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.