Several things have come up recently that brought up the year 1985, the year the film “Back to the Future” came out.
This summer the IAS will be running a two-week program at the IAS on Strings and Phenomenology, designed to train a new generation of graduate students and postdocs in the details of compactification methods which mostly go back to 1985, quite possibly before some of the attendees were even born. No evidence that there will be any mention of the fact that 23 years of work on these topics has led simply to a dead-end: the landscape.
At SUSYO8, the first two speakers harkened back to the 1985 period, with Hans Peter Nilles (who also will be lecturing at Princeton) quoting his own words from 1984 (Physics Reports 110):
Experiments within the next five to ten years will enable us to decide whether supersymmetry at the weak interaction scale is a myth or reality
He notes that “This statement is still true today!”
Andrei Linde in his talk on cosmology crows about what he sees as Witten’s recent capitulation to the anthropic landscape point of view about string theory that Linde was pushing back around 1985 (actually 1986) when he wrote:
An enormously large number of possible types of compactification which exist e.g. in the theories of superstrings should be considered not as a difficulty but as a virtue of these theories, since it increases the probability of mini-universes in which life of our type may appear.
which he compares to this from the New York Times
Now, Dr. Witten allowed, dark energy might have transformed this fecundity from a vice into a virtue, a way to generate universes where you can find any cosmological constant you want. We just live in one where life is possible, just as fish only live in water.
At the same time, I’ve been reading and thinking about some papers written back in 1985 which deal with the mathematics of gauge theory and anomalies. At least some of these were never published, including one that I’ve seen references to (by Igor Frenkel and Iz Singer), but never a copy of (does anyone have a copy?). Looking at the history of this subject, it is clear that some very good people were working on this until 1985, at which point quite a few of them dropped it to take up the new fashion of string theory.
Perhaps the LHC will revive the subject of particle theory, by producing a wormhole that will take the world back to its other end, opened up in 1985 by a DeLorean in the movie, from there setting us off into a more promising part of the multiverse.
>At the same time, I’ve been reading and thinking about some papers written back in 1985 which the mathematics of gauge theory and anomalies.
Is this a valid english sentence?
roland,
No, it’s not, but now I’ve fixed it. My proof-reading is not all it should be. Thanks for helping.
It is sad to see people rehashing what they were saying in 1985. Compactification is too simple minded. I’m surprised that supersmart people like Witten are still into that.
Peter, you refer to “… the mathematics of gauge theory and anomalies. At least some of these were never published, including one that I’ve seen references to (by Igor Frenkel and Iz Singer) …”.
Is that work related to what Alex Jay Feingold describes
on his CV page at SUNY Binghamton?
There, he says:
“… During the period from 1981 to 1991 I had several collaborations with Igor Frenkel (Yale University) … with J. F. X. Ries … Our main objectives were to obtain independent vertex and spinor constructions of chiral algebras,
the isomorphism between the two viewpoints,
known as a “boson-fermion correspondence'”,
and constructions of the exceptional affine algebra E8(1) based on D4(1) spinor constructions and the principle of triality. …
Some of these results were announced at the 1988 Conference on Lie Algebras and Related Topics, Madison, Wisconsin.
Those results which only involve the spinor constructions are in our Contemporary Mathematics monograph …
A sequel (with Ries only) was planned to give the vertex picture and the boson-fermion correspondence,
but the untimely death of Ries has substantially delayed the completion of that project …”.
Do you know of any available publication in detail of that Feingold-Ries work involving “the vertex picture and the boson-fermion correspondence”?
It seems to me that such a Feingold-Ries project might be related to, and improve on, the E8 model of Garrett Lisi,
and
be a way that “respectable” math/physics people could work on such stuff.
Tony Smith
mathphys,
I don’t know what Witten will be talking about, but the strange thing about this whole subject is that the circa 1985 ideas about compactification are still in some sense the most aesthetically convincing ones. Since then, attempts to do better have pretty much all led to much more complicated and ugly constructions. So, I can see why someone asked to talk about this subject might want to talk about the 1985 version. Some of the other lecturers will be talking about more these more recent ideas. and trying to lead the students into the landscape…
Tony,
That’s a different subject. I don’t know anything about the unfinished Feingold-Ries work, but it sounds like it’s closely related to the Feingold-Frenkel work on spinor constructions of vertex algebras, which has been published (although I don’t know much about that literature).
The paper I have in mind is about the Hamiltonian approach to the gauge anomaly in 3+1 dimensions.
Has it been that long? Incredible. However, I quite like this timeline, thanks. I do not want some Biff Tannen-style physics 🙂
I see this more as a “Terminator” scenario than a “Back to the Future” one. The dominance of String Theory was intended by our time-travelling descendants as it has prevented discoveries in fundamental physics (you know – real physics: remember that?) that would have been dangerous to society.
We will know this for sure if Peter suddenly finds himself pursued by a Killer Robot from The Future (or maybe this is already happening)
“Experiments within the next five to ten years will enable us to decide whether supersymmetry at the weak interaction scale is a myth or reality
He notes that “This statement is still true today!””
This is very true and in a sense is a specific effect of the cancellation of the Superconducting Super-Collider. You could say that it cost a generation of physics advancement in particle physics. We would have had answers to a lot of things and a lot more data to eliminate ideas with.
We are becoming like the mid 80’s again in that sense: We again (an for real this time we hope) are just before looking at new information about a new level of energy in particle collisions.
Markk,
I agree that the SSC cancellation has set things back a generation, but this isn’t relevant to the Nilles quote. He made it back in 1984, and was explicitly claiming that SSYM would be seen by the time you got to a 100 Gev scale, i.e. he was talking about the Tevatron, not the SSC. The SSC project was not even approved until 1987 (canceled in late 1993), so couldn’t have been what Nilles had in mind when he wrote that SSYM would be seen in “5-10” years from 1984. Even under the most optimistic assumptions, there was no way that in 1984 one would think that the SSC would be built and operating in 1989-1994.
It isn’t hard to find quotes from the 80s about how SSYM was definitely going to show up at the Tevatron, it is only in the 90s as it became clear this wasn’t happening that the assumed scale of SSYM got moved up from 100 Gev to the “Terascale”.
“…quoting his own words from 1984 (Physics Reports 110):
Experiments within the next five to ten years will enable us to decide whether supersymmetry at the weak interaction scale is a myth or reality
He notes that “This statement is still true today!””
A good example of someone whose timeline/logic/truth interfaces need adjusting
My interpretation of that quote was quite similar to Markk’s, actually. I think a lot of people would tend to read the quote that way. The fact that the original text was referring to the TeVatron and not the SSC completely changes the context. In fact, it makes this post much more interesting.
I think quoting one or two more of those would do a lot to strengthen your point.
wilbur,
OK, here’s one more:
Haber and Kane, Physics Reports 117 (written in 1984)
pg. 82
“While there is no compelling supersymmetric model, all the ones studied produce some detectable superpatrners that are light, often with masses well below m_W. More technically, the models can be tuned to have a larger scale of supersymmetry breaking and still account for m_W at tree level, with no partners below m_W,but then they are unstable and have to be retuned as soon as radiative corrections are included. Models where such radiative corrections are less than the masses themselves have detectable, light superpartners.”
pg. 89
“Finally, we note that it is not a problem for supersymmetric ideas that superpartners have not yet been found. As we will discuss in chapter 9, most of them are expected to have masses of order m_W,and could not have been detected yet. Those that could have been observed, such as the gluino, are allowed to be heavy enough to have been unobservable so far. But as we will see, the machines available in the next decade will have a high probability of detecting supersymmetric partners if supersymmetry is relevant to understanding the weak scale.”
“Machines available in the next decade” clearly refers to the Tevatron, LEP and HERA, this is also clear from the argument about m_W.
thanks for the quotes. Fascinating stuff, looks like a time tunnel. In summary, if the LHC doesn’t find susy, the HHC probably will.
wilbur,
It’s very, very easy to find quotes from the 80’s of the type that you want to see. Peter Woit gave the simplest examples, but trust me, the literature is full of them. I only want to see/hear/read anyone of these guys own up and say “In about 50 papers that I wrote in the 80’s and 90’s, I made predictions that now I know were simply totally wrong. Now let me start all over again”. But no, they always carry on as if they were always on the right track and things are progressing linearly. And they call themselves scientists.
In my department there are some great “LOLCat”-style posters with an image of a black hole and the caption “Im in ur LHC, eatin ur universe”. The posters announce a light-hearted debate of the graduate students in the Physics and Astronomy department on July 11th with the following premise: if a relativistic heavy ion experiment at the particle physicists’ accelerator produces black holes, which group of physicists should be liable for the damage 🙂
Actually I remember the times of which you speak very well. We all got very excited about the fact that gauge fields were connections on principal fibre bundles. Just when it was dawning on us all that this line of research was leading absolutely nowhere, Witten came along and saved the day. I can assure you that the times for which you hanker were even worse than now, and that ”not even wrong” applies far more convincingly to the things you favour than to string theory.
hidalgo,
Funny, I remember those time quite well myself. The mood among particle theorists was rather different than it is now, I wouldn’t exactly describe it as “even worse” though….
>It’s very, very easy to find quotes from the 80’s of the type that
> you want to see. Peter Woit gave the simplest examples, but
> trust me, the literature is full of them. I only want to
> see/hear/read anyone of these guys own up and say “In about
> 50 papers that I wrote in the 80’s and 90’s, I made predictions
> that now I know were simply totally wrong.
To me the sarcastic way in which Nilles was referring to his own quote is precisely that. I completely fail to see in what sense Nilles is supposed to “apologize”. Wrong ideas are merely left by the wayside in science and not held to court, and thats what happened to the guess about the exact energy scale of new physics (actually the general prediction for the energy scales, that it is around TeV, might still be right).
People were hoping back then that something would be seen close to TeV, and that hope is still there. The EXACT energy scale is what the bets were made about (and lost). In fact, I am certain that many people on this thread know this, and are actively ignoring it because it is conveneinet for their agenda.
Nilles was certainly “wrong” in that sense. But contrary to your subtle implication, nobody (including him) claims today that they were right back then in that narrow sense. Of course, many of them still believe that TeV scale susy is a possibility, but thats based on scientific judgement, and because we don’t seem to have any better ideas.
In any event, being wrong is hardly an isolated event in physics. It comes with the territory of “trying”. The “hindsight is 20-20” type talk has only one purpose and that purpose has nothing to do with science. Incidentally, let me just point out one obvious thing because the discussion here has taken a condescending air: it is clearly an easier task to sneer at people who try, than to try oneself.
> Now let me start all over again”. But no, they always carry on as
> if they were always on the right track and things are
> progressing linearly. And they call themselves scientists.
Thats only because we (not “they”) still don’t have any reason to believe that we were qualitatively wrong back then. The hope is still that around TeV is where the action is – if anybody has any better ideas they would of course be welcome, but the fact of the matter is, as it stands we don’t. In fact, we could still be wrong, and ten years later some others like you might mock us. But that possibility is totally useless in deciding how we do science now.
The ONLY thing that can save us from mediocre ideas is a great idea: not personal attacks and uncreative criticism.
Somebody,
No, people in 1984 were not expecting to see SSYM breaking at 1 TeV, they were expecting to see it at 100 Gev. The Haber/Kane quote that I reproduced explains precisely why (you have to do some fine-tuning to avoid superpartners below m_W).
The fact that SSYM was expected to show up, didn’t, and now requires fine-tuning to explain why it hasn’t been seen is something that its proponents don’t ever mention. Some readers here didn’t seem to originally believe me that this is the case.
Let me point out that I am not engaging in personal attacks on Nilles or anyone else. I do think though that this particular bit of history, failed prediction of SSYM, and required fine-tuning is something that deserves to be better known to anybody who wants a clear idea of the prospects for seeing SSYM at the LHC.
Peter,
The MSSM only requires that the superpartners be in the 1 TeV range in order to solve the hierarchy problem. This requires no fine-tuning. It is only now with the LHC that the full parameter space can be explored. Back in the eighties, they were only beginning to probe the lowest energies of where one might expect to find the superpartners. So, some of them were overly optimistic. So what? This was also true in regards to the top quark.
SUSY always had problems – it did then, and it does now. But the balance of evils seemed somewhat in its favor back then, and it still does.
The books and reviews on phenomenological susy invariably leave you with the impression that there are plenty of things that are NOT pretty about it. Every fine tuning that you can possibly talk about, from higgs mass to susy flavor problem are all discussed in the textbooks. So I totally fail to see in what sense you are suggesting that the fine tunings are not well-known. The scientific facts are entirely well-known. The only thing missing from the textbooks is the personal attacks.
About your claim that we were expecting to see susy at 100 GeV: you are ignoring what I emphasized in my previous post, that the PRECISE scale was where the “predictions” went wrong. If you want to split hair at the 10% level, there are actually even worse problems. Eg: the mu-problem which requires not 10% level fine tunings, but 1% level fine-tunings. The existence of fine-tunings is a fact about susy, but the fact still remains that it is still pretty much the best idea we have. So any attacks of this kind about our past follies (without any suggestion for a better idea) accpomplish absolutely nothing.
I am actually charmed by the disarming honesty with Nilles pointed out one of his own old “wrong” predictions. It would be nice if we had radically new predictions now, but unfortunately we don’t.
Supersymmetry only requires finetuning (of the Stop) if various eventualities occur.
1) The mass of the Higgs cannot be too heavy. Its best if its right around 115-120, at least for the MSSM
2) Refinements in the top quark mass have moved around in the previous decades, which also affects things.
How much finetuning you are willing to accept is a bit of an aesthetic requirement. We’ve seen finetuning in nuclear physics up to about 2 orders of magnitude before, so it shouldn’t surprise people if there is a little bit. Its when you start talking about 16++ orders where people start really wondering if we’ve gone insane.
Its true that the minimal ‘bayesian’ models from the 80s of phenomenology would have arranged the masses a little bit differently. We should have seen a lighter Higgs, a different top mass, and some SuSY already on those grounds, but nature doesn’t always pick the simplest solution either (see the expanding universe).
After the LHC, if we still haven’t seen SuSy, the original premise is gone and it might juts become something quantum gravity people are interested in, and not day to day phenomenologists. Still i’d say theres still a good percent chance that we will see weak scale SuSy (I’d give it a good oh.. 1 in 3 chance, which is much better than any alternative).
Peter,
Witten talked about the work of Vafa et al on how to embed GUTs into F-theory. Not quite the stuff of 25 years ago. There is a lot more hope of uniqueness in this picture than in the flux compactifications.
invcit: what is ‘F-theory’?
(Sorry Peter if this question sounds off-topic, hostile, and adding noise, but I genuinely don’t know what F-theory is!)
Wikipedia has an answer:
http://en.wikipedia.org/wiki/F-theory
“F-theory is a branch of string theory developed by Cumrun Vafa. The new vacua described as F-theory were discovered by Vafa, and it also allowed string theorists to construct new realistic vacua — in the form of F-theory compactified on elliptically fibered Calabi-Yau four-folds. The letter “F” stands for “Father” much like the “M” in M-theory is often taken to stand for “Mother”.”
Thanks, Arun. I had seen a post on this blog some time back about the experimental predictions of F-theory:
http://www.math.columbia.edu/~woit/wordpress/?p=697
but I didn’t understand F-theory. There is a nice paper on ‘Evidence for F-theory’ by Vafa on arxiv: http://arxiv.org/abs/hep-th/9602022 The math isn’t really hard.