Short Items

Planning on getting back to writing some longer postings, but for today, here’s a collection of quick news and links:

  • I hear from number theorists that Princeton’s Manjul Bhargava has some breakthrough results on the ranks of elliptic curves. I was out of town and missed his colloquium talk here, reports were that it was quite impressive. Here’s the main result, from the talk abstract:

    There is a standard conjecture, originating in work of Goldfeld, that states that the average rank of all elliptic curves should be 1/2; however, it has not previously been known that the average rank is even finite!  In this lecture, we describe recent work that shows that the average rank is finite (in fact, we show that the average rank is bounded by 1.5).

  • There’s an intriguing new paper out from Frenkel, Langlands and Ngo, describing some tentative new ideas about how to prove functoriality using the trace formula. I gather that this combines ideas from Ngo’s proof of the fundamental lemma, ideas of Langlands about “Beyond Endoscopy”, and ideas originating in the geometric Langlands program. The paper is clearly largely written by Langlands (one hint is that it’s in French, be grateful it’s not in Turkish…).
  • Besides this new work, Ed Frenkel also has a new film coming out, entitled Rites d’Amour et de Maths. Here’s the plot summary from IMDB:

    Is there a mathematical formula for love without death? The film ‘Rites of Love and Math’ is a sprawling allegory about Truth and Beauty, Love and Death, Mathematics and Tattoo, set on the stage of Japanese Noh theater. About the directors: Edward Frenkel is Professor of Mathematics at University of California at Berkeley and one of the leading mathematical physicists in the world. Reine Graves is a talented French filmmaker who has directed a number of original and controversial films that have won prestigious awards. Having met in Paris, Frenkel and Graves decided to create a film showing the beauty of mathematics. But how to do this without getting bogged down in technical details of the subject that could scare away non-specialists? Looking for the right metaphor, they came across the idea of making the tattoo of a mathematical formula. What better way to show the beauty of the formula than by letting it merge – literally – with beautiful female body! They found the aesthetic language for expressing this allegory in the enigmatic film ‘Rites of Love and Death’ (a.k.a. ‘Patriotism’) by the great Japanese writer Yukio Mishima, which had a very unusual and mysterious history of its own (banned for over 40 years, it came out on DVD in the Criterion Collection in 2008). The exquisite imagery of Mishima’s film and the original idea of Frenkel and Graves have led to the creation of ‘Rites of Love and Math.’

  • Harvard finally has a female tenured math professor: Sophie Morel.
  • This week’s Science Magazine has an article about Sabine Hossenfelder’s work (also see her blog posting here) purporting to show that you can’t get linear terms in deformed Special Relativity, making deviations from standard Special Relativity unobservably small. Personally, this is the sort of thing I don’t know enough about to offer an informed judgment on, but I’m curious to hear what experts think.
  • Nature has an article about social scientists studying the LHC project.
  • The KITP is now running a program on Strings at the LHC and in the Early Universe, which is a bit odd, since string theory predicts nothing at all about either topic. They’ve had promotional Blackboard Lunch talks by Cvetic and Brandenberger claiming otherwise (Brandenberger’s title was “Testing String theory with Cosmological Observations”). Taking a look at them, I don’t see anything at all that corresponds to a “test of string theory”.
  • Update: One more. See here for Jester’s summary of what particle theory came up with during the noughties, which has to have been the most depressing decade for the subject in a very, very long time.

    Update: There are two new papers (see here and here) on the arXiv this evening that address Sabine Hossenfelder’s arguments about DSR (she also has a new paper summarizing her argument, here). In one of these, Lee Smolin argues that, at least in some cases, the paradoxes pointed out by Hossenfelder can be eliminated if one studies wave-packet propagation instead of classical propagation.

    Update: There’s another unusual paper on the arXiv this evening, by Longo and Witten, entitled An Algebraic Construction of Boundary Quantum Field Theory. It’s an algebraic QFT paper, written in a rigorous mathematical style, quite out of character with typical papers from Witten.

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    25 Responses to Short Items

    1. Egads Itwerks says:

      “Harvard finally has a female tenured math professor: Sophie Morel.”

      Honestly, Peter, who cares about Harvard anymore? Columbia is more important, as are most other Universities. Harvard isn’t to be faulted for hiring Lubos, no, they lost cred the day they gave George W. Bush a Masters degree. No rational person can respect them now. The once proud institution gives new meaning to “yesterday’s newspaper.”

    2. Li Shenjang says:

      According to the new 2010 NRC rankings (yet to be released to the wide audience), Harvard is not even in top 5 anymore. So the answer to the obvious question “would it hire S. Morel if she were a he” is probably a resounding “yes”.

    3. Peter Woit says:

      Li Shenjang,

      What’s going on with the NRC rankings? I remember that already several years ago they were late being released…

      And, Egads, Harvard still has a great math department, whether or not it’s in the NRC top 5.

    4. Bob Levine says:

      The NRC ranking are due to be released late this spring, at last report. My understanding is that the format will be somewhat different; rather than a strict order on departments, graduate programs will be grouped into tiers. It does seem a bit more sensible, doing it that way.

    5. Shantanu says:

      Peter, what do u think about Deser’s talk at KITP? Looking forward to your comments. I think Brandenberger’s talk was about String gas cosmology(an alternative to standard inflationary model)

    6. M says:

      The social scientists write about CERN “its two restaurants live up to their reputation for offering some of the best food of any physics canteen in the world.”

      This is more irrealistic than the CERN airplane invented by Dan Brown

    7. Pingback: Sophie Morel, la primera mujer profesora en el Departamento de Matemáticas de la Harvard « Francis (th)E mule Science's News

    8. Bee says:

      Hi Peter,

      Thanks for the link. Since I just saw that Lubos commented on my recent paper, I hope you will kindly host my reply to him since I know it’s pointless to leave it at his blog.

      It is of course complete bullshit that this recent paper, or any of my previous papers, is the result of communication with Lubos. I did indeed have an email exchange with Lubos about DSR at some point. I have repeatedly, and fruitlessly, tried to tell him that the model I’ve been working on does not have an energy-dependent speed of light. That model dates back to 2003 as one can easily see from my publication list. Lubos has failed all the years to grasp this simple fact. His misunderstanding is documented on various of my and his blogposts. This isn’t the place to explain what’s behind my model, but who is interested can check out this blopost. Up till today I don’t know if Lubos really didn’t understand that or if he just pretended to so he had a reason to proclaim I’m dumb.

      To address another particularly nonsensical remark in Lubos’ blogpost: Neither Lee Smolin nor anybody else has ever “pressured” me to write a paper. That I started writing papers on DSR after I went to PI is obviously because I started to get more interested in the topic. I first tried to figure out what the relation is to my model, documented here and here. I then wrote two papers about what I think are the biggest problems of DSR, the so-called soccer-ball problem and the formulation in position space. The latter paper was a precursor to the more recent paper.

      Even though I’ve thought an energy-dependent speed of light to be incompatible with observer-independence (which is why I didn’t consider the option in my 2003 paper) it wasn’t so easy to show after all. Sometimes I thought it might work, but then again it didn’t make sense, then I tried something else, that didn’t work either, then I thought I might have missed something, etc.

      It adds to this that I’m not particularly happy poking holes in other people’s models, I’d rather have something more promising to offer myself. The recent paper actually came about because I was trying to figure out if there is a way to distinguish deformations of Lorentz-invariance from breaking of Lorentz-invariance by taking measurements in two different frames (say the Earth and a satellite), but I ran into some problems there. I wrote up my notes on that and dumped them on the arXiv. I frankly didn’t expect them to get this attention, in particular not since the problems with locality had been pointed out previously by Unruh and Schützhold (and in my earlier paper). It’s just that nobody ever put the numbers in. That’s what I did. Turns out the nonlocality is far larger than even I expected it to be. So it seemed worth writing up.

      Best,

      Sabine

    9. Chris Oakley says:

      Bee,

      If you insist on taking Lubos seriously, Peter does have a “Censored Comments from the Reference Frame” entry which I think still accepts comments:

      http://www.math.columbia.edu/~woit/wordpress/?p=412

      Although it is an old post, new comments will show up in the right-hand column here.

    10. Peter Woit says:

      Bee,

      Thanks for the further explanations of this.

      Chris,

      The current configuration of the blog shuts off comment threads after some predetermined length of time. I’d rather people don’t respond here to Lubos’s rantings, unless it’s on-topic (as Bee’s comment very much was).

      Shantanu,

      Deser seemed to me to be saying nothing new or surprising.

    11. hv says:

      «It adds to this that I’m not particularly happy poking holes in other people’s models, I’d rather have something more promising to offer myself.» Lubos’ offer is simply the plain old Lorentz invariance. His point often being, if there’s nothing reasonable and/or justified to offer, then don’t! And pointing holes in models should be compulsory in any theoretical science, especially if you know they’re there! It makes issues in science less foggy. Is Lubos harsh in his discourse? Yes, he his! But afaik his points are correct. Mind you, Nature isn’t polite either.

    12. Peter Woit says:

      hv,

      The problem with Lubos is not just that he’s impolite. He’s a fanatic, and like all fanatics is devoted to misunderstanding and ignoring facts that disagree with his preconceptions. The rudeness makes it extremely unpleasant for anyone who tries to take on the task of correcting something he is wrong about, and the fanaticism ensures that he’ll never acknowledge error.

      Enough though about Lubos. It’s depressing to put up postings mentioning a range of interesting topics, then find that all people want to discuss is Lubos the minute some reference is made to him.

    13. Sacre Bleu !! says:

      what particle theory came up with during the
      noughties, which has to have been the most depressing decade
      for the subject in a very, very long time.

      The idea being, I gather, that any progress in particle
      physics (say, advances in jet algorithms or QCD perturbative
      computations) is extremely boring, whereas any incremental
      result in some obscure subfield of number theory is
      fascinating, especially if it has been written in some
      Quartier Latin’s dialect of French.

    14. Lubos Motl says:

      An anonymous unfriendly person – a reader of yours, Peter – has sent me a link to your blog, Peter. I haven’t heard about the blog for years but it’s good to see it’s still alive. But not too good. ;-)

      Interesting conversation. Concerning your frustration: Well, let us admit that I am by far the most interesting topic you have ever discussed on your blog, so the mindless zombies who keep on visiting your crappy website even years after it’s been shown that you are just a grumpy dishonest crank are unsurprisingly excited by this topic. Get used to it. You owe everything to me.

      The whole point of this collapsing website has always been to poison people and slander physics and physicists. The whole point was to claim that there was nothing interesting or valid going on in theoretical high-energy physics – which mostly means string theory. The whole point was to make people frustrated, bored, upset, and misled.

      So it is pretty surprising to hear that you think that you are offering “interesting topics”. You have never offered any interesting topics or ideas in your whole life, Peter. Even the most hardcore mujahideens who still keep on visiting this site know that which is why they’re trying to discuss the only remotely relevant interesting topic which just happens to be myself at this point (although I would surely modestly disagree that I am the most interesting topic – but among the topics that are accessible to limited people who have been brainwashed by your stupidities for 6 years, I probably am). ;-)

      [arguments/threats directed at someone else deleted]

    15. Bee says:

      hv:

      The thing is that what’s “reasonable” and “justified” is not an objective criterion. Different people may have different opinions on that, and these opinions will typically differ depending on the context of their work and their interests. One of the key motivations to consider the particular type of deviations from Special Relativity that my paper comments on is that Special Relativity does not respect the invariance of any (finite, non-zero) energy scale. If you believe the Planck mass is a physically meaningful UV regulator, then it should be the same in all restframes, so the argument. You can’t do that with usual Lorentz-transformations. Thus, you need a modification of Special Relativity to achieve the invariance of the Planck scale.

      Now I’ve argued (in one of the papers I mentioned above) this is not the right way to think about the invariance of the Planck scale, but then I do not think it’s an “unreasonable” motivation either to examine such deviations from Special Relativity. Best,

      B.

    16. It is ridiculous to say that Harvard is not important anymore. They have Jacob Lurie! I’m not a category theory person, but it cannot be denied that what Jacob Lurie is doing is ground breaking work. Yes, Columbia has some impressive people, but Harvard is still one of the best math departments in the nation.

    17. anon. says:

      One of the key motivations to consider the particular type of deviations from Special Relativity that my paper comments on is that Special Relativity does not respect the invariance of any (finite, non-zero) energy scale. If you believe the Planck mass is a physically meaningful UV regulator, then it should be the same in all restframes, so the argument.

      On the contrary. Lambda_{QCD}, or maybe 4pi Lambda_{QCD}, is a UV scale if you’re talking about pion physics. And it’s not Lorentz invariant. Is this a problem? Of course not; it’s only if some invariant quantity is larger than Lambda_{QCD} that it’s sensitive to the UV completion (QCD). It’s true that this is simple field theory, not deep and mysterious quantum gravity, but I don’t see why the fact that quantum gravity is deep and mysterious should lead you to conclude that all the rules have to change.

    18. anon. says:

      To clarify, my “it’s not Lorentz-invariant” means “it’s not Lorentz-invariant if viewed as a cutoff energy.” The point, of course, being that the cutoff is not in energy but in invariant kinematic quantities.

    19. anon. says:

      I now recall that I made the same point on your blog several years ago, Bee. I’m not sure if I’m failing to convey the point or if you have some argument I’ve missed.

    20. ? says:

      Somebody must ask this: the 1st female math professor at Harvard is there because she was the best candidate, or because Harvard now has a radical feminist president and a lot of $ for “diversity efforts”?

    21. Peter Woit says:

      ?,

      Morel is an excellent mathematician, not at all out of place among the list of other Harvard senior faculty. One could also note that she started her career with admission to the ENS in Paris, which is by competitive exam. If one is going to try and make the case that affirmative action is a problem at American universities, she’s not a helpful example.

    22. willman says:

      Anon,
      Bee’s conclusion, as I understand it, is that the Planck energy does not in fact need to be an invariant of Lorentz boosts (see p. 18 of her “Box-problem” article); thus, I don’t see any actual disagreement between you and her on this point. Bee also claims that the Planck scale needs to be observer-independent if this scale is truly fundamental; but I’m not sure why this claim is any more controversial than the idea that taking the velocity c of light as fundamental involves taking c to be observer-independent.

    23. chris says:

      thanks for this very interesting link to the sociology of the LHC project. i really loved this sentence:

      “Social scientists say they earn the trust of the physicists at CERN by immersing themselves in the culture, just as they would with any other population.”

    24. Thomas Larsson says:

      The Longo-Witten paper made me raise an eyebrow, too. Unfortunately I never managed to become confortable with AQFT, so I will have a hard time reading it.

    25. Amos says:

      It would be helpful if someone were to put together a post discussing in detail this issue of the observer-dependence of the Planck scale, and the different sides of the question.

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