At the big annual APS meeting, now going on in Jacksonville, of the 9 plenary talks, one is about particle theory. The talk is entitled “String Theory, Branes and if You Wish, the Anthropic Principle” and it was given by Shamit Kachru of the Stanford group. Here’s the abstract, which besides the usual claims that string theory is “our most promising framework for a unified theory of the fundamental interactions” and that “the underlying theory is unique”, also makes the claim to have “testable ideas about inflation and particle physics”. No clue what these ideas are, so I don’t know if they include the testable prediction the landscape makes about the proton lifetime. Also unclear why the Anthropic Principle is being demoted to “if You Wish”. Lots of experimental talks on particle physics at the conference, here’s a Fermilab press release on CDF and D0 results discussed at the meeting. Lawrence Krauss was speaking on “Selling Physics to Unwilling Buyers”, I wonder what that was about. More about the meeting at the Physics Meetings blog.
David Ben-Zvi has put up on his web-site his lecture notes from last week’s series of lectures in Oxford on geometric Langlands. As usual, a very readable survey of the subject, emphasizing links to representation theory.
For another source of material about representation theory and the (non-geometric) Langlands program, see the web-site hosted by the Clay Mathematics Institute devoted to the collected works of James Arthur.
There’s yet another round of discussion on bloggingheads.tv between science writers John Horgan and George Johnson. This week the LHC and the state of particle physics are some of the topics they consider.
From Fermilab, various new sources for discussion of the future of experimental particle physics include:
A web-site for the steering group tasked with developing a roadmap for future use of US accelerators. This week’s meeting includes a presentation on reconfiguring the Fermilab accelerator complex to produce larger numbers (factor of 3 more) protons, for use by neutrino experiments and others.
The Fermilab Physics Advisory Committee met on March 29-31, here are the presentations and report.
Last week there was a workshop devoted to considering what effect early data from the LHC would have on plans for the ILC (via Tommaso Dorigo).
Finally, Steven Miller, author of “String Kings”, has a new blog he is working on, devoted to essays on mathematical physics, theoretical biology and the history of science.
Update: Two more.
Seed magazine has a series of “cribsheets” about science. For physics, they cover nuclear power, the elements, and now string theory. The lack of predictivity of the theory is given a positive spin as being due to the “rich diversity” of string theory. At Cosmic Variance, Sean Carroll approvingly refers to this as “it only refers glancingly to the anthropic principle, which is a much more accurate view of the state of discussion about string theory than one would get by reading blogs.”
Nature has an article about the state of the LHC and the possibility that the Tevatron might be the first to see the Higgs. LHC project manager says that they were already running about 5 weeks behind schedule before the problem with the quadrupoles appeared, but says “In my view the magnet problem has been blown out of proportion… It is a very small part of a bigger picture.” If the schedule slips much more, there might not be time for an engineering run in 2007, and the first science run might be delayed until later in 2008.
Update: Thanks to commenter F. for pointing to the slides from Kachru’s talk. It’s a clear presentation of the moduli stabilization problem and the techniques that he and others used to solve it, while at the same time making the landscape problem much worse. The “testable” ideas mentioned in his abstract are the usual sort of thing behind claims like this: not actual tests of string theory, but effects in certain very specific models among the infinite variety of ones you can get out of string theory. Kachru doesn’t much address the issue of whether the landscape framework is testable science in the conventional sense, other than to describe people’s attempts to use eternal inflation to explain how the vacuum gets selected and try and get physics out of this as “notoriously confusing.” He also describes counting of vacua as favoring high-scale supersymmetry breaking, so maybe there is a prediction: no supersymmetry at the LHC.
Update: For the latest from FNAL on the LHC magnet problems, see here.
Hm. Wikipedia:
I personally didn’t know most of the things in that article so I’m finding it kind of interesting; either way, though, whether we view the greek atoms as atoms or some other class of even more fundamental particle, it doesn’t appear that any versions of the atomic hypothesis that particularly resemble reality were proposed until Newton and Boyle. (Although the “hooks and barbs” idea, at least as Descartes formulated it after resurrecting the idea, seems to have a certain conceptual resemblance to valence electrons and shells).
So, E brought up the greek atomic theory as an analogy to String Theory, to observe that the greeks correctly postulated the atomic principle long before the ability to directly observe atoms was close to being available. Were I to try to make an analogy to String Theory here, it would be more to observe that even if the basic string hypothesis were someday found to be accurate, it could well be that every single other idea that today comprises String Theory is utterly wrong, just as the atomic hypothesis is right but the sensation of cold is not, as Democritus’ version of Atom Theory would lead us to conclude, caused by atoms with pointy ends.
Another possible analogy to string theory suggests itself if you ask the question of why the greeks were able to correctly hit on the idea of fundamental atoms/particles, but then get all of the details wrong. One possible answer to that question is that the greeks were, as far as I can tell, working off of purely philosophical methods, with no particular effort being made to follow the modern strategy of developing testable or falsifiable hypotheses. Without at least some effort or ability to check their progress against reality, they were unable to see when at some point or other they started off on a wrong track in a minor way (for example, assuming atoms took simple geometric shapes), and after following that wrong track to its logical conclusion wound up with a theory of matter which was “elegant” and self-consistent but unfortunately, with the technology of a couple thousand years later, is observably obvious as totally wrong. There is probably a similar trap waiting in the modern era for anyone who tries to do too much by purely mathematical methods and does not at some point start seriously asking the question of how to verify against experiment…
It would be interesting to check a more in-depth history of the atomic hypothesis to see exactly at what point the idea of experimental science first became explicitly involved in the formulation of atomic theory, and see whether this had an immediate impact on the ability of the theorizers to come close to the way atoms or fundamental particles actually work.
Coin,
I should point out that many scientists did not believe in the existence of atoms as late as the early 20th century. However, there were others, such as Boltzman, who used the concept of atoms to construct mathematical theories, e.g. statistical mechanics.
Dear Peter,
I would disagree with you that the progress in understanding nonperturbative aspects of string theory has made the situation worse. The ‘landscape’ has always been with us, despite Susskind. String theory is a deep theory with a rich structure. It may take a much longer time before we really understand it. Thus, I would say your criticisms are premature.
E: Right, but Boltzmann’s ideas– even if they were poorly accepted in their time– were not dependent on pure thought, philosophy or mathematics, but were fundamentally testable and falsifiable. Boltzmann’s ideas about statistical mechanics were mathematical, but the math was such that it could predict things which could then be tested, even with the limited technology of his day. There are things about the behavior of gases which Boltzmann’s mathematical theories based on the atomic model uniquely explain as an unambiguous consequence, and which mathematical theories based on other models of matter did not explain at all. In terms of process this is all quite different from or pre-Renniasance atomic theory or even modern String Theory.
E.
The “landscape” has not always been with us. What was with us before the landscape was the moduli stabilization problem, and the hope that non-perturbative effects would stabilize moduli and lead to only a small number of consistent vacua. Instead they led to the landscape in its incarnation as an exponentially large number of stabilized vacua.
Peter,
As I said, the problem of 10^{600} vacua has been with string theory from the beginning. The additional stabilized vacua via fluxes is just the same problem recast in a different form. In all probability, these vacua will turn out to be an artifact of our current perturbative formulation of string/M theory.
Coin,
Perhaps a better analogy would be to DNA. From a single object, a wide diversity of living creatures are possible, a landscape if you will.
An analogy from what to what? That just seems unrelated to anything in this thread so far.
Anyway, a random question on a totally different subject:
Peter Woit wrote:
What has to happen before the supersymmetry hypothesis can cease to be taken seriously by the scientific community entirely? My understanding is that supersymmetry is like proton decay– it can always avoid falsification by just tuning up the numbers. If an experiment fails to demonstrate proton decay, we can still say proton decay occurs but at a half-life so high the experiment wouldn’t have been able to detect it; if an experiment fails to demonstrate the existence of supersymmetric partners we can still say the partners exist but at a mass so high the experiment wouldn’t have been able to detect it.
However, there was a point where the lower bound on proton decay eventually got so high that people just stopped taking it seriously; I understand when we got to the current result of proton decay having minimum half-life 10^35 years, that was considered the same as demonstrating proton decay not to occur.
Does this same thing eventually happen to supersymmetry? While it would be great if they were found, if supersymmetric partners are not found by the LHC, will we start to assume they do not exist? What about the VLHC? What energy scale do we have to reach before physicists can no longer propose supersymmetric partners can still be found while keeping a straight face?
Coin,
I don’t think proton decay bounds are as good as you say, more like 10^33 at best. As far as I know, typical SUSY GUTs are not ruled out at this level. Typical non-SUSY GUTs are, and this caused people to lose interest in them. If you use the constraint of unifying couplings, that fixes the GUT scale, you can’t just move it up.
For supersymmetry, you can move up the breaking scale, but at some point you lose the ability to claim that SUSY stabilizes the electroweak breaking scale/Higgs mass. This is actually already in trouble, the current bounds mean a significant amount of fine-tuning is required. I think if the LHC doesn’t see supersymmetry, it will be hard to take seriously the idea of supersymmetry stabilizing the Higgs mass, but people may still keep claiming that the world is supersymmetric, just at unreachably high energies.
If you look at Tevatron predictions, you see a lot of people claiming that they were pretty sure the Tevatron would see SUSY. This failure didn’t slow them down much, but an LHC failure might.
Coin,
SUSY SU(5) has essentially been ruled out by the proton lifetime, however other SUSY GUT’s such as flipped SU(5), SO(10) and Pati-Salam are still viable. As Peter correctly points out, if SUSY is to solve the gauge hierarchy problem, then we expect TeV scale superpartner masses. If LHC doesn’t see SUSY, then we’re screwed. However, I don’t think this is very likely.
My earlier comment was making an analogy of strings to DNA. DNA is a fundamental object, but can lead to many possible solutions. In this way, it is like the landscape. Even though we know the structure of the DNA molecule, we don’t yet know how to predict exact features of the lifeform that would arise from this DNA. You could of course make a similiar analogy to atoms, which gives rise to a ‘landscape’ of molecules.
E., there is a little problem with your analogy: we can see cats and dogs and many animals and hydrogen and oxigen and many molecules, but I have never seen another universe. Can you post a picture of it?
Dear E,
You say, “LQG is interesting, but I don’t think it’s possible to construct gauge theories within its framework.” In fact, there are a number of papers showing how to incorporate gauge theories coupled to gravity in LQG, see for one example in spin foam models, 0207041. For the hamiltonian framework there are earlier papers, for example Thiemann’s papers which described coupling to gauge fields, fermions and scalars-and even earlier. There is also a literature about using LQG methods to study quantum Yang-Milsl theories, indeed the loop representation was first introduced by Gambini and Trias in this context, for the most recent work in this area see the recent papers of Florian Conrady. And before you ask, yes there are also papers on incorporating supergravity, in both path interagral and hamiltonian frameworks.
Please, could you be so kind in the future as to check the literature or check with someone in the field before making false statements.
Thanks,
Lee
ps as to how long the landscape has been with us, the earliest reference I know of to the issue of a vast number of equally consistent vacua is Strominger’s 1986 paper on Torsion in Superstring Theory. He makes a clear statement that there is a problem with predictability. But Peter is right that many experts claimed for years afterwards that moduli stabilization and susy breaking would lead to a unique and predictive ground state. Those few of us who argued otherwise were definitely in the minority.
Thanks for the link to the Jacksonville meeting.
Kachru’s talk is a nice review of some of the current
directions in string theory. The very informative
slides of the talk are here:
http://www.aps.org/meetings/multimedia/upload/kachru.pdf
Cheers, F.
Lee,
Thanks for the information on LQG. Has anyone been able to construct Standard-like models within this framework and can it make predictions for particle masses, gauge couplings, etc.? If not, then I’d like to see Peter et. al. hold it to the same standard that they hold string theory. From what I know, the main argument for LQG is that it is background independent, whereas string theory is supposedly not.
Lee,
Just a thought, but is it possible that LQG is equavalent to Matrix theory? The quantized area and volume of LQG seem to me to be very similar to D0 branes….
Here is a question I have:
any gauge theory may certainly be described by conceiving their configurations, which are bundles with connection, in terms of the corresponding holonomies. Smooth holonomy maps are equivalent to smooth bundles with connection.
In many (most?, all?) discussions in the context of LQG, people enlarge the configuration space from smooth holonomy maps to “generalized connections”, namely to holonomy maps which need neither be smooth, nor even continuous.
Doesn’t this step loose a lot of structure? For instance the possible nontriviality of the gauge bundles is lost (as every bundle in Set trivializes, as opposed to bundles in Top or in C^infty).
Isn’t much of the difficulty in LQG of making contact with what are called “semiclassical” structures ultimately due to this enlargement of configuration space?
Can one expect to capture Yang-Mills theory — even classically — when connections are replaced by “generalized connections”?
Finally: are you aware of the work by Freed-Moore-Segal? This is in spirit very close to the concerns of LQG, in that one studies configuration spaces of connections and their quantization, but stays within the context of smooth connections. (Difference is that they consider only abelian connections at the moment, but also for higher degree.)
They find interesting, and rather subtle, quantization effects. I doubt that any of these interesting structures would survive a passage from smooth to “generalized connections”.
Or is there an idea of how to recover information about smooth connections from information about “generalized connections”?
Urs,
This kind of technical discussion of LQG, while interesting, is completely off topic and not something I know know anything about. Unfortunately I can’t let this blog turn into a general discussion forum for whatever people are interested in, because I don’t have the time or energy to moderate such a thing. There are a small number of people in the world who can give you an informed answer to your question, I suggest you contact them directly.
Peter,
I would argue that string theory is also something that you’re not an expert on (how many papers have you written on the subject?), but that doesn’t stop you. LQG should be part of the discussion, since it’s one of the supposed alternatives to string theory. The question is, is LQQ also ‘not even wrong’ since it doesn’t make any predictions either?
E,
What is worse, not making any predictions after 2,000 man-years or not making any predictions after 20,000 man-years? If you put the bar at 10,000 man-years, it seems like funding to string theory to be nullified at once, whereas LQG has another 8,000 man-years to go.
Not that I believe much in LQG, but that’s another matter.
E.,
I have a Ph.D. in particle theory, and have spent a sizable fraction of my time during the last 23 years learning about string theory, following the subject closely, and discussing it with many experts. I’m quite comfortable that I know what I’m talking about when I criticize it. String theorists seem to often feel that the way to respond to my criticisms is, when their scientific arguments fall apart (e.g that Green-Schwarz proved that string theory is the only possible theory of quantum gravity), to try and attack my credentials and my right to speak on this topic. This tactic hasn’t worked for them so far; it’s kind of transparent that it’s what one does when one has lost a scientific argument.
I’ve spent a much, much smaller time learning about LQG, and, as you must know if you read this blog, my main interests are in particle theory and in mathematics, not in GR or in quantum gravity. I leave the arguments about whether LQG or string theory is a better theory of quantum gravity to others, and stick to what I know about, particle physics. As a purely sociological matter though, the main problem with string theory is the way it overwhelmingly dominates the formal end of particle theory research, despite its complete failure to tell us anything about particle theory beyond the standard model. By contrast, the amount of effort being devoted to LQG seems to me quite reasonable and healthy.
Peter and Thomas,
Don’t get me wrong, I have absolutely nothing against LQG. I merely make the point that it suffers from the same issues that you constantly ascribe to string theory, namely predictability. As for time and money allocation, if more people thought LQG gravity had the same potential as string theory, I’m sure that it would get more attention.
Peter: A quick check on Spires shows that you haven’t been an active researcher in nearly twenty years. At any rate, if you have legitimate arguments against string theory, write a paper on it and submit it to the arXiv and a peer-reviewed journal. That’s the proper place to have this debate, not in the public arena, where it is essentially just grand standing.
Peter wroite “it will be hard to take seriously the idea of supersymmetry stabilizing the Higgs mass, but people may still keep claiming that the world is supersymmetric, just at unreachably high energies.”
Would there be any credibility to this claim, that there is SUSY at unreachably high energies, should LHC not find SUSY? A major reason for accepting SUSY to begin with was stabilizing Higgs mass against radiative corrections. Another was that it would allow GR to be renormalizable.
E:
Peter can defend himself, but I am a lay person (retired engineer) and I have a valid legitimate argument against string theory: After 22-23 years ST has not made single quantitative connection with the real world, none, nada, zilch, nil. Got it! It is based on two premises that were and still have not been validity, i.e.., > 4 dimensions and supersymmetry. Why continue to pursue some theory that has no connection with the real world?? I cannot think of a single instance in physics research where this has occurred for 20 odd years can you??
Wow, E, you just totally lost this argument.
E.,
String is the mainstream theory, hogging the limelight. There’s no mention of LQG in the popular media. However, LQG certainly sticks closer to trying to model phenomena that can be observed. This should really be a paradox for all to worry about: why have people have lost faith in simplicity?
If Peter discusses LQG as well as string, that will be convenient to string theorists, who will be able to say he’s just against everything. This is the opposite of the facts, it seems, since the problem is that there needs to be more alternative ideas, not consensus on unchecked speculation like string.
String is unique – and thus singled out for criticism – because it is entirely based on unobservables and speculation of the uncheckable variety. Excuse unification problems and quantum gravity problems by introducing unobserved extra dimensions. Excuse the huge landscape of models resulting therefrom by using the anthropic principle. Excuses for speculative failures.
I wish we knew who E was – what I mean is his intellectual history. I’d like to know where E got the notion that Green and Schwarz proved in 1984 that ““String theory is the ONLY framework which allows one to combine quantum mechanics, gauge theory, and gravity in a consistent way”. Was it in a physics classroom? Seminar? Who was the speaker? etc.
______
On a different note, it seems to me that the Wilsonian teaching about renormalization was that a landscape of high energy theories would all lead to pretty much the same low energy effective theory; and now string theory is telling us that a landscape of low energy effective theories results from a single high energy theory. We cannot bootstrap ourselves from having to examine each energy scale experimentally; there is no point at which we know enough that physics can become axiomatic and deductive like mathematics.
____
It is interesting that E. questions Peter W.’s competency by
discussing his lack of publications in SPIRES. I wish people
who disagree with Peter would stop using this tactic, which
ultimately undermines whatever else they have to say.
So E:
1) Peter is a mathematician these days. So what if his papers
aren’t on SPIRES?
2) Can’t someone who is not working in an area be capable of
making an evaluation of that field? By necessity, we all have
to do this, to decide what to work on, or simply to maintain
perspective. We often look at ideas in high-energy
physics and classify them as useful or as dead ends, even if
we haven’t actually written papers on these ideas.
I’ll let E’s arguments speak for themselves, but I’ve often been hearing from string theorists his complaint that criticism of string theory outside a peer-reviewed scientific publication is somehow illegitimate.
I would have some sympathy for this were it not for the huge amount of pro-string hype produced for public consumption over the last twenty-some years: from magazine articles to books to TV and radio programs, etc., etc. Much of this material is highly misleading and gives a completely inaccurate picture of the state of string theory research, so much so that it leads to people like E. repeating exaggerated and bogus claims like the one about Greene-Schwarz. One reason for my book was to provide scientists and the public with the other side of this story. One can argue pro or con about whether conducting debate on this topic publicly is a good idea, but I don’t think one can argue that the earlier status quo, only pro-string hype allowed in public, was a healthy or honest situation. I know of a few string theorists who were privately unhappy with the public hype, no examples of any string theorists who publicly expressed any displeasure, until public criticism of the theory started to get attention.
It’s quite sad, that someone really spends time writing anti-string theory books and blogs, when he could be doing real research instead. So far, no one has a unified theory that works, but that does not mean one should not pursue the goal. But I admit: philosophising and nagging about problems is easier than doing the real work!
Hey James!
Read what I just wrote about E. above.
James,
I’m not in any way opposed to pursuing the goal of a unified theory, quite the opposite. I just happen to think that the current way string theory is being pursued and promoted is very much hurting the pursuit of that goal and someone should speak up about this. Preferably someone other than me, but that wasn’t happening. Sure, I’d rather be spending my time on more positive pursuits, but I just don’t see the problems with string theory being addressed. Instead I see a refusal to seriously address legitimate criticism, continued outrageous and misleading hyping of the theory, coupled with ad hominem attacks on anyone who dares to make such legitimate criticism. Given these circumstances I’m not too motivated to shut up about what is going on.
Peter,
To me, your complaints about the ‘attention that string theory receives by the media’ don’t seem to have anything to do with science. It really just seems like you and others are envious of that attention. Particle physicists have had the same experience for years from condensed matter physicists who feel that it receives too much money and attention. In fact, such jealousy is partially what lead to the cancellation of the SSC in 1993. There are reasons that people pursue string theory having to do with science that have nothing to do with how ‘glamorous’ the subject is in the popular culture.
E.
You are off the mark here. The issue isn’t high-energy physics
versus others in the science community. The issue is how to
allocate time and resources within high-energy physics.
Peter O.,
Very little money actually goes to theory at all when compared to other science disciplines. However, I don’t think attacking string theory is going to help this situation. Personally, I would like to see all areas of high-energy physics receive more money, not just string theory. I do think that within the string theory community itself, too much influence over what topics are important is in the hands of too few people, in particular the Princeton/Harvard/Stanford groups.
Also, for those who like to think of LQG as a viable alternative to string theory, the basic problem with it is perturbative renormalizability. As Lee Smolin pointed out, it may be possible to include gauge theory within the framework of LQG, but not in a unique way. One of the reasons for the initial excitement of string theory is that it was found that the anomalies canceled for only two choices of gauge group SO(32) and E8 x E8, in particular since E8 contains within it groups like SO(10) which hold great phenomenological interest.
E.
When you say “Very little money actually goes to theory at all
when compared to other science disciplines. However, I don’t
think attacking string theory is going to help this situation”,
it seems as though you mean we should shut up about our
concerns for the field, because others might get wind something
isn’t right. Such arguments are used to persuade people not
to rock the boat within every elite. Should goverment officials,
police, etc., not dispute what their communities do, because it
hurts their image? On the contrary, disputing how a community
often helps that community.
I think a serious debate (even peppered with nasty insults, as this
one seems to be), might increase positive public interest in
high-energy physics. In fact, I think it is already doing that.
Here’s a suggestion, why doesn’t Peter Woit denote all money he receives from his book and speaking engagements to people studying alternatives to string theory?
Peter O.: There’s nothing wrong with debating the merits of string theory. I think it holds up well in an honest debate. It’s the attacks that have nothing to do with science that are not helpful. They only serve to give the impression among the public that physicists don’t know what they’re doing and will in the end hurt all of high-energy physics. I do believe that the discovery of SUSY at LHC will provide some vindication, since this has been theorized on for thirty years ‘without showing any results’.
E.
Attacks are not helpful? Then what was all that about Peter W.’s publication record? Why this nonsense about his donating his
money to alternatives?
‘Here’s a suggestion, why doesn’t Peter Woit denote all money he receives from his book and speaking engagements to people studying alternatives to string theory?’ – E.
Smolin and Woit, the biggest critics who have written books, are both working on alternatives to string. The revenue from their writing and presentations (if these are actually commercial ventures??) isn’t a reliable or sustainable way to fund alternatives!
‘It’s the attacks that have nothing to do with science that are not helpful. They only serve to give the impression among the public that physicists don’t know what they’re doing and will in the end hurt all of high-energy physics.’ – E.
It’s not the attacks but string theory which isn’t even a speculative-yet-falsifiable theory, let alone science. The physicists working on non-falsifiable ideas, whether these are in mathematics or telepathy like Josephson’s http://arxiv.org/abs/physics/0312012 or supersymmetry, aren’t acting as physicists or scientists when they do this.
Seeing the amount of public hype these people sell in books, it’s fortunate there is some public-arena backlash, or the public would remain duped.
By the way, E. a lot of theoretical physicists who work on supersymmetry
are not as optimisitic as you are about its vindication at the LHC.
http://www.strings.ph.qmul.ac.uk/~dsb/dbwager.pdf
Anon: I respect Lee Smolin and the work he has done.
Peter O.: I would say that only a small minority are not optimistic about the discovery of SUSY at LHC. There are some very good reasons why we should see it. At any rate, we’ll soon find out. Who knows, maybe there will be some nice surprises. For the critics of string theory, I would say wait a couple of years until we have the results from LHC. If there is no SUSY, it would indeed be a big blow to string theory.
To add one note, as John Ellis has said, it is only the optimists who accomplish anything.
E., said “I would say that only a small minority are not optimistic
about the discovery of SUSY at LHC. ”
I think you are wrong about this. I don’t have any hard
statistics, but I talk with a lot of theorists and most privately think
superpartners won’t be seen. I don’t know if they would admit to
this in public.
By the way, since you bring up the subject of optimists, I am an optimist. My guess is that the LHC will eventually show us
something nobody anticipated. It’s not very optimistic to
think that all we’ll find is what people have predicted for
decades.
Peter O.,
Of course, there are the large extra dimensions people who believe TeV scale gravity will solve the hierarchy problem and the experimentalists at LHC will have black holes coming out of their ears, but don’t count on it.
As for what we’ll find at LHC, I think we can say that if the Higgs mechanism is correct, then you have to solve the hierarchy problem. There are two ways to solve the hierarchy problem, either there is TeV scale SUSY or the Planck scale is really TeV scale and gravity only seems weak because of large extra dimensions. If the Higgs mechanism isn’t correct, then we’ll be back at the drawing board.
My guess is that there may be some new states discovered besides the superpartners, perhaps the quarks and leptons of a heavy fourth generation or something completely exotic.
After reading some of the comments over at Clifford Johnson’s blog I just have to ask…if E. and James have actually bothered to read Woit and Smolin’s books? And bets on their answers?
Reader,
Yes, I’ve read them both.
Peter O.
Thanks for the link to the betting document, very interesting. I suspect even fewer would now be willing to bet on SUSY at the LHC.
E.,
The total income so far from my speaking engagements would support one postdoc for about one week. As for the book, it hasn’t quite yet earned back its advance, a sum which, after taxes would support a postdoc for about one semester. I suspect people’s ideas about the amount of filthy lucre I’m making on the backs of hard-working string theorists are unfortunately exaggerated.
I don’t think one or more postdoc- years to support people for whom there are no permanent jobs would change much. What’s required is a change in what is going on at the places that train the next generation of theorists. If Harvard or Princeton will offer me a discount and endow a permanent faculty position for non-string formal particle theory using the funds generated by my book and speaking engagements, I’m willing to make the donation.
E.: actually, if instead LHC finds that the hierarchy problem is a fake problem (e.g. by discovering no new physics beyond the Standard Model), this would be a great victory for anthropists, and a great Phyrric victory for string-landscape-anthropists.