Not Even Wrong

The latest “This Week’s Finds” by John Baez discusses Felix Klein and his “Erlanger Programm”, which essentially was the idea that geometry should be understood as the study of Lie groups G, their subgroups H, and coset spaces G/H. This, supplemented with Cartan’s notion of a connection, allowing things that only locally look like G/H, is very much at the heart of our modern view of geometry. John gives links to quite a few things worth reading by and about Klein here. Another very interesting document is Klein’s own history of 19th century mathematics “Development of mathematics in the 19th century”.

I’m very much looking forward to the next installment of TWF, where John promises some insights into Hecke algebras. He also has a wonderful posting that generated an interesting discussion at the n-category cafe on the topic of mathematical exposition, entitled Why Mathematics Is Boring.

For some more mathematics blogging of the highest possible quality, see Terry Tao’s postings on his Simons lectures at MIT, here, here and here.

I wrote a bit about the LHC Theory Initiative here last year. They have just announced the award of two graduate fellowships and say that they will be awarding postdoctoral fellowships in the future. Unclear from this if they were successful in their efforts to get NSF funding, the solicitation of applications for the fellowship just mentions an older grant to Johns Hopkins.

NPR has run a two part series on the LHC (here and here). The first part features CERN theorist Alvaro de Rujula. I had the great pleasure of taking a particle theory course from him when I was a student at Harvard a very long time ago. He cut an impressive figure, and provided a survey of the subject that was both enlightening and entertaining.

Scott Aaronson provides quotes from someone else (Gian-Carlo Rota) whose lectures I attended around the same time, including one that ends “You and I know that mathematics, by definition, is not and never will be flaky”. I kind of agree with the sentiment in the full quote, but my experience with Rota back then was a rather weird one. For some misguided reason I had decided that since category theory was the most abstract kind of mathematics I had heard of, it would be a good idea to take a course on it. The only course on the subject was a graduate course down at MIT offered by Rota, so I started going down there to sit in on it. A few lectures into the course Rota all of a sudden announced that he had decided that only those students actually enrolled for credit should be taking the course, and that the several of us who were just auditing should leave. So we did, somewhat mystified (it’s not like the room was over-packed or anything). To this day, I still don’t know what that was about. Perhaps Rota knew that he was doing me a favor by stopping me from thinking about category theory at that point in my education, when in retrospect it seems likely that it really would have been somewhat of a waste.

There’s a lot more about Rota at this web-site. His capsule reviews in the back of the journal he edited, Advances in Mathematics, provided outrageous entertainment for many years (although some might at times think that they were, well, flaky…).

This past weekend I was at the University of Central Florida, participating in a symposium organized by Costas Efthimiou of the physics department there. It was sponsored by two student organizations, the university’s Society of Physics Students and Campus Freethought Alliance. There were two speakers, Jim Gates and myself. I suspect that the organizers and many in the audience were hoping for some fireworks between Gates and myself, taking opposite sides on the controversy over string theory, but I fear that we disappointed them.

My talk was entitled The Challenge of Unifying Particle Physics, and my intention was to avoid spending much time going over the problems of string theory, since I’m pretty tired of that, and instead to try and explain to the audience some of the basic facts about symmetries, representations and quantum mechanics, together with an outline of the current state of efforts to unify physics. Gates gave a very general talk about particle physics, unification and string theory, featuring a lot of very impressive graphics he has developed as part of a multi-media course called Superstring Theory: The DNA of Reality.

In the end, there wasn’t that much for us to disagree about. My critique of string theory as a unified theory is based on the claim that the idea of using strings in 10d doesn’t work because the variety of possibilities for handling the extra 6 dimensions makes predictions impossible. Gates has always been skeptical about extra dimensions and wasn’t about to defend them, let alone the landscape. I take his general attitude to be similar to that of Warren Siegel, who he collaborated with in the past, and who explains his point of view here. Recently Gates has been very much interested in representation theory, in his case the representation theory of supersymmetry, where he and collaborators see fundamental problems still to be resolved, and have new ideas about using Clifford algebras to attack them. For one of their recent papers written from the more mathematical end of the problem, see here.

I very much enjoyed my time in Orlando; high points were getting to meet with and talk to some of the physics students there, meeting someone who sometimes comments here who came to the talk, and especially getting the chance to discuss things with Jim, who I found to be impressively knowledgeable and thoughtful about every topic that came up.

It seems that the MiniBooNE neutrino experiment at Fermilab is finally ready to announce results. A talk next Wednesday, 11am, at Fermilab by Janet Conrad and William Louis has been scheduled, with title Initial MiniBooNE Oscillation Results.

Via Alexey Petrov, who explains the significance and teases that there’s a rumor that MiniBooNE sees “something interesting”…

The list of speakers for Strings 2007 is now available. Titles of talks are not available, but as far as I can tell they’re not taking up Lee Smolin on his suggestion that they have someone there to talk about developments in the LQG approach to quantum gravity that string theorists might find interesting. Also, no mathematicians on the list and fewer mathematically inclined string theorists than at Strings 2006. One experimentalist from CERN (Rolandi), presumably to talk about the LHC. Lots and lots of people who work on the landscape and various string compactification schemes, with the Stanford group well-represented.

If you’re in Princeton tomorrow there are a couple of interesting math talks. The talk by Simons at the IAS on Some Results in Differential Cohomology (with Sullivan, presumably about this) should set some kind of historical record for the highest net worth of a speaker giving a technical math talk. Ed Frenkel is giving the colloquium at the math department on Langlands Correspondence for Loop Groups; I wish I had time to go down there to hear it.

The conference in Paris on non-commutative geometry in honor of Alain Connes is continuing this week. Fabien Besnard reports on the talk by Michael Atiyah, where evidently there was some commentary on the role of mathematical beauty in physics, and warning to the young that working on the kind of idea he was discussing would be dangerous for their careers. And no, in French “Physique Retardee” does not carry the same meaning as a naive translation to English would imply…

The web-site of representation theorist Ivan Mirkovic has lots of interesting things, including notes about geometric Langland and the recent work of Witten-Kapustin-Gukov. Another interesting representation theorist web-site is that of Alistair Savage, which includes various lecture notes and an overview about quivers and geometric representation theory.

See here for the program and some lecture notes from the recent spring school at Trieste. Especially interesting are the lectures by Martin Schmaltz about Physics Beyond the Standard Model and the LHC. The Resonaances blog also has a report about a recent talk by Schmaltz at CERN. The bottom line seems to be that, contrary to what was previously thought, in many of the kinds of supersymmetric models supposed to come from string theory, you can’t run the observed scalar superpartner masses back up to the unification scale, so, even if you see such things, you won’t get information about grand unification out of them. Schmaltz gives a graphical representation of the reaction of various people to this. I’m in category A.

Tommaso Dorigo has an excellent suggestion for experimental collaborations worried about the information that their blogging members are putting out. Don’t fight them, join them! He suggests that large experiments like CDF, D0, ATLAS, CMS should be putting out a collaboration-approved blog, getting their story out to the public through this medium.

Update: I realized there is another event I should mention. This Saturday I’ll be giving a talk at a symposium at the University of Central Florida in Orlando, organized by the Society of Physics Students and the Campus Freethought Alliance. Also speaking there will be Jim Gates, who presumably will be taking a somewhat more optimistic view of string theory. I’m still trying to figure out what to talk about, current plan is to cover some of the material in my book, emphasizing the parts everyone ignores that are not about string theory…

Bloggingheads.tv now has some video up with an interesting discussion between John Horgan and George Johnson on a range of topics. One segment is entitled String theory deemed load of crap!, and discusses the controversy over string theory. Both Horgan and Johnson agree that things are not look good for a physical theory when there start being public debates on the subject. Johnson also discusses his time at the KITP and mentions this blog. He seemed to be particularly struck by the behavior of the participants at the session he ran there which involved a lot of bashing of Lee Smolin, with Mark Srednicki raising his hand when Johnson said he didn’t think anyone would call Smolin a crackpot.

Johnson also described the “echo chamber” effect of blogs like this one. I guess I better keep this going by blogging about his commentary about my blogging…

Update: Sean Carroll has a posting about this over at Cosmic Variance entitled String Theory is Losing the Public Debate. Probably best if people join the discussion over there, which so far includes John Horgan and others.

Update: If you like this sort of thing, more blog discussions about string theory here, here, and here… and here and here.

This latest news from the LHC does not sound good. One hopes it won’t affect the LHC schedule.

Update: Also discussed at the Resonaances blog from CERN.

Update: Latest (4/3/07) news here.

Shelly Glashow is traveling around, giving talks bashing his childhood hero Isaac Newton (and noting that he was “surely one of the greatest intellects the world has known”). He’ll be at NYU tomorrow talking on The Errors and Animadversions of Sir Isaac Newton. For a copy of his talk, see here, (and here for a summary in Catalan).

Tonight is the Lawrence Krauss – Brian Greene string theory debate in DC, and next week in Berkeley Krauss is debating John Terning on the subject, at an event entitled Extra Dimensions and String Theory: Physics of the Future or Pure Mathematics? The event is organized by the FQXI funded organization Multiversal Journeys.

Krauss was at the cosmology conference that Tommaso Dorigo has been reporting on, giving a dinner talk dissing anthropic reasoning and pointing out that cosmology has a “miserable future”, since everything is receding from us. His main conference talk was evidently not very optimisitic about near-term prospects for learning more about dark energy or dark matter.

For more about non-commutative geometry and number theory, David Kazhdan is giving a talk at Harvard on April 18 with the following abstract:

Discussion of Alain Connes formulation of the Andre Weil’s theorem. [ the Riemann conjecture for the functional filed case]. Alain Connes found a very interesting way to interpret the results as a computation of an asymptotic of a family of operators of finite rank.

Lieven le Bruyn has a discussion of Plato’s cave and a recent paper Modular shadows and the Levy-Mellin infinity-adic transform, by Marcolli and Manin, who motivate their title by relating Plato’s cave and holography in AdS/CFT.

Update: The Washington Post’s publication Express has an article about Lawrence Krauss and the problems of string theory, entitled Frayed String.

Update: Science has a report on the debate. Also, there’s a report (with audio) from a blogger at the Hooded Hawk blog.

Last week Princeton hosted a workshop on Physics at LHC: From Experiment to Theory. Many of the slides of the talks are available here. The talks covered a wide range of ground, from theory not obviously relevant to the LHC to reports on the status of experiments. The talk by Michael Tuts of ATLAS reports that they may be roughly 5 weeks behind schedule, with nominal schedule setting the start of beam commissioning at 450 GeV late in November. 7 TeV beams won’t be available until summer 2008, with first physics run perhaps in July, and about 10-100 pb^-1 during 2008, giving similar statistics to what the Tevatron has today for some processes. It looks like it may be the 2009 run that will most likely produce data that will go beyond the Tevatron results, although if the Higgs mass is about 150 GeV, there may be evidence in the 2008 data. Plans for a luminosity upgrade in 2015 are already proceeding.

There was also a plan for a meeting of the String Vacuum Project at the workshop, with a discussion paper available here (via their Wiki).

This week, also down in Princeton, but at the IAS, there will be a Workshop on Homological Mirror Symmetry and Applications, mainly devoted to recent work on geometric Langlands and its relation to mirror symmetry. Since I had to teach I couldn’t make it down there today, so unfortunately missed the first talks by Kapustin and Witten, as well as that of Edward Frenkel, but I’m looking forward to going down tomorrow and maybe later in the week to hear some of the talks.

Warning: There’s not much science in this posting, just mostly people behaving badly. You would be well advised to skip this one, unless you find this kind of thing entertaining…

Long ago, as a public service, I set up a posting to hold comments censored by Lubos Motl, since his preferred way of dealing with people who make comments he finds hard to answer is to delete them. It appears that now a place for inconvenient comments censored by Clifford Johnson at his blog Asymptotia is also needed. If you have a copy of a substantive comment deleted from there or want to discuss one of these, you can use the comment section here.

Since the first thing censored was one of my comments, I’ll provide a little background, then reproduce the censored material I have access to.

This exchange began with this comment from Clifford, which seemed to me to be little more than an out-of-control personal attack and rant, so my only response to it was:

Clifford,

As time goes on and the failure of string theory becomes more apparent, you are starting to rant in a manner which is converging with that of your junior colleague at Harvard. You should get a grip.

Not very long after I wrote this comment, the following comment appeared from Lubos Motl:

Dear Mr Woit,

All the best
Lubos

This was followed by a similar comment attacking Smolin for what he had written about the black hole information paradox, and Smolin responded with a short and polite answer (I don’t have copies of these).

Clifford has edited my original comment, removing “in a manner which is converging with that of your junior colleague at Harvard”, and replacing it with “…snip … – personal reference deleted -cvj”. He has also removed the comments from Lubos and the response by Smolin, replacing them with this comment. Here he claims to have deleted these comments without reading them, since, for undisclosed reasons, he has a policy of deleting all comments from Lubos. Whatever the reason for this policy, he does want to make clear to everyone that he has a high opinion of Lubos as a scientist, and for his work at the Reference Frame “widening the discussion” about physics:

Since I have a great deal of respect for his ability as a physicist, however, if he was making a physics point in his comments, perhaps he might make it on his blog and link to this discussion via trackback. I thank him for his physics contributions and widening the discussion.

I recently noticed that, around the same time I was preparing my slides for a talk about Is String Theory Testable?, Michael Douglas was doing something similar, preparing a talk on Are There Testable Predictions of String Theory? There’s a certain amount of overlap in our presentations, and people might find it interesting to compare them.

Douglas goes over much the same story I do, but reaches different conclusions. For him, string theory does “make predictions”, just lots and lots of incompatible ones, so the problem is that:

none of the ideas which have been suggested so far are guaranteed signatures of string theory. We would be happier with one prediction, which could lead to a decisive answer either way.

This is the sort of thing I would call a prediction, so I guess we agree that they don’t exist. Douglas ends by noting that the one way he can think of to get such a prediction is through a statistical argument based on counting vacua and the dynamics of eternal inflation. He doesn’t mention the argument given in my talk that this is already falsified (by the lifetime of the proton), or that such arguments inherently lead to calculations that are inherently intractable and can never be done (this argument is due to him and Denef, it is surprising that he doesn’t mention it).

Along the way, Douglas does make a couple claims about things that he thinks the statistical anthropic landscape arguments disfavor, especially varying constants and large distance modifications to gravity. Seeing these would falsify our current theory, but would not falsify string theory, since it can accomodate them, although perhaps not within Douglas’s statistical framework.

One of the more surprising responses I’ve seen to my recent claims that string theory has failed as an idea about unification because it’s inherently untestable comes from Mark Srednicki, who writes (in the context of mentioning an MSNBC interview with Brian Greene):

We see that the big issue for Brian, and for just about all scientists (though with the apparent exceptions of Lee Smolin and Peter Woit), is what is TRUE. Not what corresponds to some philosophy of what science is or is not. Lee writes that the landscape must be rejected because “it would mean the end of our field” (page 165). It should be obvious that this is not the basis that is traditionally used for accepting or rejecting a theory! Peter’s (essentially the same) argument that string theory must be rejected because (at the moment) it does not appear to be sufficiently predictive (for Peter) is also irrelevant to the question of whether or not string theory is TRUE.

If the landscape is right, we may never get anything more than circumstantial evidence that it’s right. But that’s often the case in science. We’ve been spoiled in particle physics by having extremely precise data and highly predictive and quantitative theories for the past few decades. Most of the rest of science has not been so lucky. Perhaps we will not be so lucky going forward. The only way to find out is to do more work and see where it leads.

Srednicki’s reaction to the lack of testability of string theory seems to be that testability is not what matters. What matters is what is TRUE, and it’s perfectly logically consistent for string theory to be of such a nature that we can never test it. The problem with this point of view is that science is not so much about what is true as about how one knows what is true about the world. Religious believers are also interested in what is true and think they know what this is, but science is different since it provides a means for deciding what is true. Scientific ideas about the universe are true when they make predictions that can be checked in a convincing way. Ideas that can’t be experimentally checked in some way, directly or indirectly, may or may not be true, but they’re not scientific ideas, rather something of a different nature.