SUSY 2012, and Strassler on the String Wars

This post was originally going to be just about the latest SUSY exclusion results announced at SUSY 2012 and their significance, but I realized there’s nothing much new to say, and it would be tedious to just write the same things. ATLAS new results are here, including some using this year’s 8 TeV data. As before, not a hint of SUSY in the CMS or ATLAS data. Now that the expected places to find SUSY have shown nothing, emphasis is on how to search more obscure corners of the 100 + parameter space of the theory which are accessible at the LHC, but hard to study. For a good recent survey of this effort, see Matt Reece’s recent presentation here.

SUSY 2012 featured a plenary talk by Gordon Kane, promoting his string theory “predictions”. As usual, the gluino is right around the corner. Back in 2000, it was supposed to be around 250 GeV, with SUSY discovery at the Tevatron in 2001-3 (see here). Last summer the “prediction” was 600 GeV, just above the 500 GeV limits. Last December, the gluino discovery was imminent, by summer 2012. The latest news is that the gluino mass prediction is now 1 TeV, just above the 800 GeV limits according to Kane. You can watch the gluino move by comparing the same “prediction” plot on slide 22 here and slide 34 here. Kane now claims in bold face that “String/M theory prediction is that no gluino signal expected so far” (page 35) referring (I think) to this paper, which seems to say nothing of the kind. This is just getting more and more bizarre.

Matt Strassler (described here as “the chief US theoretician”) has rarely been critical of string theory hype (although he did in a comment refer to Kane’s claims as “garbage and propaganda”), preferring to see prominent blogging critics of string theory and SUSY hype as the bigger problem to deal with. Today though he took a dramatic and rather admirable step, with a posting about string theory that starts off with:

…the theory’s been spectacularly over-hyped, and the community’s political control of high-energy physics in many U.S. physics departments has negatively impacted many scientific careers, including my own.

He goes on to cast himself as a lonely moderate surrounded by two teams of extremists, arguing that

it is high time the ball were grabbed by the referee and placed quietly in the middle of the field where it belongs.

His refereed position in the middle of the field would have acknowledgement that “string theory cannot be tested at present, and that situation might continue for a very long time, perhaps centuries”, while lauding string theory for providing a range of important insights into other problems than unification. This refereed position seems to me already pretty much the mainstream position of string theorists I know. My problems with it are that it still allows the heavy promotion of a failed idea (string unification as “our best bet”, even if mysteriously “hard to test”), and the over-hype problem is also prevalent among discussion of string theory applications to other parts of physics.

Strassler gives an interesting example of how some ideas from string theory ended up providing inspiration for advances in amplitude calculations, although the main heros of the tale are the phenomenologists who have done the hard work behind these advances (see his exchange with the anonymous “dude” in the comments).

Oddly enough, what seems to have motivated Strassler to take this new public stand are the recent $3 million prizes awarded to his colleagues down the road at Princeton. He devoted this recent posting to attacking me and Nature News for quoting me about the prizes, but ended up agreeing with some of my concerns, specifically:

What upsets me is that there is a long, long list of deserving scientists, some of whom have received little recognition despite their important work, and some of whom could really use some research money and/or time off from teaching — and Milner overlooked them all…

Philanthrophy needs to be done with the consent and participation of the beneficiaries; otherwise it generally fails, and sometimes it causes complete disasters. For instance, you can completely destabilize an organization that is functioning well if you just hand one of its members a million dollar check without understanding the implications…

Anyway, as far as I can tell, the Milner prize is one thing our field didn’t really need. I can think of a few things we really do desperately need, at least in the U.S.

It’s pretty clear where Strassler thinks the money should have gone:

we have too many string theorists teaching at the top U.S. universities, and not enough theorists doing other aspects of high-energy physics, including Standard Model predictions…

He explained in the earlier posting that he has been trying to raise private money for an LHC Institute, but that this has failed because of the recession. I don’t know any details of this, but I do know that about five years ago he and Arkani-Hamed were proposing something like this to the NSF, with the two of them as co-directors. This foundered not because of the recession but because reviewers didn’t much like the idea of giving a lot of new money to well-funded theorists at Princeton and Rutgers, largely to retool string theory groups into LHC phenomenology groups.

That proposal advertised the likelihood of discovery of SUSY or something equally dramatic about a year after first beams at the LHC, with a large group of theorists needed to sort out the “LHC Inverse Problem” of how one was going to figure out the underlying physics responsible for the confusing plethora of non-SM signals the LHC would be seeing. Perhaps a reason for finding it hard to get funding for a theory LHC institute these days is not the recession, but the lack of any such advertised signal. On the other hand, with $12 million of cash in their pockets now, the IAS theorists should be able to themselves privately fund the proposed Arkani-Hamed/Strassler center, if they still think this a good idea.

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38 Responses to SUSY 2012, and Strassler on the String Wars

  1. anon. says:

    Gordy’s backup slides are still touting the Fermi-LAT 130 GeV gamma ray line as a possible signal of wino dark matter. This is a superficially attractive idea that is completely incompatible with the data from continuum gamma rays, among other bounds. He also is quoting out-of-date LHC bounds, which now put gluinos decaying through off-shell third generation particles above 1 TeV, not just 800 GeV.

    It’s frustrating for those of us who sympathize with some of his arguments against other popular approaches to model-building that he’s so overzealous in promotion of his own ideas that no one takes him seriously anymore, and attempts to argue along similar lines are treated as presumptively not worth listening to….

  2. Bernhard says:

    Does anyone know if there was any audience reaction to Kane´s claims? He went to the biggest BSM conference to tell those lies? I fear that if he says enough times people will start believing he did what he claims (predicting the Higgs mass with gluinos always around the corner, despite of what he said the day before).

    One could say nobody take him seriously anymore, but then again, he was invited for a plenary talk in one of the most disputed conferences in HEP…

  3. Bernhard says:

    Sorry, for two comments, but I can´t resist: “Physicists at CERN believe that we’ll probably first encounter supersymmetrical particles in early 2015, when the power of the Large Hadron Collider will have increased by a factor of two.”

    We are back in time, it´s 3 years ago again and we juuust need to turn on the machine to find SUSY! It´s hilarious!

  4. SteveB says:

    I had read Strassler’s comments before your post. I didn’t get the impression that he was claiming to be “the” referee, but was using the sports analogy to hope for more middle ground. (I believe he would say he is in this middle ground.) I don’t think you should get on his case (even though you did it rather mildly) for only recently commenting on the over-hype. He hasn’t been doing a public blog that long, and it has mostly been educational rather than commentary. Even when doing commentary, it isn’t a requirement that one must speak out on all one’s positions, knowing that attacks will be coming. I could not do what you do — my skin is not nearly thick enough to endure the responses — so thank you again for this blog. But not everyone is so willing.

  5. Peter Woit says:

    SteveB,

    I was quite serious when I described as admirable his finally criticizing the over-hype problem. Would have been even more admirable if he’d done it earlier. The situation in the particle theory community for decades has been kind of grotesque, with most people privately agreeing that the situation with string theory was problematic, few willing to say so publicly for fear of retribution. I hope we’re seeing a change in this environment, towards one where people can have honest conversations about the issues, without fear that someone is going to come after them personally for disagreeing with them about a scientific issue.

  6. mhm says:

    So we want the ball in the middle of the field. Ok. The teams playing are string theory, and who else exactly? More garbage on random BSM model building?

  7. Eric says:

    I think it should really be pointed out that the most likely scenario involving SUSY at this point is that with R-parity violation. In SUSY with R-parity violation, the LSP is no longer stable and so there are no MET signals. All current SUSY searches to date have looked for these MET signals assuming R-parity is conserved. So, R-parity violating SUSY is basically unconstrained by any of the current data from LHC.

    It should also be mentioned that R-parity was only added ad-hoc to the MSSM in order to eliminate operatorators which allow rapid proton decay. In certain extensions of the MSSM, it is possible eliminate the problem of rapid proton decay in other ways. In particular, if there are extra local U(1) factors which couple to either baryon or lepton number, then the B and/or L violating operators can be eliminated, also stabilizing the proton from rapid proton deay. In this scenerio, it is not necessary to invoke R-parity, and models of this type are basically unconstrained by LHC limits on superpartners.

  8. physicsphile says:

    Eric,

    Isn’t R-parity also needed for the MSSM to provide a sufficiently stable dark matter candidate?

  9. APP says:

    Eric,

    The experimentalists are well aware of RPV SUSY and many searches have been done for the modified MET-free signals (typically multi-jets or multi-leptons). The limits on sparticle masses are almost as stringent as the R-parity conserving case — 1st/2nd generation squark mass lower bounds in range 700 to 760 GeV (ATLAS 7 TeV data), and gluino mass bounds in range 760 GeV to 1.77 TeV (ATLAS 7 TeV data). In other words RPV doesn’t buy you very much, unless one sits at rather special points where other things happen as well (like significant displaced vertices, see recent paper of Peter Graham etal http://arxiv.org/abs/arXiv:1204.6038). If low-energy SUSY is somehow hiding within the LHC data it is doing it in a much cleverer and more subtle way than straightforward RPV.

    Physicsphile,

    You are correct that R-parity conversation can give a dark matter (DM)
    candidate, but in fact it has been known for many years, at least 10, that standard SUSY neutralino DM is quite finally-tuned. In much of R-parity conserving SUSY parameter space one does NOT get a successful DM candidate. The SUSY-DM connection is one of those things that has been way overhyped. Many of us working in the field have thought that the Peccei-Quinn-Weinberg-Wilczek axion (with suitable axion decay constant—there is disagreement about the “best” value) is more likely as the DM.

    Peter,

    Many of us working in high-energy particle theory have for years argued against the domination of particle theory by string theory, especially at the “top” US/European universities which train the majority of the next generation of theorists (there have been exceptions, especially Berkeley, MIT, U Wash, Oxford, Pisa, but even these are under threat). However, like Matt, we have chosen to do this behind the scenes believing this the strategy more likely to succeed. It’s certainly true that we haven’t been all that good in resisting/reversing the takeover by string theory! This continuing takeover is greatly assisted by a) the books by Lisa and Brian which persuade many very bright students that the most exciting area is string theory, and b) the prize- and grant-giving bodies which still greatly favor string theory, partially because the older generation of famous theorists who make the decisions are dominantly strong supporters of strings. Among the most famous US theorists, probably only Frank Wilczek has publicly argued that too many resources were going into ST (though others have done so behind the scenes). The Milner Prize probably makes this whole situation worse so I can understand Matt’s frustration. I should say that I’m happy for ST to get reasonable support. The problem, as you’ve said, is that too many resources have gone into an area that isn’t really physics because most of the answerable questions are purely theoretical and have no relation to any conceivable experimental probe (Kane’s “predictions” are not predictions at all but reflections of many special choices he’s made—no one outside his small coeterie takes him seriously). Sadly for all the students who decide to work in ST the field is in a bad way with very little interesting work going on—witness the growth AdS/CFT “condensed matter” physics which most condensed matter physicists view as not having anything to do with real systems and having discovered no new phenomena.

  10. Bernhard says:

    mhm,

    ST is not playing at all, is has its own separate game and it doesn’t invite outsiders to play with. Luckily nobody else wants to play with it anyway.

  11. Peter Woit says:

    APP,

    Thanks for the comment about RPV theories!

    That string theory has been heavily overhyped isn’t at all a controversial claim, with even most string theorists privately agreeing this is the case (and complaining that they are now suffering from the backlash due to hype they weren’t responsible for). It’s remarkable though how few physicists have been willing to be quoted about this publicly. One reason is fear of retribution, but I think a bigger reason is that “string theory” has become such a complex topic that few people (even few string theorists…) feel comfortable making any broad statements about its problems.

    I’ve found it highly problematic over the years that when journalists talk to me, and ask: “OK, you seem to make sense, but name a bunch of other theorists who we can talk to who agree with you about the overhype problem”, there are few people I can send them to. Matt believes that it’s an atrocity that journalists quote me since I don’t have the right credentials. At least now, since he’s “the chief US theorist” in the media, and is willing to acknowledge the overhype problem, that should help. Having others say something publicly would help too.

    At least in the US, the problem of string theory influence has changed a bit. Few places (except Princeton) will hire string theorists at the tenure-track level, with physics departments well aware of the overhype problem. But the top institutions are still largely filled with senior string theorists, providing few opportunities for the best students to get trained in other areas. These same people also have outsized influence on grants, prizes, etc., with the new money from Milner just exacerbating that problem.

  12. anon. says:

    APP, can you provide links to the limits you’re quoting? The latest CMS search for RPV gluinos in 3-jet resonances (through the UDD operator), for instance, is setting a limit below 500 GeV on the gluino mass. I imagine limits are stronger for the lepton-number violating processes, but I don’t know where to find the strong bounds you’re quoting. In the hadronic case I’m also not aware of a search for, e.g. gluino -> neutralino with the neutralino decaying to a 3-jet resonance through UDD. I was under the impression that most of the RPV parameter space is not constrained — or at least, not directly constrained in quoted limits, but maybe constrained by theorists’ re-analysis of the data. I would be happy to be corrected, though….

  13. Bob Jones says:

    “Few places (except Princeton) will hire string theorists at the tenure-track level, with physics departments well aware of the overhype problem.”

    I don’t know much about the job situation in physics, but this statement seems wrong to me. The work on amplitudes and twistor string theory is currently one of the hottest topics in theoretical physics. Over at the University of Chicago, a string theorist was recently given the position of “university professor”:

    http://news.uchicago.edu/article/2012/08/08/physics-initiative-launches-hiring-dam-thanh-son

  14. Peter Woit says:

    Bob Jones,

    The tenure-track particle theory job market is well-covered by the Rumor Mill at

    http://particle.physics.ucdavis.edu/rumor/doku.php

    This year the only string theorist I see getting a job offer is Simone Gombi at Princeton.

    The “amplitudes” business is not string theory and with rare exceptions the experts in it are not string theorists. People are making progress in computing QFT amplitudes, which are not string amplitudes. In some cases they have gotten some inspiration from techniques and calculations in string theory. Matt Strassler’s post telling the story is specifically, as he explains, trying to highlight cases of influence from string theory (although you’ll see in the comments, an expert takes him to task for this). The “twistor string” business is a small part of this story, although twistors themselves are a big part. But twistors really have nothing to do with strings: it was Roger Penrose who developed them as good variables for handling questions of 4d conformal invariance in GR.

    While string theorists are not getting hired at the crucial tenure-track level, the generation that got tenure in the late eighties or so is very heavily loaded with string theorists, since you almost had to be doing that to get a job at the time. These are now old enough to be the grand old men and university professors of the field, with honors and prizes of all sorts coming their way as they get to the right age. This doesn’t mean their non-string theory colleagues think that what they do has much future….

  15. APP says:

    anon: As I’m sure you know extracting the limits on RPV SUSY is a complicated business as there are so many parameters, one must be careful to impose all the flavor constraints on the RPV couplings/sparticle masses, and the final states (and whether they pass experimental cuts) are highly spectrum dependent. The limits I quoted are for CMSSM+RPV, so not 2 new things going on at once, in particular NOT also a “natural SUSY”/”effective SUSY” spectrum where all the superpartners not directly tied to electroweak symmetry breaking are made heavy. There are also certain assumptions on the RPV couplings that dominate motivated by flavor considerations, and most importantly NOT involving the UDD operator that you correctly mention as an exception (which is dealt with in the most challenging “natural SUSY” case by Raman Sundrum etal in http://arxiv.org/abs/arXiv:1206.2353 and which has significantly lower limits). In any case the limits can be extracted from the early figures of the Peter Graham etal paper I quoted together with ATLAS note http://cdsweb.cern.ch/record/1472934 (also useful to look at is https://cdsweb.cern.ch/record/1432202). Both Raman’s and Peter’s papers investigate tricky cases where RPV SUSY can be hiding, but as I’m sure you appreciate my point was that “vanilla” RPV doesn’t help much in weakening the sparticle mass limits and more complicated/clever things must be going on to have a SUSY spectrum without large fine-tuning. Hope this helps.

  16. Bob Jones says:

    “The ‘amplitudes’ business is not string theory”

    This is why the whole argument against string theory seems silly to me. In order to say that string theory has ruined theoretical physics, you take an extremely narrow view of the subject. You’re saying that the study of N=4 SYM amplitudes is not string theory even though it is equivalent to string theory by duality.

    “with rare exceptions the experts in it are not string theorists”

    I am not an expert myself, but I believe that many of the experts do conduct research in string theory (examples that come to mind are Arkani-Hamed, Bourjaily, Cachazo, Elvang, and Volovich). Many of these people are very young and have gotten tenure-track jobs within the last ten years.

    “the generation that got tenure in the late eighties or so is very heavily loaded with string theorists… These are now old enough to be the grand old men and university professors”

    Dam Thanh Son is actually a pretty young guy; it looks like he got his tenure-track job at Columbia in 1999.

    “This doesn’t mean their non-string theory colleagues think that what they do has much future…”

    Just look at the article I posted for evidence that this is not the case.

  17. APP says:

    Peter,

    I agree that many tenured theorists privately share, in whole or in part, your views. The problem with going public, and I can only speak for myself, is that I don’t want to become a public figure. I went into physics for the fun/excitement and privilege of research itself and I want to devote as much time to that as possible–I know that may come across as selfish but I don’t even like going to conferences if I can avoid them (even if they are in exotic locales)! Even more importantly I’m very disturbed how uncivil the atmosphere and nature of the discussion typically is in the press/blogsphere (very often not driven by the correspondents themselves, but by troll comments or by certain unsympathetic reporters wanting a personalized, and hence “dramatic” conflict). As I’m sure you appreciate very well it is hard to have one’s nuanced position not misreported or distorted out of all recognition, and even more upsetting, in a way that makes it seem like a personal attack. I’m sure we share the greatest respect for the achievements, intellect, and seriousness of the leading string theorists, and I think it would be wrong, and in the end counter-productive to allow opinions to be misrepresenated as personal attacks on them of their research. (Personally I feel that research is such a crazy thing to which to devote one’s life, the only real criterion is whether it makes the person him/herself happy! The rest of us don’t have the right to judge what a person does with their time—especially as the old Hollywood dictum “Nobody knows anything” is almost certainly right.) The primary issue that bothers me is that many very bright young students go into strings with a fantasy of what it’s going to be like and what they will work on and achieve, when in fact they would have been far happier and more productive with physics that is closer to experiment. It’s sad to see young talent and enthusiasm misdirected…

    Anyway, I’m sure you know my real-life identity, and I guess I’m OK for you to tell journalists that I’m one of the many (I could probably name a hundred other theorists) who have not too dissimilar views to you, but unfortunately my name is off the record . Sorry. Anyhow, Glashow, Georgi, & Wilczek are rather more substantial figures that would also support a sensible re-balancing of the field.

  18. piscator says:

    Dam Son is not a string theorist. Look at his publication history and what he has worked on. He is a field theorist who has, at times, used ideas coming from string theory.

  19. Peter Woit says:

    Bob Jones,

    I should have looked more carefully and seen who this was about, I just assumed it was a Chicago string theorist you were talking about. Yes, Son is of a later generation, he’s also (as piscator points out) not a string theorist, not even an HEP theorist (he’s a nuclear physics theorist, which is somewhat different). I’m sure some of the connection of his work with AdS/CFT gets him support from string theorists, but I’d guess the desire to hire and reward him has a lot to do with universities wanting to hire outside HEP and outside string theory.

    My argument with string theory has always been with it as an idea about unification, and I continually repeat that to make it clear. The relationship between string theory ideas and N=4 SYM is an extremely complex subject, my comments earlier were specifically about perturbative amplitudes and Witten’s twistor string. I don’t see any point to highly oversimplified claims about N=4 SYM and string theory being the same thing. That’s neither an accurate nor an interesting statement.

  20. huh? says:

    Just to keep things accurate here: you have repeatedly attacked attempts to connect string theory to nuclear physics or condensed matter physics as vastly over-hyped. Son, a virtuoso field theorist and many-body theorist, is certainly by far best known for his work on the holographic viscosity bound and related connections of holography to nuclear physics. His other most famous papers are on holographic models of QCD. Your last post is not accurately portraying your previous descriptions of string-related work, and the opinions of excellent physics departments (including evidently Chicago’s) are in genuine opposition to your own, regardless of what you choose to state on your blog. This has been reflected in hiring in the past, and will likely continue to be in the future. (I personally know of several top 10 physics departments on the lookout for promising young faculty who work in string theory or cognate areas with high overlap).

  21. Peter Woit says:

    APP,

    I understand your feelings pretty well I think. One of my motivations for getting involved in this is that I’m in an unusual position in a math department, in a position such that I don’t need to worry about grants and about a lot of things most people have to worry about. I’m well aware of this, and it’s one reason I thought I should speak up publicly, since I could do so without worrying about a lot of the things other people would have to. I hope the blog and the book provide a resource for students to hear a different point of view than they might otherwise get, giving them something to think about. A lot of the hostility I find rather bizarre: I have plenty of friends who are string theorists and have never had trouble discussing the subject, about which we almost always agree on much more than we disagree. On the few occasions people have invited me to “debate” a string theorist, they have ended up sorely disappointed by the lack of fireworks.

  22. APP says:

    Bob Jones,

    I know Dam Son somewhat and he would certainly not describe himself, or be described by others even in outside fields like condensed matter theory, as a string theorist. He’s a very sharp and creative quantum field theorist who happens to sometimes use string techniques, especially AdS/CFT, to answer interesting questions about strongly-coupled theories in certain limits. His collaborators are a bit closer to paid-up string theorists. Overall I think that Peter is correct in saying that the vast majority of tenure-track jobs nowadays are going to Standard Model/beyond-the-SM/astro-particle theorists. Also many of the best people working in the amplitudes field would not at all fit inside traditional string theory, Nima included. Never trust the blurb written by university administrators, or publishers’ PR departments to judge what people do!

  23. Peter Woit says:

    huh?

    Yes, I’ve definitely written about how string theorists have engaged in outrageous hype about the connections between string theory and serious work in nuclear physics, QCD and heavy ion physics, work of people like Son. Son himself has never engaged in this sort of hype from what I have seen, which is one reason people want to hire him, and not string theorists. As for your claims about departments wanting to hire string theorists, you should keep in mind that it looks like you’re at the one department in the world people think of as more fanatical about the subject than Princeton. We’ll see what the rumor mill says in coming years, the number of string theorists getting jobs in the US pretty much has to go up, it can’t get any lower.

    I suspect that you’re thinking of the condensed matter theory area of active research supposedly overlapping with string theory. Sure, as with Son, many departments would love to hire a good condensed matter theorist who has done AdS/CFT-related research that has had some success. Few however are going to be interested in people trained as string theorists who have moved on from overhype about its importance for particle theory and cosmology to now make overhyped claims about its importance in condensed matter theory.

    If string theorists retool themselves, become experts in another field, and make real advances in that field using some tools they learned as string theorists, that’s great. If they keep generating outrageous hype about string theory unification, the multiverse, etc, and try to justify themselves with dubious claims about how important their ideas are for other fields, they’re not going to get far.

  24. APP says:

    Peter,

    I also find a lot of (all?) the hostility bizarre. I really wish everyone took others’ views more seriously and less personally. Theorists and their groupies are, more so than the average, an arrogant bunch of people with fragile egos!

  25. anon. says:

    Thanks, APP, I hadn’t followed the details of applications of multilepton searches to bounding RPV parameter space. I guess we can summarize it as part of the bigger picture that the only allowed way to hide new strongly produced particles below a TeV is if they decay to multiple jets with very little missing energy and not many leptons or photons in the final state….

  26. APP says:

    anon,

    yes that’s my understanding too. glad to be of help—good luck in your research!

  27. Bob Jones says:

    “He is a field theorist who has, at times, used ideas coming from string theory.”

    “He’s a very sharp and creative quantum field theorist who happens to sometimes use string techniques”

    If you want to call him a field theorist and not a string theorist, that’s a terminological point and not a substantive one. I understand that Son does not work on string theory for its own sake, but his most famous work is on applications of string theory. I see no problem with calling such a person a string theorist.

    I think there’s a pretty good mathematical analogy here. Let’s say you have a mathematician who works in algebraic geometry and uses schemes to prove interesting results on algebraic varieties. Is this person a classical algebraic geometer or a modern algebraic geometer? I think most mathematicians would agree that this is a silly question.

    “My argument with string theory has always been with it as an idea about unification, and I continually repeat that to make it clear.”

    I realize this, and I actually agree with a lot of the points you make. But honestly, I find it strange that this is being framed as a debate over the legitimacy of string theory. The term “string theory” is a broad, ill-defined thing with lots of different connotations, and you really ought to use different terminology. Instead of string theory, why don’t we just say “multiverse” or “landscape” or “string phenomenology”?

    “I don’t see any point to highly oversimplified claims about N=4 SYM and string theory being the same thing.”

    I agree that I’m oversimplifying, but the point is that you can’t really separate string theory from quantum field theory. The two frameworks are so inextricably related that it’s hard to say what counts as string theory and what doesn’t. Again, I think the mathematical analogy is a good one. Saying you can do quantum field theory without string theory is like saying you can do algebraic geometry without schemes. Sure you can do it, but string theory is a natural extension of quantum field theory in the same way that the notion of a scheme is a natural extension of the notion of a variety.

  28. Sam says:

    There is a huge difference as to whether one is a “consumer” of the results of a particular field versus a “producer” of results in the field. For instance, in some of my research I have used extant “off the shelf” results concerning elliptic operators to answer certain questions in geometry. I am a geometer, but in no way would I consider myself, based on this line of research, an analyst.

    A more substantive discussion of whether one is a “string theorist” could be based on whether the person in question is actually producing new results in string theory. One can of course simultaneously be both a consumer and a producer of a particular theory. Has Son’s work produced new techniques, insights, results in string theory proper (beyond the insight that its methods can be used in the manner to which he used them?) The research can be great regardless of an answer of “yes” or “no”.

    But finally, it is odd to argue as to what category another person’s research belongs. I realize hobby horses need to be ridden here, but at the end of it all it is only the person in question whose opinion matters and it is likely that they don’t really have an opinion- they are just busy prosecuting their research.

  29. Peter Woit says:

    Bob Jones,

    Actually, the distinction between QFT and string theory is not just a terminological one. For one thing, we know what QFT is, whereas “string theory” is not a well-defined term (which is one problem with your string theory = schemes analogy).

    The campaign to make Son a string theorist and all quantum field theories string theories is an ideological one, basically an attempt to define away the problem of the failure of the main string theory research program. Better to keep different words for different things, as well as keep track of what ideas work and which ones don’t.

  30. Bernhard says:

    Seiberg’s prophecy fulfilled

    ““Most string theorists are very arrogant,” says Seiberg with a smile. “If there is something [beyond string theory], we will call it string theory.”

    (http://www.guardian.co.uk/science/2005/jan/20/science.research )

  31. piscator says:

    Bob Jones:

    The way I see it is more as follows. As I work on string compactifications I use various results on Calabi-Yau manifolds in my work. However by no reasonable classification am I a mathematician or an algebraic geometer.

    I agree that terminology is just terminology. However I think it begins to matter when encountering statements like ‘string theory has dominated hiring’, ‘there are too far many string theorists around’ etc. The way to support this statement is classifying everyone who was worked on anything related to string theory as a string theorist. You can do this, but it is misleading, as in most cases people work on string theory because they want to learn about some particular problem and string theory provides tools to address this problem.

    >>The campaign to make Son a string theorist and all quantum field theories string >>theories is an ideological one, basically an attempt to define away the problem of the >>failure of the main string theory research program.

    It is statements like this that make terminology important. If the `main string theory research program’ means a program involving particle physics-susy-unification-strings
    I can think of a total of one, possibly two, faculty hires in total in the US in this area in the last ten years. There are not that many people in the US doing this and, really, there never have been.

  32. Bob Jones says:

    “we know what QFT is, whereas ‘string theory’ is not a well-defined term (which is one problem with your string theory = schemes analogy).”

    You make a very interesting point here, but of course perturbative string theory is a fairly well-defined thing which can be formulated without reference to a dual QFT.

    “I agree that terminology is just terminology. However I think it begins to matter when encountering statements like ‘string theory has dominated hiring’”

    I guess I’m just not sure what point was being made. If the point is that people are not getting hired to do string theory and particle physics, then I agree. If the point is that string theory is dying/becoming irrelevant, then I disagree for the reasons I gave.

  33. Peter Woit says:

    Bob Jones,

    Yes perturbative string theory is a well-defined structure. But it’s not a QFT, and QFTs are definitely not perturbative string theory.

  34. anon says:

    Hi Guys,

    I was reading your comments about RpV in SUSY and I would like to mention a talk by Pavel Fileviez Perez about R-parity Violation at SUSY2012. It looks like there are well-motivated theories where one can expects RpV in a nice way. See:

    http://www.phy.pku.edu.cn/~susy2012/resources/conf_day3/plenary/4_Pavel-Fileviez-Perez-SUSY2012.pdf

    what do you think?

  35. anon says:

    A comment about G. Kane. I do not understand why him can be invited to major conference such as SUSY2012, his work is affecting the reputation of high energy physics, he should retire and allow a young person to get his place at UMich. Most of the people disagree with his papers, but since he is a political figure still the people invite him. There are no opportunities to young people and he is going around talking about these stupid results.

  36. Roger says:

    anon
    A scientist should never be forced to step down because others disagree with his papers. The tenure system (such as it is these days) is properly designed to support academic freedom.

    I’m certainly no supporter of Kane’s ideas btw.

  37. Mitchell Porter says:

    anon, Gordon Kane isn’t a one-man show. There might be a dozen or more people working on M-theory phenomenology in that general framework (G2-MSSM). It’s actually one of the more bold and interesting things I can see going on in phenomenology, because it does try to make connections to fundamental theory, and I don’t blame Kane for being excited that he can get a 125 GeV Higgs, 145 GeV dark matter particle, and so on, without finetuning.

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