritis medication, because gnarled hands are God's way of stopping masturbation. A third pharmacist, in Florida, refuses to fill Viagra prescriptions, because, after their child-bearing years are over, God does not intend women to have to put up with the advances of their wrinkly old husbands.

(OK, these aren't real. I mean, they'd be ridiculous wouldn't they? I'm just blowing smoke up certain conduits. However, it's white smoke, not black, which means a punch line has been chosen.)

Now read this.

The Importance of Serious Science Journalism

2005-04-19T00:05:00.000-04:00

On my last evening in Tampa, I sat up very late having a few drinks and discussing physics and related topics with Sean, Don Marolf, Wendy Freedman, Eanna Flanagan and a few other people. One was was K.C. Cole, who is one of the country’s best science journalists, and a wonderful writer in general - she was awarded the 1995 American Institute of Physics Award for Best Science Writing. You should check out her books, for example The Hole in the Universe: How Scientists Peered over the Edge of Emptiness and Found Everything. We were also joined by David Harris, who is a physicist turned science journalist, and who is Editor-in-Chief of the excellent Symmetry magazine, jointly produced by Fermilab and the Stanford Linear Accelerator Center (SLAC).

When I give public lectures, or speak to non-scientists at parties, or on airplanes, or at other social events, I find that people are, in general, fascinated by physics, particularly cosmology and particle physics. There seems to be a genuine hunger out there for direct contact with cutting edge research. A crucial role in feeding this hunger is played by well-written science reporting, of the kind that K.C. and a number of other writers provide. Their craft is not a simple one, and most certainly does not merely involve regurgitating what scientists write, but in a “dumbed-down” way. Rather, these people spend immense amounts of time agonizing over the physics, trying to understand the subtleties, avoiding the myriad pitfalls that can make a science article misleading, and interacting with scores of scientists to get the story right. I have a great deal of respect for what they do and think they provide a service that a civilized society deserves.

So you can understand why I find it so disturbing that K.C. feels that the number of dedicated science writers actively employed in the United States in dropping. To give just one significant example, Tom Siegfried has been let go as part of a large staff cut at the Dallas Morning News. Tom is an immensely talented science writer, who deftly tackles hard topics in his columns. As the American Journalism Review puts it, the paper

"... killed its weekly personal technology section and eliminated a weekly science section (firing three of six staffers) that had won numerous accolades and prizes. Those prizes include a National Association of Science Writers award that was being announced even as one of the winners, the esteemed writer and editor Tom Siegfried, was losing his job."

I think a reduction in the number of science journalists is a serious problem. It’s not just because I want people to read all about the cool things that are going on in my field (although I admit, that’s a small part of it). As our world becomes increasingly complex, crowded and interconnected, a basic understanding of science and technology is an essential requirement of an educated electorate. We are already facing a host of issues - stem cell research, genetic engineering, climate change, the energy crisis, weapons of mass destruction, missile defense - just to give a few examples, that cannot be understood without an appreciation of some basic scientific issues. At the same time, we are constantly bombarded with nonsense and pseudoscience that preys on the scientifically uneducated - astrology, alien abductions, homeopathy, magnetic therapies, perpetual motion machines and many, many more.

Already it is next to impossible to find a sensible discussion of science on network television, where many people get their “news”. If we lose responsible science writing from print journalism as well, I think that’s a huge blow. How are members of the general public supposed to make rational decisions about the policies of government if they don’t know the first thing about the technical facts that underlie many of them? It’s clearly impossible. Obviously all newspapers can’t employ a full time science journalist. However, if you are reading this and you live in a large city with a newspaper that you think doesn’t contain enough science and technology reporting, I encourage you to write letters to the editors. Tell them what you want and why it’s important. Other, like-minded readers may see your letters and join in the call for more quality science journalism.

In the in-flight magazine on my flight back home, there was a lengthy article in a section called Informed Sources, purporting to explain how acupuncture “works”. Much of the article is devoted to explaining the function of the Qi, or life force, that flows through all people. Check out this quote

"Writer James Swan had badly injured his shoulder while halibut fishing near Homer, Alaska. He wrote a column about treating his injury through acupuncture. `In traditional Chinese medicine,' he says, `an injury is seen as the result of multiple causality and a symptom of overall imbalance in Qi, caused by excessive or weak flows of Qi from or to internal organs.… From this perspective, when I was injured I was fighting seasickness, so my stomach meridian was weak. It was cold, and the choppy seas were somewhat frightening, causing weakness in the kidney meridian, as the kidneys are associated with fear. When you are frightened, your breathing shallows, producing less Qi, so the lung meridian would also be weaker. Accordingly, these external conditions made the shoulder weaker and injury more likely to occur.' "

Real science writers please help us - we need you now more than ever!

Favorite Quote of the Day

2005-04-18T18:50:00.000-04:00

Via Chris C Mooney, from the description of the DVD, Arguments Creationists Should NOT Use, on the Answers Bookstore creationist website

"Bottom line: hold “facts” loosely and focus intensely on God’s written Word as the absolute guide to evidence interpretations!"

Well, at least they just come right out with it.

The Cosmology Report from Tampa

2005-04-18T18:04:00.000-04:00

I’m on my way back from Tampa, blogging from the airport again. I have found this to be a very productive trip. A conference like this one, with a large number of attendees, has many talks and events. It is easy to spend the entire time rushing around from talk to talk, trying to see as many interesting topics as possible. However, I don’t get the most out of conferences that way. These days I pick and choose the talks I really need to see, plus a few at which I’d like to show support for colleagues or students. The rest of the time I spend meeting and discussing with colleagues. Sometimes these are preexisting collaborators and other times they aren't, but the conversations lead to new collaborations.

On this trip I attended a number of interesting talks; Rocky Kolb on Einstein’s Cosmic Legacy; Don Marolf on Quantum Gravity; Konstantin Matchev and Richard Schnee on Dark Matter; Rachel Bean on dark energy perturbations, to name just a few. Plus, as I mentioned in yesterday’s post, I also went to the Scientific Integrity in Government session.

I had a lot of fun in the Cosmological Constraints on Theories of Gravity and Fundamental Physics session, in which I delivered my invited talk on Theories of Cosmic Acceleration. What I enjoyed most about this session were the excellent talks by the other two invited speakers. Arthur Kosowsky (currently of Rutgers University, but soon to move to the University of Pittsburgh) gave a wonderful talk on the possibility that modifications of gravity might play a role in explaining the puzzles that one usually explains with dark matter. This idea usually goes under the name MOdified Newtonian Dynamics (MOND). First proposed by Milgrom, it invokes a change to the gravitational force law at a specific scale, altering the dynamics of galaxies and providing a stunning fit to galaxy rotation curves. This is by no means a popular idea, but it is fascinating that the fit to rotation curves is so successful. One reason that people initially did not spend much time on MOND is that, in its original incarnation, it is merely a phenomenological modification of Newtonian gravity and, as such, wouldn’t explain other observations that are explained by dark matter, such as gravitational lensing of galactic clusters. However, in the last year Jacob Bekenstein has formulated a covariant version of MOND. While his model is not exactly pretty, it has a honest-to-goodness covariant Lagrangian, and so one can, in principle, calculate all the implications of the theory, not just the rotation curves.

Hiranya Peiris from the University of Chicago then gave a tremendous talk on the Cosmic Microwave Background (CMB) radiation, describing how precision measurements of the fluctuations provide constraints on models of the early universe. Hiranya is the right person to do this, since she was the first author on the paper deriving these constraints from the WMAP data. .

Lots of fun physics packed into three busy days. Now back to Syracuse, where tomorrow it will be 77 degrees and beautifully sunny.

Science and Government

2005-04-17T15:40:00.000-04:00

In general I'm enjoying my time in Tampa and will post a longer description of the conference and its highlights when I return to Syracuse. This is just a short posting to get something out of my system.

I just got out of the session on Scientific Integrity in Government, in which the panelists were Kurt Gottfried, John Marburger and my friend and collaborator, Lawrence Krauss. I missed Gottfried's talk, but got there in time to catch most of Marburger's and Krauss'. Krauss discussed the appalling record of the current administration with regard to suppressing, twisting and misusing scientific data and opinion. Marburger is the White House Science Advisor and he faced a number of questions about this in the Q&A part after the talks. While he was gracious and polite, I really felt that his answers were dismissive of the well-documented and heartfelt concerns of many serious scientists. The questions from the audience were fine enough, but I don't think they got to the heart of the problem. I wanted (but time didn't permit) to ask Marburger a more wide-ranging question.

Lawrence had raised the point that 45% of Americans don't think that evolution is correct, and had pointed to well-known cases of government officials, both inside and outside the administration, who echoed that sentiment. I wanted to ask Marburger about the extent to which highly-placed people like himself, who believe themselves to be advocates for science, were consulted about issues such as this, and if so, how, if at all, they responded. This is something that is, quite honestly, a mystery to me. How does a scientist work in an administration headed by a president who thinks the jury is still out on evolution? I'm curious to know what he thinks about this and am sitting here somewhat frustrated by the whole session. Still, I feel somewhat better for having written this down.

Propagation of the Species

2005-04-15T18:55:00.000-04:00

I’m blogging from the USAir club in Philadelphia airport (although it may only get published later), where, due to a delay, I have a lengthy layover on my way to Tampa. Despite the flight delay, I should arrive in Tampa by 6pm and intend to find a good, quiet restaurant in which to eat dinner while working on my talk for tomorrow.

Yesterday turned out to be a very good day indeed. I currently have three graduate students and one postdoctoral researcher working with me. It is true, I think, that individual physicists, be they students, postdocs, or faculty members, play the major role in determining the quality of the work they do, and therefore their career trajectories. However, there are, of course, many other contributing factors, and graduate or postdoctoral mentoring is one of them. This year, my postdoc, Damien Easson, and my senior graduate student, Antonio De Felice, have both applied for postdoctoral positions. While I have fully expected all along that they would be offered good jobs, I have still been a little anxious on their behalves (OK, fair enough, and for myself, because of my role in their careers) during the application season. As of yesterday though, I can relax, because they’ve both accepted excellent positions. In the fall, Damien will be a postdoc at the Institute for Particle Physics Phenomenology at the University of Durham in England, and Antonio will take up a postdoc at Sussex University, also in England. These are both great places to do particle cosmology and I am delighted.

Mentoring graduate students and postdocs is something that one is not formally trained to do in graduate school. This means that, often, one’s primary influence is one’s own advisor and this can either be a very good or a very bad thing. I consider myself to have been extremely fortunate, in that my Ph.D. advisor, Robert Brandenberger, is a wonderful role model, who treats all his students well and works hard to make their careers succeed. I know of many other people with the opposite experience.

I don’t really know where I sit on the spectrum of advisors, but I do know that I worry a lot about this part of my job. I find Ph.D. mentoring quite difficult. With my own projects I just have ideas and plough ahead into them. Sometimes they work out. Mostly they don’t. This is fine, of course, because it only involves me. However, with students, I continually worry that the projects I set them will turn out to be either trivial, or too difficult, or just silly. Indeed, on occasion, each of these results has happened.

In any case, this year I'm celebrating because everything has worked out well. Let’s see how things go in future years.

Theories of Cosmic Acceleration

2005-04-14T20:19:00.000-04:00

I fly out to Tampa early in the morning to give an invited talk on Theories of Cosmic Acceleration in the Cosmological Constraints on Theories of Gravity and Fundamental Physics session at the April meeting of the American Physical Society. Sean (of Preposterous Universe note) is convening this session, and it'll be nice to see him and possibly even make some progress on our ongoing projects.

I'll be discussing a variety of ideas about what could be driving the recently observed acceleration of the universe. There are three broad classes of approaches. The first is that cosmic acceleration may be due to a pure cosmological constant. The second assumes that the true vacuum energy of the universe vanishes, and that the dynamics of some exotic matter component, such as a scalar field, might be driving acceleration. This approach is like having a version of cosmic inflation happen in the late universe, and goes by the name quintessence. The final approach is again to set the vacuum energy to zero, and then to have a long-range modification of General Relativity be responsible for cosmic acceleration.

At various times I've worked on aspects of each of these approaches, but most recently the modified gravity one. Sean Carroll, Michael Turner, Vikram Duvvuri and I had our own idea of how to modify gravity to make cosmic acceleration happen (we later elaborated on it with my student Antonio De Felice and my postdoc Damien Easson). We considered adding inverse curvature terms to the Einstein-Hilbert action so that when all matter dilutes away, the universe cannot approach flat space-time. Our initial model was constructed to affect the universe on large scales (the Hubble size). However, gravity is a tricky topic and it turns out that there is also an unavoidable effect at smaller, solar-system scales, which leads to critical constraints on our model. One such constraint arises from precise measurements of the timing of communications signals from the Cassini mission (man those robotic missions do some good science!). There have been some suggestions that modifications of our models (using more complicated versions of what we did, while trying to retain the main idea) can evade the constraints. However, I actually don't see how these can be correct and, at present, I don't know how to overcome the obstacles. My collaborators and I are fine with that though - this is how science is meant to work.

There are some other suggestions of how to modify gravity to obtain late-time cosmic acceleration. One belongs to the fiendishly inventive Gia Dvali and collaborators, who have an extra-dimensional brane-world model, known as DGP gravity, in which gravity becomes five dimensional at very large distances. This model can also exhibit shorter-range effects in addition to the large scale ones that provide cosmic acceleration. However, my understanding is that these models evade current bounds, but may be testable with precision tests of gravity in the near future. This has been worked on by, among others, my good friends Glenn Starkman and Arthur Lue.

I'll be discussing all these ideas, and more, in my APS talk, assuming that I finish writing it in time for the Saturday afternoon session. It's going to be a busy flight tomorrow.

Cosmic Connections

2005-04-13T13:20:00.000-04:00

This afternoon I'm heading down to the Milton J. Rubenstein Museum of Science and Technology (MoST) in downtown Syracuse, to walk through an upcoming exhibit. I am a co-PI on a $600, 000 National Science Foundation grant to create an entire cosmology exhibit, called Cosmic Connections, which will be a permanent part of the museum.

Stage one of this project is now almost complete, with the grand unveiling in two weeks' time. For the past couple of months a lot of construction has been going on in the space and, since I am really involved more with the conceptual side, I haven't had a good look at it. If the exhibit looks anything like the elaborate models we had, then I'll be very excited. To ensure a professional and coherent design, we collaborated with two classes of students in the design program at Syracuse. Getting physicists and designers to work well together was a challenge, but I think it worked out pretty well and we learned a lot from each other.

The opening reception, at which I'm giving a short cosmology talk, is on the evening of April 27th, and I intend to post some photographs of the exhibit soon afterwards, with a more detailed explanation of what we've accomplished so far. What I really want to show you are the fantastic glass sculpture of the galaxy that we have, and the hologram of large-scale structure in the universe (although this one will be challenging). The latter provides a three-dimensional-looking representation of an actual N-body simulation of the distribution of dark matter. I think they both look fantastic, and I'll give you all a chance to judge them for yourselves very soon.

The Abridged Bérubé

2005-04-12T08:07:00.000-04:00

You've got to see this to believe it! After a pants-round-the-ankles paddling by Michael Bérubé in an email "debate", that odious whackjob David Horowitz, champion of the "Academic Bill of Rights" Trojan horse, posted an edited version of the exchange, which, let's say, doesn't accurately convey the rosy glow left on Horowitz's cheeks.

Fortunately Michael kept the entire text of the debate and has posted it on his blog. Horowitz now claims this was a mix-up and says he'll post the entire version soon (with another rejoinder from Horowitz. Does Bérubé get to reply to this additional statement?) I don't believe his explanation.

In British Politics, Be Careful What You Wish For

2005-04-11T17:58:00.000-04:00

A few posts back I discussed how torn I am about the upcoming British general elections. My central issue is the judgment that Tony Blair deliberately misled the public about the evidence on which the war in Iraq was based. Max Hastings, a "wet Tory" by his own description, has a comment in today's Guardian in which he argues that it may not even be in Labour's best interests to win reelection in May.

His argument is based on a mix of historical analogy and current political analysis, but boils down to the idea that people eventually get sick of being governed by one party, that the party in power uses up all its good ideas, and that winning a third term can result in a deep dislike for a party rather than a two-term itch. As Hastings sums up

"Our system of parliamentary democracy cannot make provision for limiting party terms. But, just as the Tories today lament that they did not lose the 1992 election before the public grew lastingly sick of them, so some younger Labour MPs may find themselves boring colleagues in the 2010s with their regrets about failing to drop the 2005 one."

I can't say I completely buy the argument. I don't think it's inevitable that a governing party will run out of ways to keep a country moving forward. However, this feeling does rely on the electorate being capable of making a reasoned distinction between the differing ideas of opposing parties and not giving in to political ennui. OK, when I put it that way it's easier to see what he means.

Saturday Morning Physics

2005-04-11T00:13:00.000-04:00

In late 2002 I began a new public lecture series in Syracuse, called Saturday Morning Physics, which is designed to share the ideas and excitement of cutting edge modern physics with people with no previous science education. I was motivated to do this after a visit to the University of Michigan, during which I attended one of their lectures of this type and was stunned with how popular it was.

The Syracuse incarnation is now a regular event, with a growing audience drawn from local high schools and the public in general. I spent Saturday morning running the tenth lecture in our series. The previous nine

Searching for Ripples in Space-time: Fulfilling Einstein's Vision
Modern Cosmology and the Building Blocks of the Universe
The Case of the Missing Antimatter
Black Holes: the One Hour Tour
`Catch a Falling Photon, Put it in Your Pocket.': The Science of Solar Energy
Chaos: Snowfall, Dirty Dishes, and the Paths of Planets
Astrochemistry and Astrobiology: Exploring the Chemical Factories of Interstellar Space
Soft Matter: Geometry and Materials
Physics and Society: from individual Enabling Technologies to Global Crisis Communications

have been quite successful, drawing audiences of between 80 and 150.

Saturday's talk was something a little different, as it was also part of our World Year of Physics celebration. My colleague Peter Saulson, who is the spokesperson of the LIGO Scientific Collaboration and is a wonderful speaker, gave a masterful lecture titled "A Celebration of Einstein's `Miracle Year'". Peter described Einstein's 1905 papers on Brownian motion, on the photoelectric effect and on special relativity, explaining the essential physics, the revolutionary nature of the papers and the lasting impact that these insights have had on physics and technology. If you would like to read an eloquent description of the science and its implications, take a look at Brian Greene's editorial, One Hundred Years of Uncertainty, in Friday's New York Times.

Peter ended the lecture in a novel way by reporting to the audience about how individual Syracuse Physics professors felt that the three 1905 papers influence their research today. He had surveyed most of the faculty and the responses were quite interesting, pointing out the connections to cosmology, condensed matter physics, particle physics and solar energy research.

I was delighted that one of my colleagues chose to comment on Einstein as a model for the public and political roles that she felt scientists should play. Some of the battles to be fought today are the same as those that faced Einstein's generation, but there are some new ones for which we need to organize. An important example in the U.S. right now is the need for scientists to speak out when faith and belief are replacing skepticism and reason as the basis for government policy. Pharyngula has posted the text of Donald Kennedy's wonderful editorial about these issues in the most recent issue of Science. It's quite well written and, although the need for such an editorial deeply depresses me, it is a relief to see an increasing number of high profile scientists, educators and journalists taking on this cause.

Huxley on the Scientific Method

2005-04-10T08:54:00.000-04:00

Yesterday's 3quarksdaily directs readers to a survey, reported in The Guardian, in which 250 scientists were asked, "What is the one thing everyone should learn about science?" The story is a fun read, with some scientists making quite moving and profound statements. Faced with the current assault on science and reason by our administration and its extremist backers, I found reading sensible response after sensible response from my fellow scientists wonderful therapy.

The response from Michael Baum, Emeritus professor of surgery at University College London, refers to one of my favorite quotes from Thomas Henry Huxley ("Darwin's Bulldog"):

"... the great tragedy of Science–the slaying of a beautiful hypothesis by an ugly fact"

What an exquisite turn of phrase.

I'm a Firefighter's Plaything

2005-04-08T12:52:00.000-04:00

This morning I was talking to my wife, Sara Errington, after she arrived home from work, and it occurred to me that I've never mentioned her in this space. So I'm going to come right out with it here - I'm a firefighter's plaything!

Sara and I met when we were both graduate students at Brown University; me in physics (obviously) and Sara in history. Sara knew from early on that she didn't want to be an academic (or, as she puts it - "I can't stand most students") and so, after completing her Ph.D. in early American history, she became a journalist and worked for the Lorain Morning Journal while we lived in Cleveland. After we moved to Syracuse, she landed a nice job with the Post Standard, where she worked for four years. Her analytic, research and writing skills were well suited to journalism and she enjoyed this line of work. However, this isn't the end of her story.

During the first few months at the Post Standard, she was covering an accident scene at which there were volunteer firefighters attending. She commented about what a good time they seemed to be having and they had an application in her hands within a couple of days. She has been a volunteer in DeWitt ever since, rather rapidly becoming a Lieutenant there.

Sara realized relatively quickly that she loved the fire service so much that she wanted to do it full time. After acing the written test two and a half years ago and waiting out a two-year hiring freeze, she was accepted into the Syracuse Fire Academy in August 2004 and graduated in mid-November of that year. She is now one of only three female firefighters in the City of Syracuse (out of 390), and is based at Station 18 in the Valley area.

Needless to say, Sara's path from historian to journalist to firefighter is pretty unusual, even more so because she is a woman and the fire service is still a predominantly male environment. However, her colleagues treat her very well (for the most part) and it is hard to describe how happy she is with her career. I can also report that life's a blast as a firefighter's guy.

Cochlear Implants

2005-04-07T20:49:00.001-04:00

The Physics colloquium here at Syracuse this week was by Ian Shipsey from Purdue University. Ian is a high energy experimentalist who used to be a postdoc at Syracuse well before I came here. His colloquium was an extremely unusual one, titled “Bringing Hearing to the Deaf - Cochlear Implants: A Technical and Personal Account".

In 1989, Ian lost his hearing as a result of intensive antibiotic treatment to protect his immune system after chemotherapy to cure him of Leukemia. He recently received a cochlear implant, which is a remarkable piece of science and technology that can restore neural function to the ear and allowed him to hear for the first time in fifteen years. Between becoming deaf and receiving the cochlear implant Ian and his wife (Daniela Bortoletto, another physicist and a former Syracuse graduate student) had a daughter and, until two years ago, Ian had never heard her voice. Now all that has changed.

Ian discussed in great detail the physics behind the working of the ear and it was truly fascinating. The combination of the passive way in which sound is transferred between the various components of the ear and the active way in which it is amplified through tiny electrochemical motors is a bioengineering marvel. I knew very little of all this and came away significantly educated about the physics and in awe of the tremendous amount of work that has been performed to elucidate the details he discussed.

The second half of Ian's colloquium was about how cochlear implants function. He described their history, the electrical engineering and psychophysics involved, and the clinical evaluation of their performance. He also discussed his personal experience in getting and using his own cochlear implant, as well as making some comments regarding the social implications of implantation.

Ian gave a similar talk at Fermilab lat year, and you can download the slides or watch the video of that talk. I encourage you to do so if you have time; it is a fascinating description of the physics of the human body.

People Love Cosmology

2005-04-06T23:21:00.000-04:00

I finished my Frontiers of Science talk a couple of hours ago. Apart from a few AV hassles at the beginning, things went very well and I had another very positive experience talking to the general public about science. My audience consisted of university students, local people interested in physics and a set of high school students brought to the lecture by their teacher. There were 45 minutes of questions at the end, ranging from general ones about the nature of dark matter and dark energy to one very specific question about Calabi-Yau manifolds. In general, people seemed to get the point about the connections between cosmology and particle physics. I decided not the give them this bad news.

In part of my talk I discussed the contributions that the soon-to-be-euthanized Hubble Space Telescope has made to modern cosmology. Interestingly enough, at the end two women came up to talk to me. They were the mother and grandmother of one of our students and, it turns out, the wife and mother of the launch director of the Hubble mission. They said it was great to finally understand why what he did was useful. Never mind, we appreciate him!

Frontiers of Science

2005-04-05T21:28:00.000-04:00

I hardly have any time for blogging today. Tomorrow evening I'm giving the Frontiers of Science lecture here at Syracuse. This is a popular-level lecture and my title is "Modern Cosmology and the Building Blocks of the Universe". The talk will be some kind of amalgam of an existing public lecture that summarizes much of 20th century cosmology, a second that I gave in May 2004 as the public lecture at the Dark Side of the Universe workshop at the Michigan Center for Theoretical Physics, and some material that I'm still putting together. As you can tell, this is not exactly finished yet (hence the lack of blogging time). On the plus side, I do have an abstract though:

"No two ways about it - the universe is really, really big! If we want to understand it, we need to know about nature on very large scales. On the other hand, I think we'd all agree that atoms and their constituents are extremely small! To understand them requires us to know about nature on very small scales. The challenge of modern cosmology is to use these seemingly different aspects of physics to explain how a young, hot, small universe became the old, cold, huge universe we see today: to understand the physics of the Big Bang. In the first part of this talk, we will tour the major ideas of 20th century cosmology. We will see that a series of remarkable experiments completed over the last decade provide convincing evidence that the universe is roughly 4% ordinary matter (the stuff of the periodic table), 26% dark matter (the nature of which is mostly unknown), and 70% dark energy (the nature of which is almost completely unknown). In the second part, I will try to give a picture of how cosmologists are trying to address these questions, requiring the physics of the large and the physics of the small to work together."

The Ditch Blair Project

2005-04-04T21:40:00.000-04:00

The Guardian is reporting that tomorrow morning Tony Blair will formally ask the Queen to call a general election on May 5. This comes after a Guardian/ICM poll showed Blair's government holding only a slim three-point lead over the Conservatives. This puts me in an incredible bind.

In the U.S., I would have deeply opposed George W. Bush even if he hadn't led us into Iraq, because his social and economic policies are, in my opinion, designed to make the lives of working people in America worse and worse. If I could vote in the U.S., I would be a Democrat, for all their faults.

In Britain, however, I vote Labour, because that party has traditionally been the one whose economic and social policies have been the best for the working class, from which I proudly hail. (You can't imagine the party I'll hold when Margaret Thatcher finally croaks.)

Despite all this, the prospect of re-electing Blair is a difficult one. I cannot understand his stance on Iraq and feel deeply betrayed by his government. It is disproportionately the children of the poor who end up fighting wars and, although they are sometimes necessary, for a Labour government to send our soldiers off to fight on such flimsy evidence is hard to forgive.

I can't imagine ever voting Conservative (unless their primary policies become those of the Labour party), but it is hard to imagine rewarding Blair for his dreadful lack of judgment (and I'm being kind here). I really don't know what I'll do. I might consider voting for a third party, but I don't want to look back and be the British equivalent of a repentant Nader voter.

Doubtless I'll mull this over further in this space as the date nears.

Opening Day

2005-04-03T19:15:00.000-04:00

I have found it quite hard to get into American sports, but when I lived in Cleveland I became hooked on baseball. We lived less than a mile away from Jacobs Field and I went to a lot of games. Two were particularly memorable.

The first was when my friend Dan Akerib (a dark matter experimentalist) and I were lucky enough to watch Cleveland come back from eight runs down, sitting just eight rows behind home plate. Wonderful!

The second was during an 80th birthday fest for Les Foldy, a famous particle physicist and great guy, who has since sadly passed away. Attending the fest were Gerard 't Hooft (Nobel Prize 1999), Frank Wilczek (Nobel Prize 2004), James (BJ) Bjorken and Mark Wise (no slouches either). The owner of the Indians gave his suite to twenty-two of us from Case Western, including these guys, for a whole evening. It's a lot different up there. In particular, I don't ever recall being able to get the attention of the dessert and liqueur cart from the nosebleed section.

Today is opening day, and the Indians aren't playing. However, since the Yankees are (and against my second team, the Red Sox), I can still enjoy rooting against them. The most important thing about all this, from my perspective, is that it's starting to feel like summer in the North East.

Cosmic Acceleration from Topological Defects

2005-04-02T13:39:00.000-05:00

A few days ago I posted a preliminary description of topological defects, as a prelude to a brief discussion of how they can lead to cosmic acceleration. In that post I focused on an analogy between field-theoretic systems and a simple mechanical system consisting of pencils, stood on their ends on a table, and connected to their nearest neighbor pencils by springs. In a field theory, it is (usually) a scalar field that picks out a specific direction in field space, spontaneously breaking the overall symmetry of the theory. In the pencil example, any direction in the plane is a vacuum, but when a pencil picks out just one, it breaks that symmetry (in this case rotational invariance in the plane).

Just as with the pencils, if the space of vacuum states, from which the field chooses, is topologically nontrivial, then the field can pick different vacua in different regions of field space. This can then result in a small region of space in which the field is not in the vacuum and, in fact, takes the value it did before the symmetry broke. We say that this region, the core of the defect, is in the unbroken symmetry phase.

Because the core is not in the vacuum, it is a region of approximately constant energy density, which is rendered metastable by topology. In broad terms, for a lone defect, this means that the core is like a small region of cosmological constant and the rest of space is in the vacuum. For example, for an infinite straight string, the energy-momentum distribution is like having a cosmological constant in the direction along the string.

If defects form during phase transitions as the universe cools, which is what we expect if the relevant field theory has the appropriate topological features, then networks of defects will form. Under certain circumstances, the defect network will frustrate; that is to say that it will form a frozen network, which you can imagine as a mesh-like configuration pervading space. Since the physical orientations of defects are random as one traverses the network, one can average over them to obtain a homogeneous, isotropic distribution of energy density on large scales.

How does this energy density evolve? You might expect that because each defect behaves, in part, like a cosmological constant, this might lead to an overall cosmic acceleration. The actual answer depends on the dimensionality of the defect. In a gauge theory one obtains the following; a system of magnetic monopoles evolves like regular matter; a network of cosmic strings evolves like a fluid with equation of state parameter w=-1/3, which is precisely on the border between decelerating and accelerating cosmologies; and a network of domain walls yields w=-2/3, which would indeed cause cosmic acceleration.

Current measurements of the equation of state of dark energy disfavor an equation of state parameter so far from w=-1. However, it is still possible that a frustrated defect network is part of the cosmic energy budget, and it is fascinating (to me at least) that nonperturbative solutions to particle physics theories can have such a profound effect of the evolution of the universe.

My Grandad

2005-04-01T13:43:00.000-05:00

My Dad just directed me to a web site titled Prisoners of War, which is "a tribute to those men who were imprisoned in Stalag 18A, Wolfsberg, Austria from 1941 to 1945". One of these men was my paternal Grandfather, Peter Trodden. My Dad has posted an account of what happened to my Grandad, which I found incredibly moving and sobering. We all know that war is terrible, but when you're reading about someone you knew and loved, it's worse. My Dad's account begins

"Peter Trodden worked as a butcher and had also boxed as a professional. He lived in Altrincham, Cheshire, although he was born in Bury, Lancashire in 1916. He volunteered at the outbreak of war and became a gunner in the Royal Artillery.

On 15th November 1940 his battalion left Paignton for the ill-fated battle of Crete.

They travelled by way of Liverpool, Freetown, Durban, the Suez Canal and Beni Usef, Cairo where they had three weeks intensive training. Then via Port Said and on to Crete, where they arrived on 30th January 1941. As is well documented, things did not go well and on 15th July 1941 he and many others sailed for Salonika on the Yalova as POWs. ..."

There's a lot more if you follow the link above. This might not be that interesting to anyone outside my family, but who knows.

W on Terri Schiavo

2005-03-31T17:36:00.000-05:00

Terri Schiavo's body finally died this morning; her mind having died many years ago. The President, demonstrating his usual stunning ignorance of scientific evidence, had this to say

"The essence of civilization is that the strong have a duty to protect the weak. In cases where there are serious doubts and questions, the presumption should be in the favor of life."

I find this remarkable for two reasons. First, it is just plainly untrue that there were serious doubts and questions, where by "serious" I mean ones that were not clearly addressed by the respected medical experts who explained patiently that her cerebral cortex had been almost entirely replaced by spinal fluid. Second, where was this opinion when there were serious doubts and questions raised about the evidence used to send us to war in Iraq? How many lives (and their accompanying minds) could have been saved? I guess it only comes out when it serves to stimulate the religious right.

Topological Defects

2005-03-30T19:33:00.000-05:00

Today's cosmology/relativity/particle physics seminar at Syracuse was given by Brandon Carter from the Observatoire de Paris-Meudon. Brandon spoke about the stability properties of the "solid dark matter" model of the accelerating universe, proposed by Bucher and Spergel. The main idea of Bucher and Spergel is that, under certain circumstances, topological defects may lead to an accelerated expansion. I'd like to post about this, and may do so tomorrow. However, as a prelude, I thought I'd better provide a version of what topological defects are.

Topological defects are extended solutions to field theories that can arise when the vacuum structure of the field theory is topologically nontrivial. As a somewhat simple example (and, I admit, a clumsy one, but its the best I can do right now), let us model a field theory by standing many pencils on their ends on a table top, and connecting the pencils to their nearest neighbor pencils by springs. What is the vacuum configuration of these pencils? Obviously, because of gravity, each individual pencil would like to lie down on the table, but doesn't care which direction it is pointing as long as it is lying down. So the vacuum configuration of the theory is all the pencils lying down, facing in the same direction, because if any pencil faces in a direction different from that of its neighbor, then there will be energy bound up in the spring which is stretched between them, which can be reduced by the two pencils aligning. Obviously, there are an infinite number of equivalent vacua, corresponding to all the pencils aligning in any of the possible directions in the plane of the table.

Now suppose that the table is very big (maybe even infinite), and pencils that are very far apart from each other fall down into different vacuum states, because causality doesn't permit information to travel between them so that they can align. You could imagine, in fact, that pencils that trace out a very large circle all fall down pointing outwards in different directions along that circle. All other pencils inside that circle will try to align with the pencil closest to them, in order to reduce the energy in the springs. However, if you think through this for a moment, you'll see that there will always be one pencil, the one at the center, which is equally pulled in all directions and so will remain standing up - now stably. In fact, a few pencils on each side of this one will be partially standing up, because of the spring tension.

These few pencils, and particularly the one at the center, represent what is meant by a topological defect. It is a small region of space, in which the field configuration is out of the vacuum manifold, but which remains metastably in that configuration because the topological properties of the vacua chosen by the field at infinity are nontrivial. I won't harp on about how these topological properties are defined, because it's more technical than the sketch above and won't buy us much clarity here.

In the model system above, the topological defect is point-like - it is just a single point in space. In three spatial dimensions one can have either point-like defects (monopoles), line-like defects (strings) or membrane-like defects (domain walls). Which, if any, of these exist depends on the particular particle physics model one considers. However, there are some generic situations that are important. The most well-known occurs if one has a grand unified theory, which unifies the strong, weak and electromagnetic forces so that they are described by one simple gauge group. In this case, when the group breaks to the standard model of particle physics, as it must, monopoles are inevitably formed. These can be problematic in the context of cosmology, and were one of the original motivations behind the development of the inflationary universe.

Doing Fourier Transforms at Caltech

2005-03-28T17:30:00.000-05:00

I'm in the middle of my trip to Caltech, which I am enjoying very much. Given that I'm discussing physics with people most of the day and then flying out, there isn't much time to post. I just had a nice chat with Mark Wise about the much-discussed Kolb, Matarrese, Notari and Riotto paper. I know Rocky and Toni quite well and am, in general, a big fan of their work. I haven't been able to understand this paper sufficiently well to have an opinion yet (see Sean Carroll's take on this over at Preposterous Universe), although I confess that the result goes against my intuition (wouldn't be the first time a correct result had managed this though).

For some reason, Mark and I tied ourselves in knots trying to compute the particular variance calculated in their paper, but, I am happy to report, we did succeed in doing the Fourier transform correctly at the end. Given the amount of interest in this paper (perhaps because of the press release), I'm going to have to work through it in much more detail and will report here after doing so (hopefully).

Back to Syracuse tonight so that I can teach tomorrow and host our seminar speaker, and my former collaborator, Brandon Carter - the man who coined the phrase "the anthropic principle". Now there's a topic begging to be blogged about.

Travelin' Man

2005-03-27T06:59:00.000-05:00

In a couple of hours I'm headed back to California for a quick visit to Caltech, where I'll be giving the High Energy Physics seminar tomorrow afternoon and then heading back on the red-eye in time to teach on Tuesday. This is a fun talk to deliver since, unlike the usual seminars I am invited to give, the audience here will be a mixed group of experimentalists and theorists. My seminar is titled "Connecting Cosmology and Fundamental Physics" and I'll be talking about a selection of topics. Some, like baryogenesis, I've already made an attempt to explain here at Orange Quark. Others, like dark energy and inflation , I've yet to discuss, but intend to get into before too long. The focus of the talk is the challenges to particle physics posed by cosmological issues and the fascinating possible solutions that theorists are contemplating

The other nice part of my trip is that, before my flight tomorrow evening, I'm having dinner with Marc Kamionkowski and his group. Marc's a smart and talented cosmologist and it'll be both fun and educational to discuss cosmology with him and his students and postdocs.

Barring delays and cancellations I should be spending this afternoon in glorious sunshine (last time I said that it rained for four straight days in San Francisco, but I'm an optimistic guy) sipping a glass of wine and working on my talk. Otherwise, surely there must be a few square meters of O'Hare that I haven't explored twenty times already.

Electroweak Baryogenesis

2005-03-26T19:26:00.000-05:00

In a recent post, I discussed the puzzle posed for cosmologists and particle physicists by the observation of the baryon asymmetry of the universe (BAU) - the fact that the universe is composed almost entirely of matter, with a negligible amount of antimatter. There was quite a bit of interest in this topic expressed in the comments for that post, and I thought it would be fun to go into a little more detail about one popular idea about how the BAU might be generated. Obviously, all my posts won't be as technical as this one, but it seemed like there would be some audience for such a description. If people are interested in even more (some might say excessive) detail, they could read this review article, or this one.

The precise question that concern us is; as the universe cooled from early times, at which one would expect equal amounts of matter and antimatter, to today, what processes, both particle physics and cosmological, were responsible for the generation of the BAU? In 1967, Andrei Sakharov established that any scenario for achieving this must satisfy the following three criteria;

Violation of the baryon number (B) symmetry
Violation of the discrete symmetries C (charge conjugation) and CP (the composition of parity and C)
A departure from thermal equilibrium.

In recent years, perhaps the most widely studied scenario for generating the BAU has been electroweak baryogenesis. In the standard electroweak theory baryon number is an exact global symmetry. However, baryon number is violated at the quantum level through nonperturbative processes - it is an anomalous symmetry. This feature is closely related to the nontrivial vacuum structure of the electroweak theory.

At zero temperature, baryon number violating events are exponentially suppressed (this is most certainly a good thing, since we would like the protons making up our bodies to remain stable). However, at temperatures above or comparable to the critical temperature of the electroweak phase transition, B-violating vacuum transitions may occur frequently due to thermal activation.

Fermions in the electroweak theory are chirally coupled to the gauge fields. In terms of the discrete symmetries of the theory, these chiral couplings result in the electroweak theory being maximally C-violating.
However, the issue of CP-violation is more complex. CP is known not to be an exact symmetry of the weak interactions (this is observed experimentally in the neutral Kaon system). However, the relevant effects are parametrized by a dimensionless constant which is no larger than 10^-20. This appears to be much too small to account for the observed BAU and so it is usual to turn to extensions of the minimal theory. In particular the minimal supersymmetric standard model (MSSM).

The question of the order of the electroweak phase transition is central to electroweak baryogenesis. Since the equilibrium description of particle phenomena is extremely accurate at electroweak temperatures, baryogenesis cannot typically occur at such low scales without the aid of phase transitions. For a continuous transition, the associated departure from equilibrium is insufficient to lead to relevant baryon number production. For a first order transition, quantum tunneling occurs around a critical temperature, and nucleation of bubbles of the true vacuum in the sea of false begins. At a particular temperature below this, bubbles just large enough to grow nucleate. These are termed critical bubbles, and they expand, eventually filling all of space and completing the transition. As the bubble walls pass each point in space there is a significant departure from thermal equilibrium so that, if the phase transition is strongly enough first order, it is possible to satisfy the third Sakharov criterion.

There is a further criterion to be satisfied. As the wall passes a point in space, the Higgs fields evolve rapidly and both CP violation and the departure from equilibrium occur. Afterwards, the point is in the true vacuum, baryogenesis has ended, and baryon number violation is suppressed. Since baryogenesis is now over, it is imperative that baryon number violation be small enough at this temperature in the broken phase, otherwise any baryonic excess generated will be equilibrated to zero. Such an effect is known as washout of the asymmetry and the criterion for this not to happen translates into, among other things, a bound on the mass of the lightest Higgs particle in the theory. In the minimal standard model, current experimental bounds on the Higgs mass imply that this criterion is not satisfied. This is therefore a second reason to turn to extensions of the minimal model.

One important example of a theory beyond the standard model, in which these requirements can be met, is the MSSM. In addition, there are also light stops (the superpartners of the top quark) in the theory, which can help to achieve a strongly first order phase transition. For those of you who care about the numbers, according to recent calculations, baryogenesis is possible if the lightest Higgs particle has a mass less than 120 GeV, and the lightest stop has a mass less than the top quark mass.

What would it take to have confidence that electroweak baryogenesis within a particular SUSY model actually occurred? First, there are some general predictions: if the Higgs is found, the next test will come from the search for the lightest stop, and important supporting evidence will come from CP-violating effects which may be observable in experiments involving B-mesons.

However, to establish a complete model, what are really necessary are precision measurements of the spectrum, masses, couplings and branching ratios to compare with theoretical requirements for a sufficient BAU. Such a convincing case would require both the Large Hadron Collider (LHC) and, ultimately, the International Linear Collider (ILC), in order to establish that this is truly how nature works.

Dark and Twisted Political Cartoons

2005-03-25T11:37:00.000-05:00

The BBC is carrying the story of a Syrian cartoonist, whose work, while not explicitly mentioning any individuals or countries, wickedly lampoons authoritarian regimes. My favorite example is the one I've posted on the right. The artist, Ali Farzat, used to publish a satirical magazine, but that was ultimately banned, and it's an uphill struggle for him to get his cartoons published anywhere.

The BBC story is really about restrictions on the media in Syria and contains some interesting points about the roles that the internet and international satellite TV are playing in getting information through to the populace, despite the restrictions.

However, I mostly just enjoyed the cartoons, which are a lot of (dark) fun. There are a couple of other examples in the story, and you can find a few more in this slide show from the Guardian.

Science Under Attack

2005-03-24T08:02:00.000-05:00

Americans have played a crucial and profound role in much of the scientific and medical progress of the last century. During that time, Americans have won 242 Nobel prizes, more than the combined number won by the next four countries on the list (the United Kingdom, Germany, France and Sweden), according to britannica.com. Obviously, the sheer size of the country is a factor here, but the number is, nevertheless, remarkable. One of the factors behind these impressive achievements is the importance placed on the public funding of science. This dedication to American excellence does not only yield fancy Swedish prizes though. It lies behind the technology and information fields on which an increasing portion of our economy relies; it lies behind the increasing longevity of Americans; it lies behind our quality of life, particularly for the elderly, the infirm and the disabled; it lies behind our partial ability to predict and protect ourselves from natural disasters; it lies behind our national security, and, like it or not, it lies behind the dominance of our military. A comprehensive list would be much longer than this.

Equally important, particularly to those of us who devote our working lives to science, is that progress in science adds to our knowledge of our world, of our universe and of what it means to be humans exploring them. To paraphrase Robert Wilson, first director of what would become the Fermi National Accelerator Laboratory, when asked by Congress whether the laboratory would contribute to the national defense; the primary contribution of science is not to the defense of the nation but rather to what makes the nation worth defending.

These days, the tremendous American legacy in science and medicine is under attack and faces a crisis that, if not overcome, will result in us ceding leadership in these fields to other nations for generations to come. Decreased funding for basic science, the misguided direction of NASA, the suppression of scientific information involving contraception, abortion and sexual practices, and the denial of evolution and cosmology are but a fraction of the obstacles to progress that have sprung up in recent years.

This attack on the leading role the United States plays in science and medicine is happening because our value systems are being hijacked by a small number of well-organized and well-funded extremists on the far religious right. If you have a child and you want that child to grow up and succeed in the modern world, you need to take action now to prevent the education she so badly needs from being corrupted.

As Frank Rich, writing in the New York Times, describes, as part of a much longer article that I encourage you to read:

"...polls consistently show that at most a fifth of the country subscribes to the religious views of those in the Republican base whom even George Will, speaking last Sunday on ABC's "This Week," acknowledged may be considered "extremists." In that famous Election Day exit poll, "moral values" voters amounted to only 22 percent. Similarly, an ABC News survey last weekend found that only 27 percent of Americans thought it was "appropriate" for Congress to "get involved" in the Schiavo case and only 16 percent said it would want to be kept alive in her condition. But a majority of American colonists didn't believe in witches during the Salem trials either - any more than the Taliban reflected the views of a majority of Afghans. At a certain point - and we seem to be at that point - fear takes over, allowing a mob to bully the majority over the short term. (Of course, if you believe the end is near, there is no long term.)

That bullying, stoked by politicians in power, has become omnipresent, leading television stations to practice self-censorship and high school teachers to avoid mentioning "the E word," evolution, in their classrooms, lest they arouse fundamentalist rancor. The president is on record as saying that the jury is still out on evolution, so perhaps it's no surprise that The Los Angeles Times has uncovered a three-year-old "religious rights" unit in the Justice Department that investigated a biology professor at Texas Tech because he refused to write letters of recommendation for students who do not accept evolution as "the central, unifying principle of biology." Cornelia Dean of The New York Times broke the story last weekend that some Imax theaters, even those in science centers, are now refusing to show documentaries like "Galápagos" or "Volcanoes of the Deep Sea" because their references to Darwin and the Big Bang theory might antagonize some audiences. Soon such films will disappear along with biology textbooks that don't give equal time to creationism."

This is a crisis for all of us, and every day we ignore it and hope it will go away, more ground is lost in the battle for facts against fiction. This is not about science versus religion – that is a different story. Indeed, when our elected officials replace scientific facts and analysis by theology, they not only devalue science, but also devalue religion, by using it to cast doubt on the beauty and wonder of the natural world. Rather, this is about the right of Americans to have free access to the wealth of well-established facts about this world that their hard-earned dollars have helped to discover. The scientific legacy of great American scientists belongs to all Americans and we should be outraged about any attempts to suppress it, to corrupt it or to undermine its future.

Relativity, Cosmology and Undergraduate Imaginations

2005-03-23T17:30:00.000-05:00

I’ve spent a reasonable fraction of today meeting with students from my undergraduate relativity and cosmology class. The class is aimed at students with very little physics background, but with some mathematics, including two semesters of calculus. I inherited the class from my former colleague Don Marolf, who is now a Professor at U.C. Santa Barbara. Don had done a wonderful job with this course, developing a substantial reader with huge amounts of information about special and general relativity, and a small amount of cosmology.

This is my first year teaching the course. I’ve changed it around somewhat, removing some of the relativity in order to get to the black hole solution and its features by this week, so that I can then spend half the semester on cosmology. This doesn’t mean I didn’t love it the way Don had it, just that my personal interests lie in slightly different areas.

An integral part of the course are the student projects. Naturally, these must concern a topic related to the course material. However, beyond that there aren't many guidelines about what the project actually is allowed to be. The students in this class are a lot of fun to teach - smart and full of great questions that fill up the class time before I know it. Today's meetings were to discuss project ideas, and I must say it was a blast. Here are some examples of what they want to do:

A popular-style article about time travel
A computer code to calculate and describe how particles move around a black hole
A magazine article on relativity in more than four space-time dimensions
A review article on experimental tests of the inverse square law of gravity
A web site to teach high-school students about gravitational waves
A computer game in which rocket ships race and one can observe the race from different reference frames
An article about the evidence for an accelerating universe
A magazine-style article about experimental tests of general relativity
...

The list goes on and on. The computer game is particularly inventive. The students not only have to complete these projects and turn them in; they also have to present them to the whole class. Its a lot of work, but they're clearly up to it.

I'm having a wonderful time watching them come to grips with material that is so fascinating to me personally. I truly think that most people are fascinated by science, but don't have enough easy opportunities to learn more about it. At Syracuse our Saturday Morning Physics Lecture Series is one attempt to give people such an opportunity. I'm planning to discuss this and a number of other outreach activities in a post in a few weeks time, after several upcoming and related events are completed.

Preserving Life at (almost) Any Cost

2005-03-22T08:20:00.000-05:00

Yesterday the US Congress acted quickly and decisively to pass legislation to force reinsertion of the feeding tube into Terri Schiavo, the tragic Florida woman who is in a persistent vegetative state. The President, who returned early (yes, that's right, you didn't misread it) from Texas to sign the bill, said that "...it is wisest to always err on the side of life,". That Congress and the President were willing to override the established wishes of Ms. Schiavo and of her husband, and were willing to ignore separation of powers to take this extraordinary step, speaks volumes about their commitment to saving human life whenever possible.

Also in the news today, a Minnesota teen killed his grandparents, 6 students and a teacher before killing himself. His rampage used multiple weapons, including a shotgun and two pistols. I wonder what kind of rapid, special, sanctity-of-life preserving legislation could make it more difficult for this to happen again (and again and again)? It would, of course, have to be passed over the established wishes of those closest to the weapons.

In case you didn't catch the sarcasm in the opening paragraph (I was laying it on pretty thick though), I am dismayed to see the US Congress getting involved in this kind of matter. In my country of birth, England, government debates only weighty issues of national importance. For example, this morning I saw an interview with a Labour MP (one of those that used to devote their time to making life better for the working class) who was discussing his outrage that Camilla Parker Bowles might become Queen after she marries Prince Charles and after he becomes King. Note to the British government on behalf of my family who still live there: please put the antics of the anachronistic products of centuries of inbreeding further down your list than decent healthcare, education and law and order.

Matters of Antimatter

2005-03-22T00:04:00.000-05:00

As promised in my last post, I thought I’d spend a bit of time discussing the source of the fuss that cosmologists make over matter and antimatter.

Antimatter is just like ordinary matter in every way, except that every quantity you can think of (apart from mass and spin), is reversed. As an example, the electron is a particle with a specific mass and carrying a specific amount of negative electric charge. The antiparticle of the electron is a positron, which has the identical mass to an electron, but precisely the opposite charge. The thing about particles and their antiparticles is that, if one puts them together, the net value of any quantity (called a quantum number by physicists) carried by the pair of them is zero. Therefore, a particle and an antiparticle together are merely mass which, thanks to Einstein’s E=mc², can be converted entirely into energy. As a result of this, when matter and antimatter come together, they annihilate, producing energy in the form of light (photons).

We know so much about antimatter for two reasons. The first is that it is a natural part of quantum field theories, which we use to describe matter, and which are among the best-tested theories in all of science. The second is that we can make and investigate antimatter in large amounts. For example, the purpose of the Fermi National Accelerator Laboratory near Chicago is to make vast numbers of antiprotons to study how they annihilate with protons.

Antimatter is important in cosmology because of the extreme temperatures and densities of the early universe, as described in a previous post. One consequence of such an extreme environment is that there is so much energy around that any kind of matter (including antimatter) can be created. Therefore, in the early universe, one expects there to have been equal amounts of both matter and antimatter and then, as the universe cooled, for these particles to find each other, annihilate, and leave our present universe with very little matter around (and an equally small amount of antimatter).
This is clearly at odds with what we observe in the universe, where we have relatively large amounts of matter and essentially no evidence of primordial antimatter. In fact, this asymmetry between matter and antimatter can be made quantitative (for baryons such as protons and neutrons) through observations of the abundances of light elements in the universe (Big Bang Nucleosynthesis) and also from the pattern of anisotropies in the cosmic microwave background radiation (CMB). At some point in the future I will post about both these topics, which are fascinating in their own rights. However, for now, suffice it to say that there is clear evidence that the universe is composed of matter, with negligible antimatter.

This all constitutes a puzzle for cosmologists. How did the universe evolve from early times, in which there were equal numbers of baryons and antibaryons, to the present universe, in which there is a precisely measured baryon asymmetry of the universe (BAU)?

Potential solutions to this puzzle provide a wonderful example of the interplay between particle physics and cosmology. A beautiful feature of many theories beyond the standard model of particle physics is that, when considered in the context of the expanding universe, they automatically contain such a dynamical mechanism that can, in principle, explain the origin of the BAU. The generation of the BAU through one of these mechanisms is what is known as baryogenesis. This isn’t enough of course; we don’t yet know which, if any, of these theories might be the right one. However, upcoming experiments, such as those at the Large Hadron Collider (LHC), provide the exciting possibility of either ruling out some of them or providing significant evidence for one of them. Since I’ve worked a lot on such ideas during my career, this is a topic close to my heart.

Wine Snobs Rock

2005-03-21T01:31:00.000-05:00

I just returned from the LCWS2005 conference banquet, which was combined with the conference outing, and took place aboard a cruise ship around the Bay. We've had quite poor weather while I've been out here on this trip. It even poured down with rain while we were on the bus to San Francisco, and Wim de Boer and I made good use of the time discussing some details of electroweak baryogenesis. This is a particularly interesting approach to understanding why the observable universe is composed almost entirely of matter, with negligible amounts of antimatter. I've worked on this a lot in my career and will devote a whole post to this fascinating topic some time soon.

Luckily, the weather cleared up beautifully for the cruise and the views were spectacular. We took a slow pass past Alcatraz island before heading under both the Golden Gate and Bay bridges. As night fell the sky cleared nicely and revealed a beautiful view of the city as we came back to the pier.

All this was wonderful, but, if forced to, I'd trade good views at a banquet for fine food and wine any time. Fortunately, I didn't have to make that choice. The food was perfectly fine banquet food. However, the wine was something else. I was lucky enough to sit with my friends JoAnne Hewett and Tom Rizzo at dinner. These people are serious wine connoisseurs (did I accidentally write "snobs" in the title of this?) and were kind enough to bring a few selected bottles to share with their table-mates. Believe me, these were well worth the $15 a bottle corking fee the wait staff charged us when they saw what was going on. Many thanks to JoAnne and Tom for this crucial component of a lovely evening.

Tomorrow I head back to Syracuse so that I'm back in time to teach on Tuesday. The conference is over a day later. Wish me the luck that one needs to fly from A to B without significant delays these days.

A Signal of Dark Matter Annihilation?

2005-03-20T01:26:00.000-05:00

This afternoon (Saturday for me here in California, even though the blog will register this as a Sunday post) I chaired the first session of talks on the connections between cosmology and the International Linear Collider. The talks were all excellent, but I particularly enjoyed the one delivered by Wim de Boer, from the University of Karlsruhe in Germany.

Wim was concerned with data from the Energetic Gamma Ray Experiment Telescope (EGRET) on the Compton Gamma Ray Observatory. This experiment discovered an excess of diffuse gamma rays in all directions on the sky, which has puzzled physicists for a while now. Wim's claim is that this observation is well explained by the hypothesis that the gamma rays arise from the annihilations of dark matter particles with each other. Working with this hypothesis, Wim and collaborators were able to reconstruct the distribution of dark matter in the galaxy required to yield the observed gamma ray excess. This is a very tempting idea and, if verified, it would be a wonderful piece of evidence for dark matter.

There is more to this story though. The predicted distribution contains a ring of excess dark matter in the galaxy. What is fascinating is that two years ago the Sloan Digital Sky Survey (SDSS) announced the discovery of a corresponding ring of stars in the galaxy, thought to be left over from the collision of a smaller, dwarf galaxy with our galaxy billions of years ago. It is natural that there would be an associated ring of dark matter in the same location. Together these two pieces of data may therefore be our first tantalizing hint of dark matter annihilation.

(Wim went further, considering a particular dark matter candidate - the neutralino in minimal supergravity (mSUGRA) models. This part was more technical and model-specific, and while it was also fascinating, I won't go into the details here.)

The last talk of the day was a colloquium on collider-cosmology connections. A year ago, at the LCWS2004 meeting in Paris, I gave this talk. This year Jonathan Feng delivered it and did a truly masterful job, providing material at a variety of levels to match the varied levels of expertise in the audience. These connections are important to particle physics and to cosmology and Jonathan described them perfectly.

All in all a great day of physics.

The Future of NASA

2005-03-19T02:27:00.000-05:00

We physicists are a pretty inclusive bunch. We love to point out that a physics training makes one ideal for many other careers in which one can make a real contribution to society, and we love to claim people who've demonstrated this successfully as our own. We do this partly because its actually true, partly because we want more physics majors, and partly because we think a scientifically literate society will benefit everyone. To give just one example, physicists will often point out that Congressman Rush Holt (D - NJ) is a physicist. His economic development plan for central New Jersey is even called Einstein's Alley. (The other physicist-Congressman is Vern Ehlers (R - MI)). Sometimes, however, it's best for us to hold off until we see how things work out.

This from the always-insightful Bob Park's What's New column

THE VISION: AEROSPACE ENGINEER PICKED TO LEAD NASA TO MARS.
Described in media stories as a Johns Hopkins physicist, Michael D. Griffin is at the Applied Physics Lab, a government contract lab far from the campus, and although he has a B.A. in physics, his Ph.D. is in Aerospace Engineering from the Univ. of Maryland. During the Reagan years he was Deputy for Technology of SDI (Star Wars), which managed to squander $30B on mythical weapons. Eighteen months ago, Griffin testified before the House Science Committee on "The Future of Human Space Flight". ...

NASA has the experience and potential to do wonderful things for science; given the right direction and a leader who can make it happen. In my opinion one component needs to be a commitment to robotic missions for scientific exploration, which have been a remarkable success so far, and lack the cost, danger and technological constraints of manned missions. The second requirement is a drive to investigate the universe with great observatories, with new probes of inflation, of black holes and of the nature of the dark energy, and to have the vision to go further. Like many other physicists, I'll be watching carefully, with fingers crossed.

Putting the International in "International Linear Collider"

2005-03-18T12:38:00.000-05:00

I'm sitting in the conference hall for the first day of sessions at the International Linear Collider Workshop (LCWS2005) at Stanford University. A large part of the first day's presentations are concerned with collaborative, political and management issues associated with this effort. For the large collaborations that are common in experimental particle physics, such issues are central to the project's success, although they remain largely invisible to anyone outside the collaboration. For the ILC this is even more true and, although I'm itching to get on to the physics part of the conference, I do find it somewhat fascinating to see how the cogs and wheels of a project like this are arranged to get the job done.

Perhaps the most important part of the ILC effort is its international nature. An incredibly rewarding part of being a physicist is that one is constantly engaged in intellectual endeavours with colleagues from across the planet. For a practicing physicist this is as natural as breathing and essential to making progress in our increasingly complex field. As an example, off the top of my head, during my career I've written papers with physicists from Albania, Algeria, America, Brazil, Canada, Croatia, England, Finland, Germany, Greece, Hong Kong, India, Italy, Romania, Russia, Spain and Switzerland (and I guarantee you I'm forgetting some).

Translating this natural international collaboration on intellectual topics into the political, financial and technological areas required to get the ILC to work is another challenge. To be successful one requires an ironclad physics case for the project, and coherent scientific and organizational messages from the physics community as a whole (not just high-energy physicists) for governments and the general public alike. Without these, the obstacles to a successful ILC may be insurmountable. People here seem very optimistic, but then again you'd expect them to be. I'll try to provide updates to this story at various points in the future, as things progress.