Holiday Links

A random collection of links, on the whole not having anything to do with the holidays:

A Stanford Physics Student in Berkeley is now An American Physics Student in England, and reports from the DAMTP Christmas party, where people were supposed to be wearing “Sci-Fi” costumes, that one physicist came in a black t-shirt with the following printed on the front:

The Anthropic Landscape of String Theory

Leonard Susskind. hep-th/0302019

As far as I can tell, of string theory papers written during the last four years, this is the second most heavily cited (the first is the KKLT one that inspired it). How dare these English people act as if this is some sort of joke?

Raymond Streater’s Lost Causes web-site has always been a wonderful source of anecdotes and opinions. He has a new book coming out any day now from Springer entitled Lost Causes in and Beyond Physics which I’ve just ordered and am looking forward to reading. Streater’s web-site also includes a pretty hilarious commentary on Lubos Motl’s typically absurd review of one of Streater’s earlier books, the deservedly famous PCT, Spin and Statistics and All That, written with Arthur Wightman. I had never realized I was in such good company.

From Streater’s web-site I also found a link to an interesting talk by Guralnick on some of the history he was involved in of work on symmetry breaking in QFT during the sixties which ultimately led to the Glashow-Weinberg-Salam model and what is now known as the Higgs mechanism. The talk tells how leading physicists discouraged work on these ideas as “junk” that wouldn’t lead anywhere and would ensure that one couldn’t get a job. During these years the dominant opinion was that S-matrix theory was the route to future progress, with QFT a dead-end.

Back when I was a physics graduate student I remember every so often picking up a copy of the journal Foundations of Physics and flipping through it, trying to read some of the articles. From what I remember, at the time it struck me as a semi-crackpot phenomenon, mixing a few serious attempts at thinking about foundations with large heaps of nonsense. It seemed clear to me then that serious theorists worked on very different things, trying to understand gauge theories and the Standard Model. A friend of mine who was also a graduate student back in those days recently told me that now the current mainstream literature strikes him as much like that found in the old days in journals like Foundations. I don’t know what this means for physics, but Springer recently announced that Gerard ‘t Hooft (one of the main creators of gauge theory) is taking over as editor-in-chief of the journal. Maybe in times like ours in which there is no experimental guidance, work on foundations should get new emphasis (I think this is one of the points in Lee Smolin’s recent book).

If one wants an overview of recent developments in the interaction of math and physics, one could do a lot worse than read the proposal from various mathematicians and physicists in the Netherlands entitled The Fellowship of Geometry and Quantum Theory (via Klaas Landsman’s web-site).

John Baez’s student Derek Wise has a well-written paper about Cartan connections, and John provides some commentary in his latest This Week’s Finds in Mathematical Physics. I’ve always been fascinated by Cartan connections, since they provide a framework linking very general ideas about geometry with Lie groups. As John notes, they provide a joint generalization of the Riemannian and Kleinian points of view about geometry. They also seem to provide a natural mathematical framework for thinking about the relation between GR and gauge theory. Besides the references given by Wise, one should also note that Kobayshi-Nomizu, the standard reference text among mathematicians on geometry from the point of view of connections, is very much inspired by the idea of a Cartan connection. It seems likely to me that if we ever figure out how to properly understand geometrically how to unify gravity and the standard model, these ideas will be part of the story (although much else will also be required, including an understanding of the role of spinors, and of the geometry behind quantization).

Finally, for comic relief, Kris Krogh pointed me to a talk by Michael Berry from a few years ago, where he describes his experience back in 1985 at CalTech when he was working on quantum physics and zeta-functions, and met up with some of the local string theorists:

I met one of them, who asked what I was working on. When I told him, he fixed me with a pitying stare. “Yes, we have zeta functions throughout string theory. I expect the Riemann hypothesis will be proved in a few months, as a baby example of string theory.”

Update: Several people have pointed out that the Susskind t-shirt or the report about it contain a typo. The correct reference is hep-th/0302219

Update: There’s an interview with me posted on Scienceline, the web-site of the NYU Science, Health and Environmental Reporting Program, with the title Stringing Up String Theory.

Update: Yet another interview, this one with Lee Smolin at IEEE Spectrum on-line, called Thread-bare Theories.

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Scott Aaronson For Sale

Scott Aaronson has adopted a sensible attitude towards the controversy over string theory, announcing in a new posting entitled Mercenary in the String Wars that his allegiances in this “War” are for sale to the highest bidder. I encourage all my extremely wealthy financial backers to take him up on this.

He seems to have reached this decision after enjoying an all-expenses-paid vacation in the Bay Area courtesy of the Stanford string theorists, despite having a great deal of sympathy for the criticisms being made of string theory. While there, he gave a talk for which he makes his notes available, on the topic of Computational Complexity and the Anthropic Principle. It’s quite entertaining, although the fact that anyone is seriously debating the kind of issues Scott discusses is a good indication of how far off the rails string theory has gone.

Scott seems surprised to discover that, in private discussion, string theorists are far more reasonable than he expected from their writings, from the behavior of string theory bloggers like Lubos, and from his conversations with Greg Kuperberg, who is convinced that string theory critics are “intellectually non-serious” (I forgot to mention in my last posting that Kuperberg was someone else I had in mind when quoted in 02138). His experience agrees with my own, that in private conversation I find that most string theorists and I agree much more than one would guess. In such a context I’ve just about always found them more than willing to admit that the current situation of string theory is disturbing, progress has ground to nearly a halt, and that the whole landscape business is extremely problematic. That these attitudes are not well reflected in the public utterances of string theorists I think is due to several factors. Given the problems facing the theory, many find it best to just avoid being quoted publicly, and those who do talk to the press feel that their field is to some extent under unfair attack in the media and they should make their best effort to defend it. Those who spend their time vigorously defending string theory as a healthy research program, attacking its critics on blogs and elsewhere, often represent only a tail in the statistical distribution of views and behaviors of the string theory community.

I also suspect that one reason Scott found the Stanford string theorists behaving more reasonably than he would have guessed is that the last year or so has not been kind to their early hopes that statistical calculations would allow some sort of real predictions to emerge from the anthropic landscape. It has become increasingly clear that this kind of idea just can’t work, for reasons that have been extensively discussed here.

I predict a lively discussion in the comment section over at Scott’s blog, and encourage people to use that venue. Already John Preskill has weighed in with what he thinks is an unintentional double entendre about Susskind: “When I listen to Lenny Susskind, I really believe that information can come out of a black hole.”

Update: Scott is pretty funny, but I have to admit that Lubos is completely hilarious.

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02138

There’s a new magazine aimed at Harvard alums, named 02138 (after the local zip-code), and its second issue has just appeared. Personally I’ve never quite understood the phenomenon of people who retain a lifelong fascination with the fact that they attended Harvard, but it seems that there are a lot of them, and the magazine is partly aimed at them or at anyone with an interest in the place or its alumni. The university already has an alumni magazine that it sponsors, but 02138 appears to intend to provide something edgier and not so much along the lines of promotional material.

This latest issue contains an article about the string controversy, written by John Sedgwick and with a focus on the Harvard angle, including me, fellow Harvard grad Brian Greene, and current Harvard faculty member Lubos Motl. The piece is called Unstrung Heroes, and for the full thing I guess you’ll have to subscribe to the magazine. I fear that Sedgwick has done an excellent job of accurately putting together the most outrageous statements that he could find on this topic, including some things I told him when he came down to New York a couple months ago. He also got some interesting quotes from quite a few physicists about the current state of string theory. These included Glashow, who “said he considers a big book like Woit’s long overdue, because string theory has gone exactly as we imagined. If anything, he adds, it’s even worse than it was.” Weinberg is quoted as saying:

The critics are right. We have no single prediction of string theory that is verified by observation. Even worse, we don’t know how to use string theory to make predictions. Even worse than that, we don’t really know what string theory is.

Cumrun Vafa “calls string theory the major leagues in the field of quantum gravity. As for other theoretical pursuits, he derides them as little efforts here and there.” Barton Zwiebach promotes string theory as possibly being able to “see the origin of the universe, and the very meaning of how space and time are born and what they are.” Michael Peskin claims that we might discover a universe that existed before time as we know it began, while noting “But there is a big debate as to whether this idea makes any sense.”

Sedgwick tells the story of Lubos Motl’s reference to me as the “black crackpot”, and Lee Smolin as the “blue crackpot” (because of the colors of the covers of our books), and his discussion of the desirability of my death. Lubos has evidently been told he’s not supposed to say things like that anymore, and responded to a request for an interview with “I don’t enjoy elementary human rights right now.” There’s a quote which I think originated as a comment on my blog to the effect that Lubos has done for the image of string theory “what the movie Deliverance did for canoeing holidays.”

Perhaps the most outrageous quote is an accurate one from me characterizing some of my experiences criticizing string theory from a position outside the field’s standard rigid hierarchy as being analogous to what happens when one messes with the dominance hierarchy of a chimpanzee troupe. This leads to a lot of strange behavior, flinging of shit, showing of behinds, and all sorts of bizarre behavior. In order to avoid offending people I wasn’t referring to, I should explain that I had in mind specifically some of my experiences when first starting this blog, see in particular the comment section of this posting.

It’s a bit embarassing that I’m made out to in some degree be the hero of this piece, the oppressed underdog that the author tries to set up in contrast to overlord Brian Greene. Sedgwick sees the story of how string theory dominates an academic field despite very limited achievements as quite analogous to the phenomenon he had personal experience with of how “theory” came to dominate the humanities in academia. I think there is something to the analogy, with both kinds of “theorists” starting out as an insurgent minority needing a certain amount of fanaticism to survive and expand their influence. Both groups revel in the complexity and obscurity of their work, convinced that those who disagree with them are stuck in the past or just too dumb to appreciate the great achievements of the difficult ideas involved in the two kinds of “theory”.

Chris W. has pointed me to a site that brings together the two sorts of “theory”. It’s called Scriblerus Press, is run by Sean Miller, who has a blog and is working on a PhD thesis in English on the topic of “the cultural currency of string theory.” Scriblerus is sponsoring and now looking for contributions to an anthology of short creative works that deal with string theory in one way or another.

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Yet More Links

The January Notices of the AMS is out. Two quite interesting articles, one of which is an interview with my colleague Joan Birman. She just recently officially retired, but, at the age of 79 is still very active in research and a major presence in the department, an example to us all. The second is an article by Anatoly Vershik about the Clay Millenium Prizes. Vershik argues that these million dollar prizes are not good for mathematics, and that the story of the proof of the Poincare conjecture shows why. Top mathematicians who think they have a chance of solving one of the Clay problems are going to work on them whether or not the prize exists (the money certainly didn’t motivate Perelman). The prizes give the public a deformed view of what is important about mathematics and encourage unseemly squabbling about how “credit” for a solution will be assigned. Vershik writes:

In my opinion, all this clamor and fuss show that this method of promoting mathematics is warped and unacceptable, it does not popularize mathematics as a science, on the contrary, it only bewilders the public and leads to unhealthy interest.

There’s an excellent article about James Clerk Maxwell in the December Physics World. It’s the 175th anniversary of Maxwell’s birth this year. He lived only to age 48, dying in 1879. The author of the article speculates that “Had he not died so young, Maxwell would almost certainly have developed special relativity a decade or more before Einstein.”

For an update on the US federal budget situation for science, see this AAAS web-page. As far as I can tell, the situation is that (as often happens) the Congress has not yet passed FY2007 appropriations for most of the government, including the DOE and NSF, even though we’re now more than a couple months into the fiscal year. As a result, these agencies are operating under a continuing resolution, without access to the increased funds that were supposed to flow because of the “American Competitiveness Initiative”. The new Congress will have to deal with this after it convenes in January, and news reports I heard today said that Congressional leaders were considering not producing new appropriations bills but running the government on a continuing resolution for the rest of FY2007. Unclear to me what this means for science funding, but it doesn’t sound good. Over the next few years, if the new Democratic Congress makes a serious effort to bring the US federal budget deficit under control, science funding may be under pressure.

At the Scientific American blog, J R Minkel has a story called Comic Books Looove String Theory, about developments in the Ex Machina comic, which is about “a retired semi-super hero turned Mayor of New York City who can control machines with his mind.” In issue 10 a lunatic starts ranting

It’s not about the branes, it’s about the bulk. You were supposed to tell people… Witten is close, but we’re closer.

Minkel doesn’t mention the recent string theory themes in Zippy the Pinhead.

Witten’s new paper with Gukov mentioned here is now available. It is about 160 pages long and generalizes the earlier Kapustin-Witten paper to the ramified case. This involves constructing “surface operators” in the 4d gauge theory, operators attached to surfaces in much the same way ‘t Hooft operators are attached to curves. Unfortunately it doesn’t discuss connections to Khovanov homology that Gukov described in his Strings 2006 talk “Surface Operators in Gauge Theory and Categorification” (I’d provide a link, but the Strings 2006 site seems to be down). The authors also note that Frenkel and Gaitsgory have a “unified approach” to this ramified case, but that “Unfortunately, we make contact here neither with the use of conformal field theory nor with this unified statement. We hope, of course, to eventually understand more.” So, there’s lots more to do…

If you want to get an idea of what it costs to run a theoretical physics center, check out the report of the Michigan Center for Theoretical Physics. The interim director of the MCTP is Gordon Kane, and they will be hosting a symposium next month to celebrate his 70th birthday.

Over at Cosmic Variance, there’s a discussion of the new Martin Scorsese film String Kings, which features “a scene showing work on an extension of the New Jersey turnpike, involving string henchmen (disguised with hard hats and overalls) a large cement truck and Peter Woit.” I guess this doesn’t seem like such a great plot idea to me for some reason. Personally I’ve been thinking that the whole recent controversy over string theory would make a great comic novel. The thing to do is to somehow get David Lodge interested…

Update: The Strings 2006 site is back up, and the Gukov talk mentioned is here.

Update: More about the FY 2007 science budget situation from Science and from FYI.

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Polchinski Review at American Scientist and Cosmic Variance

This month’s American Scientist has a review entitled All Strung Out? of The Trouble With Physics and Not Even Wrong by prominent string theorist Joe Polchinski, and he has posted a slightly edited version of the review with some explanatory footnotes at Cosmic Variance. I assume there will be a lot of discussion of it over there, perhaps with Polchinski participating, so, even though I wanted to write some sort of response here, I’ll leave comments off and encourage people to discuss this over at CV.

First of all I should say that I was quite pleased to see Polchinski’s review. While I disagree with much of it, it’s a serious and reasonable response to the two books, the kind of response I was hoping that they would get, opening the possibility of a fruitful discussion. Unless I’ve missed something, the only review by a string theorist to appear in a publication so far has been Susskind’s almost purely ad hominem one in the Times Higher Education Supplement. There also are two other (not published in conventional media) reviews by string theorists that I know of, a serious one by Aaron Bergman, and a nutty one by Lubos Motl that Princeton University Press paid him to write for some mysterious reason. I’ve heard that several publications have had a hard time finding a string theorist willing to write a review of the books, which I guess is not too surprising. It’s not obviously a rewarding task to involve oneself in a controversy that has become highly contentious, and where some of the main points at issue involve very real and serious problems with the research program one has chosen to pursue.

Much of Polchinski’s review refers specifically to Smolin’s arguments; some of it deals with the endless debate over “background independence”, and the “emergent” nature of space-time in string theory vs. loop quantum gravity. I’ll leave that argument to others.

Polchinski notes that I make an important point out of the lack of a non-perturbative formulation of string theory and criticizes this, referring to the existence of non-perturbative definitions based on dualities in certain special backgrounds. The most well-known example of this is AdS/CFT, where it appears that one can simply define string theory in terms of the dual QFT. This gives a string theory with the wrong number of large space-time dimensions (5), and with all sorts of unphysical properties (e.g. exact supersymmetry). If it really works, you’ve got a precisely well-defined string theory, but one that has a low-energy limit completely different than the standard model in 4d that we want. This kind of string theory is well-worth investigating since it may be a useful tool in better understanding QCD, but it just does not and can not give the standard model. The claim of my book is not that string theories are not interesting or sometimes useful, just that they have failed in the main use for which they are being sold, as a unified theory of particle physics and gravity.

The lack of any progress towards this goal of a unified theory over the past 32 years (counting from the first proposal to use strings to do unification back in 1974) has led string theorists to come up with various dubious historical analogies to justify claiming that 32 years is not an unusual amount of time to investigate a theory and see if it is going to work. In this case Polchinski argues that it took about 50 years to get from the first formulation of QED to a potentially rigorous non-perturbative version of the theory (using lattice gauge theory). The problem with this analogy is of course that in QED non-perturbative effects are pretty much irrelevant, with perturbation theory describing precisely the physics you want to describe and can measure, whereas with string theory the perturbative theory doesn’t connect to the real world. When QED was first written down as a perturbative theory, the first-order terms agreed precisely with experimental results, and if anything like this were true of string theory, we wouldn’t be having this discussion. For the one theory where non-perturbative effects are important, QCD, the time lag between when people figured out what the right theory was, and when its non-perturbative formulation was written down, was just a few months (Wilson was lecturing on lattice gauge theory in the summer of 1973, having taken up the problem earlier in the year after the discovery of asymptotic freedom).

Polchinski agrees that the key problem for string theory is its inability to come up with predictions about physics at observable energies. He attributes this simply to the fact that the Planck energy is so large, but I think this is misleading. The source of the problem is not really difficulties in extrapolating from the Planck scale down to low energy, but in not even knowing what the theory at the Planck scale is supposed to be (back to that problem about non-perturbative string theory…).

Weinberg’s anthropic argument for the size of the cosmological constant is described by Polchinski as a possible “prediction” of string theory, and he recommends Susskind’s book as a good description of the latest views of string theorists. I’ve been far too rude to Polchinski in the past in expressing my views about this “anthropic landscape” philosophy, so I won’t go on about it here. He neglects to mention in his review that many of his most prominent colleagues in the string theory community are probably closer in their views on this subject to mine and Smolin’s than to his, and that our books are the only ones I know of that explain the extremely serious problems with the landscape philosophy.

Recently string theorists have taken to pointing to attempts to use AdS/CFT to say something about heavy-ion physics as a major success of string theory, and Polchinski also does this. I’m no expert on this subject, but those who are like Larry McLerran have recently been extremely publicly critical of claims like the one here that “Physicists have found that some of the properties of this plasma are better modeled (via duality) as a tiny black hole in a space with extra dimensions than as the predicted clump of elementary particles in the usual four dimensions of spacetime.” My impression is that many experts in this subject would take strong exception to the “better” in Polchinski’s claim.

Finally, about the “sociological” issues, Polchinski disagrees about their importance, believing they are less important than scientific judgments, but I’m pleased to see that he does to some extent acknowledge that there’s a serious question being raised that deserves discussion in the theoretical physics community: “This convergence on an unproven idea is remarkable. Again, it is worth taking a step back and reflecting on whether the net result is the best way to move science forward, and in particular whether young scientists are sufficiently encouraged to think about the big questions of science in new ways. These are important issues — and not simple ones.”

Again, my thanks to him for his serious and highly reasonable response to the two books.

Posted in Not Even Wrong: The Book | 16 Comments

Lots of Links

Various things that I’ve run across recently that seem worth mentioning:

The proceedings of the big yearly lattice gauge theory conference that was mentioned here, Lattice 2006, are now available here.

The New York Times today in its Science Times section has a very interesting article by Dennis Overbye entitled China Pursues Major Role in Particle Physics. It tells some of the history of particle physics in China, describes the BEPC accelerator in Beijing which has just had a luminosity upgrade, and discusses the role China may play in future accelerator projects, especially the ILC. A US physicist who sometimes works at BEPC, Frederick Harris, is quoted as saying “The rate China is growing, this is something they could contemplate hosting in 10 years.” Perhaps the future of high-energy frontier accelerator projects really will be in China.

There’s also an associated article about the spring 1989 physics conference in Beijing that overlapped with the Tiananmen Square massacre, with David Gross quoted as saying “Until the shooting began, the visit was delightful.” He and Vafa describe the bloody van that was supposed to be their transport, after it had been used to pick up wounded students, two of whom died.

Physics World has an article about physicists willing to make bets, called Physicists who fancy a flutter, featuring Tommaso Dorigo’s recent $1000 bet with Gordon Watts and Jacques Distler over what the LHC will see.

New Scientist has a feature article Physics Goes Hollywood, about Costas Efthimiou and a course he is teaching at the University of Central Florida. The idea of the course is to have students watch movies, often ones with a sci-fi theme, then use real physics to critique the accuracy of scenes in the movies. Costas is a particle theorist who has worked on conformal field theories, and was a visitor here at Columbia for a while, from what I remember. He has several papers about teachng physics using films, most recently this one.

The Cao-Zhu paper giving the details of the proof of the Poincare conjecture that originally appeared in the Asian Journal of Mathematics has now been posted in revised form on the the arXiv. The revised version includes an apology to Kleiner and Lott for not acknowledging the use of their work in the original version.

Geometric Langlands is definitely the hot topic of the moment, I just learned about two more conferences about this that will take place soon. One is a Gottingen Winterschule, on January 4-7, the second is a program on Langlands Duality and Physics, to be held at the Schrodinger Institute in Vienna from January 9-20.

A couple weeks ago in Hamburg there was a conference on Kahler Geometry and Mathematical Physics, held to celebrate the 100th birthday of Erich Kahler.

Princeton will be hosting a conference next year entitled Geometry and the Imagination in honor of Bill Thurston’s 60th birthday.

Dmitry Vaintrob, son of mathematician Arkady Vaintrob, has won a $100,000 scholarship from the Siemens foundation based on a research project in string topology. For more discussion of this, and what it means for string theory, see here.

Update: Two more.

Giorgios Choudalakis took a poll back in August of grad-students, postdocs and professors associated with Fermilab, asking them what they expected the LHC to find. Here are the results. More about this at Fermilab Today.

A commenter points out that this week’s Zippy the Pinhead deals with one character’s doubts about string theory. Over the last few years, the comic has often dealt with string theory, to see this try typing “string” into this search page.

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Two Reviews

Two reviews by physicists of my book and Lee Smolin’s have recently appeared.

The first is by David Lindley in the Wilson Quarterly. Lindley has written some excellent popular books about physics, including one about quantum mechanics entitled Where Does The Weirdness Go?, and he has a new one about the history of the uncertainty principle that I look forward to reading. He is also the author of The End of Physics: The Myth of a Unified Theory, which appeared back in 1993, and was the first popular book I know of that explained that the project of finding a unified theory of particle physics had started to run into trouble and was not making progress. In some ways Lindley’s book was a precursor to John Horgan’s later The End of Science, and Horgan acknowledges Lindley’s influence. Lindley notes that I say a bit about his book in mine, saying I misstate one of his arguments. He has to be right about this, so I’m rather curious to know what I got wrong (an internet search shows that he has been pretty successful at keeping his e-mail address non Google-accessible, so I haven’t yet contacted him to ask him about this). His description of the books is reasonably accurate and straight-forward, and he ends with the following observation:

As for string theory, it’s likely to unravel only when its practitioners begin to get bored with their lack of progress. Like the old Soviet Union, it will have to collapse from within. The publication of these two books is a hopeful sign that theoretical physics may have entered its Gorbachev ­era.

December’s Physics Today has a review of the same two books by Kannan Jagannathan, under the title Scrutinizing string theorists and their future. One unusual aspect of the review is the peculiar description of the reviewer, unlike any I’ve ever seen before in Physics Today:

Kannan Jagannathan is a professor of physics at Amherst College in Amherst, Massachusetts. Though his background is in high-energy theory, he has no strong stake or expertise in string theory.

It’s an indication of the highly partisan nature of the controversy these books have stirred up that Physics Today seems to have found it necessary to include this sort of unusual disclaimer. It appears true that Jagannathan is no partisan, but his disclaimer of expertise on the subject covered by the books is associated with a rather superficial take on the arguments these books are making. His only attempt to evaluate whether there is anything to the claims Smolin and I make about the problematic behavior of some string theorists is to have read Lisa Randall’s recent popular book Warped Passages, and found that she doesn’t seem to share our concerns.

While avoiding saying anything about the substance of my arguments, Jagannathan does take exception to the style of some of them, suggesting I should use more “temperate rhetoric”, and avoid “anecdotes and private communications.” Perhaps he’s right that tactically it would have been better for me to write a more impersonal book, bending over backwards to appear to not be expressing personal opinions. For better or worse, I chose to do something quite different; to write a very personal book, expressing precisely what I think, and describing experiences that have led me over the years to these opinions.

Posted in Not Even Wrong: The Book | 47 Comments

Media and Other News

There’s filming going on outside my office window today, right at the entrance to the Columbia Mathematics building. The film is Brief Interviews With Hideous Men, with a screenplay based on the David Foster Wallace book of the same name.

On the way in here I stopped at a bookstore and took a look at the new Thomas Pynchon novel Against the Day. Over at Cosmic Variance, Mark Trodden and Sean Carroll are Pynchon fans and have postings about this. I was quite fond of Vineland and enjoyed some of Pynchon’s earlier books, but he lost me with Mason and Dixon, and this new one doesn’t look promising. From flipping through it, one important topic seems to be quaternions and their relation to 4d space-time geometry, and a group of characters are called the Quaternioneers. I almost bought the book, thinking that it was my duty as a chronicler of the nexus of math, physics and popular culture to read the thing. But when I picked it up, its sheer heft caused an immediate feeling of discouragement, so I put it back down and will wait for reports from others.

There’s a new movie out this week called Deja Vu, and evidently string theory play a significant role in its time-travel/multiverse based plot. My colleague Brian Greene was scientific consultant on the film, and the Cosmic Log MSNBC blog has a story about this, noting that he’s also involved in another time-travel movie project (Mimzy), and appeared in yet a third (Frequency). The MSNBC story does explain that time-travel is not a big topic of current physics research, but describes physicists as “intrigued by the trippy concepts spawned by string theory – indicating that the universe could follow any of 10500 possible courses, and that our course seems to be going down just the right path to allow for the development of stars, galaxies and life” (the story does note that some people have a problem with this and gives “Not Even Wrong” a mention). While I gave up on the idea of spending $35 on the Pynchon book and devoting endless hours to reading its more than 1100 pages, spending $10 and devoting a couple hours to watching a cheesy movie seems like a much more viable way of fulfilling my blogger duties, so I think I’ll be doing that this evening.

Continuing on the science fiction theme, next year’s Les Houches summer school will be on the topic String Theory and the Real World.

In further media news, last week I talked with someone from the CBC radio program The Current, and supposedly they were going to use some of this in a program on the controversy over string theory that aired yesterday. Also someone tells me that this past week’s issue of Der Spiegel has an article on this.

Finally, for some non-media science fact, the week before last there was a workshop in Paris on High Energy Physics in the LHC Era. There were quite a few interesting talks, including one by Albert de Roeck on post LHC accelerator possiblities (mainly the SLHC, a luminosity upgrade of the LHC), by Alessandro Strumia on astrophysical neutrino experiments, and by Fabio Zwirner on supersymmetry (see page 18 of his slides for a good reason not to believe in supersymmetry). The summary talk was given by Luciano Maiani, who argued that the next machine after the LHC should be a larger proton-proton machine, on the SSC size scale, to be built in the US (since it wouldn’t even fit at CERN), with an electron-positron collider to be built at CERN.

Update: For a more general discussion of the question of whether new physics that solves the naturalness problem will be visible at the LHC, see a recent posting by Tommaso Dorigo, who is reporting on a conference going on in Bologna, especially the talk by Andrea Romanino.

Update: The movie is completely generic, including no strings, but just a standard-issue wormhole.

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Langlands on Langlands

In a forthcoming issue of the AMS Bulletin, there will be a long review by Robert Langlands of the book p-adic Automorphic Forms on Shimura Varieties by Haruzo Hida. The book itself is on a very technical subject, but the review includes long sections by Langlands that are much more generally about the current state of the so-called “Langlands Program”. While this inspired the “Geometric Langlands Program” that I’ve written about here recently, it’s a quite different subject, one that is very much central to research in number theory. Basically it deals with number fields (extensions of the field of rational numbers), and the function fields of geometric Langlands involve very different issues.

At the same time as making available his review, Langlands also made available commented copies of his correspondence with various experts in the subject about a draft of the review that he had sent them. Much of the review itself is likely to only be accessible to experts, and this is even more true of the correspondence. Casselman comments:

I also have the impression that you have edited this review for the pleasure of experts, and that therefore the cutting-room floor is filled with the sort of stuff The Naive Reader might appreciate.

The response to this from Langlands is:

I had in mind explaining more, but the editing was not a matter of choice but of necessity. I did not understand enough to say more.

I suspect few people will be able to follow the discussion here, but it gives a good idea of what is going on in an active but very difficult area of mathematics.

Both of these documents are from a fantastic resource, a web-site set up by Bill Casselman which contains pretty much the complete works of Langlands on-line. If you want to know more about the Langlands program and where it comes from, there’s lots of material worth reading on the site. One of the more readable sources for a beginner is the 1989 Gibbs symposium lecture on Representation theory- its rise and its role in number theory.

For a lower form of entertainment, there’s another book review, of Leonard Mlodinow’s Euclid’s Window, which appeared in the AMS Notices. The review is pretty much completely over the top, beginning with the sentence:

This is a shallow book on deep matters, about which the author knows next to nothing.

Update: I should also have mentioned that last month there was a small conference at the IAS on The L-group at 40, in honor Langlands’ 70th birthday.

Posted in Langlands | 24 Comments

Esquire On The State of Particle Theory

You know things are getting strange when Esquire magazine starts running an article on the current state of particle theory. As you might expect, their take on this is rather odd. It centers around Nima Arkani-Hamed and begins with:

For a hundred years, physicists have been scraping away at the strange and complicated phenomena obscuring the true face of our universe. Finally, a few brillant young thinkers may be on the verge of getting the first real glimpse.

which is pretty much complete nonsense, totally ignoring the huge success of the standard model in favor of the latest extremely speculative models promoted by some people.

The Esquire writer talked to several theorists, including Lee Smolin and Laurent Freidel at Perimeter, where he describes young postdocs as hanging out at a local hipster bar, with one of their number describing string theorists as “the post 9/11 theocons”, afraid of anything new: “The string theorists just masturbate to their same ideas.” The postdocs do note that at Perimeter string theorists and non-string theorists get along fine. Freidel, a faculty member at Perimeter, is described as not having slept for two weeks straight when he was working on a solution of QCD, with his wife asking a colleague “Can you do something? He’s going insane.”

After describing Perimeter, the article then moves on to Witten and Maldacena at the Institute in Princeton. Witten’s comments about the current state of things go as follows:

Well, you can’t have your best year every year… I’ve lived through two periods, the mid-eighties and mid-nineties, where for about six or seven years, roughly, there were a lot of really interesting results that were also relatively easy. And I’ve also lived through several periods by now where you have to work a little harder to get something interesting.

Witten goes on to say that he is putting his hopes in the LHC and the idea that it is likely to tell us something about the nature of electroweak symmetry breaking.

There’s some attempt to describe Maldacena and his AdS/CFT conjecture, which is characterized as “a mind fuck, but not crazy.” The article then moves back to Arkani-Hamed at Harvard, with “For crazy, you have to go about 250 miles north.” His view of the current controversy over string theory is said to be “forget the antistring polemicists! They’re just reactionaries! This could be the greatest discovery of our time!”, and he heavily promotes the anthropic landscape and the idea that the LHC will provide evidence for it. He says:

The mantra of string theory ten years ago was that the theory was smarter than you… Well, exactly that–just follow the theory where it leads you and it leads to this precipice. And now we have to decide what to do. So now a number of people are deciding to jump… And I think that those of us that decided to take the plunge are staring at the true nature of the beast for the first time.

Personally, I think if a scientific theory with no experimental evidence for it takes you to the edge of a precipice and tells you to jump, the sensible thing to do is to say “No Thanks!”, back away, and go find another theory. But that’s just me.

The latest New Scientist also has something about the string theory controversy, an article by Michio Kaku entitled Will we ever have a theory of everything?, part of a series of articles on “The Big Questions”. Kaku describes the controversy dramatically:

It’s all-out war. The hostilities have begun. With guns blazing, daily salvos are being fired by both sides. Welcome to the conflict raging within the rarefied world of theoretical physics, where a civil war has erupted over string theory and a theory of everything.

While I disagree with the far too rosy picture he paints of the prospects for string theory, Kaku takes a very sensible attitude towards the whole thing:

So who’s right? Actually, both have a legitimate point of view. But far from signalling a collapse in physics, this debate is actually rather healthy. It’s a sign of the vitality of theoretical physics that people are so passionate about the outcome. Science flourishes with controversy.

and ends, reasonably enough with:

One day, some bright, enterprising physicist, perhaps inspired by this article, will complete the theory, open the doorway, and use the power of pure thought to determine if string theory is a theory of everything, anything, or nothing.

New Scientist also asked various well-known physicists what they thought might happen in physics in the next 50 years. Weinberg says that he hopes for a final theory of particle physics, with discovery of superpartners a first step. Tegmark also hopes for a final theory, one which will have us living in just one of many “parallel universes”. ‘t Hooft hopes for a deterministic model that would unify quantum mechanics and gravity, Randall for a new understanding of space and time, Carroll for a theory of the big bang, Wilczek for a new golden age of particle physics catalyzed by the LHC, Kolb for the discovery of gravitational waves and Vilenkin for the discovery of a cosmic string. The most popular question on many these people’s minds is that of whether or not we live in a multiverse (Tegmark, Rees, Krauss mention this). Among mathematicians, Marcus du Sautoy suggests we’ll have a proof of the Riemann hypothesis, Timothy Gowers favors P=NP.

Among all these and other scientists, I think the most plausible prediction comes from my graduate school roommate, Nathan Myhrvold, who thinks a revolution will come from materials science, with the development of new “metamaterials”, substances with new, intricate synthetic structures.

Update: Somehow I hadn’t noticed that New Scientist also had a prediction from Witten:

String theory will continue to be an extremely fertile source of new ideas. It will still be viewed as the interesting candidate for quantum gravity, and may even be more or less understood by 2056.

Interesting that he thinks that 50 years from now the situation will be much the same, with string theory still just a “candidate” for quantum gravity, and he doesn’t predict that we will have string-based unification of particle physics and gravity.

Posted in Uncategorized | 47 Comments