Finally we get to some real substance in the program! (See earlier notes, and thoughts.) Jeff actually mentions all the effort going on string theory and experiments at Brookhaven, and asks that question I keep asking everyone… “why oh why is this never mentioned by the press in these discussions?” I’ve asked this of Peter Woit on his blog a lot too, for example, and have never got much of an answer. Peter and Lee want the world to believe -by reading their books- that the entire field of string theory is just people sitting around discussing the Anthropic Principle and lots of different universes, and blah blah blah… It serves the purpose of the books in question to completely distort the view of what is actually going on in the field. They claim that there is no experimental support (true) or hope for experimental support (how can they know that?) for string theory… but they ignore the fact -they intentionally don’t tell you, dear reader- about the interesting work going on by a huge percentage of the field to use string theory to study the structure of nuclear matter. It is still in its early stages, and may not work, but it is rather interesting. As Jeff put it, about the new form of matter that is constructed in these experiments, string theory is “the only approach that I know of” that currently seems to be able to explain the observed properties….
Lee, about the omission of this huge effort in string theory research from his book: “At least it is alluded to…”
That’s just lame.
He then proceeds to rather poorly attempt to claim that such contact with experiment (if this is indeed the case we don’t know for sure yet, I should say) is essentially beside the point. Nothing to do with whether string theory is a fundamental theory of Nature.
Sigh.
Dear reader, did you think I was exaggerating when I used the words “Storm in a Teacup”, “Self Interest”, and “Counter-Hype”?
-cvj
Peter,
What I am saying here is pretty much what Jacques and Clifford are saying. If they
When you say “You even seem to
disagree with this I’m sure they will speak up.
agree with me” all I can say is that seeming is in the eye of the beholder.
Jeff,
All I was referring to was that
“And certainly some people are getting a little bit too excited about this new possibility of making contact with experiment.”
seemed to me to be at least some acknowledgement that there was a bit of hype going on.
Incidentally, Peter, I’d like to thank you for your timely intervention. I was almost ready to start telling my friends that string theory has been very much more successful than I had thought.
Hi Prof. Harvey,
“If you don’t like or don’t think it is fascinating, fine, but then go find something else you do like and work on that.”
Some of us are doing exactly that. But we find it a bit difficult when competing with string theorists for jobs in formal particle theory groups. Young people working independently on non-string topics quickly discover that their single-author PRL publications count for nothing in competition against string theorists, especially when the latter in most of their papers are junior authors on papers with senior influential people.
Do you really think the preferential weighting for string theorists in formal particle theory job searches is a good and justifiable thing? (Surely you don’t deny that it exisits?) Now that string theorists are developing an interest for QCD physics, is there any prospect of string-dominated formal particle theory groups hiring (e.g. as postdocs) people who work directly on that topic? Or is it only the results that come via AdS/CFT that are of interest. Or perhaps it’s just that string theorists, thanks to their innate superiority, will always be able to do better than the practitioners of another field when they enter it. (In that case it’s kind of surprising that they haven’t been dominating the pages of PRL in the same way that they dominate on the job market, but I guess it’s just their natural modestly that restrains them from this.)
Regarding “hype”, the thing that irks some of us is the way string theorists seem to be presenting this application of AdS/CFT as more interesting and important than other work on RHIC physics (or QCD/Standard Model physics in general). An objective way to quantify its importance would be to count how many papers on it have been published in PRL, and divide this by the total number of PRL publications on theoretical RHIC physics – I suspect this would be a small fraction. More generally, you guys seem to think that AdS/CFT is the only important theoretical development in QCD in recent times. It isn’t. For example, developments regarding chirality in nonperturbative formulation of QCD are an order of magnitude more important for QCD physics than anything that has come from AdS/CFT so far. (E.g. it opens up the possibility of a first-principles investigation of spontaneous chiral symmetry breaking, and chiral phase transition at non-zero temperature. In contrast, AdS/CFT gives at most an approximate, effective theory description of chiral phase transition in finite temperature QCD. A first-principles treatment is preferable, right?) Btw, this chirality stuff has rich, interesting and subtle mathematics associated with it as well (anomalies, index theory,…) and allows to address rather interesting questions such as whether the Standard Model actually exists at the nonperturbative level. But only a career-suicidalist would work on such non-string stuff.
Amused –
Do you really think the preferential weighting for string theorists in formal particle theory job searches is a good and justifiable thing? (Surely you don’t deny that it exisits?)
I really sympathize with you.
It’s difficult for great, iconoclastic geniuses like to you to succeed while being crushed down by the great String Theory Conspiracy.
Your inability to find a job is unquestionably because you’ve seen through the great fraud that is string theory, and because the string theorists are jealous of your great ideas.
It’s not at all because you’re a nitwit crackpot or anything like that.
Dear amused,
Princeton recently hired a collider phenomenologist. Chicago has an offer out to
a senior phenomenologist and is planning a search for a junior person. Other
universitites with strong string theory groups are doing similar things. I’m sure some
good people working in other areas of particle theory have lost out to string theorists.
But the job market has not been a piece of cake for string theorists either, no matter
the impression that some people try to give that working in string theory amounts
to a guaranteed job. I’ve had several students in string theory who gave up on academics
because of the tough job market and several others who perserved and eventually got
good jobs but only after many postdocs, hanging on by a thread and much personal
sacrifice. Some of my best string theory students have also contributed in significant
ways to efforts in phenomenology.
You say that “string theorists seem to be presenting this application of AdS/CFT as more
interesting and important than other work on RHIC physics.” Wouldn’t you at least like
to qualify this to “some string theorists?” If you read my earlier post I think you will see
that I was quite clear in saying that the string theory calculations are only a small part of a
large and complicated story. I recently heard Starinets, one of the founders of this topic,
talk on the application of AdS/CFT to RHIC physics. He was also extremely careful to
point out that the data is very complicated to interpret and that the string theory calculations are only one approach among many. Among the string theorists I talk to I
don’t think one of them has been responsible for “hypeing” this subject. It is not hype
to say what is true, which is that there aren’t any other methods known for doing near equilibirium calculations in a strongly
coupled thermal gauge theory. No other calculation gives the small ratio of shear viscosity
to entropy. The bulk viscosity of gauge theory is such a complicated calculation that it
was first done using AdS/CFT techniques. It gives a novel approach to calculating the drag force on massive quarks moving through the QGP. This is why not just string
theorists but also experts in QCD and finite temperature gauge theory like my old colleague
Larry Yaffe are working on this.
Regarding chirality in non-perturbative formulations of QCD (by which I assume you mean
lattice QCD) I agree this is interesting and important work. Your “you guys seem to think”
tars all string theorists with a very broad brush. I don’t think as you said, and neither do
many other string theorists I know. Where do you get the idea that all string theorists think
alike?
As you may or may not know,
my work with Curt Callan played a small role in one of these formulations involving chiral
domain wall fermions. Here also string theory via AdS/CFT is starting to play an interesting
role (although a minor one so far). The recent work of Sakai and Sugimoto incorporates
chiral symmetry breaking into a string dual of QCD (and by the way, without supersymmetry) so for the first time one can study
the problem at strong ‘t Hooft coupling. In these models one can separate the scales of
confinement and chiral symmetry breaking (see hep-th/0604017). it should be possible
to check these ideas using lattice gauge theory, and conversely string theory
makes some interesting predictions that could be checked using lattice gauge theory.
I don’t think working in this area is at all career suicide.
It seems to me to be quite a fun and exciting time with string theory and other parts of particle physics having something interesting to say to each other and with possible experimental tests of the whole framework.
Regarding your proposal to measure things via PRL pages, I know that in some fields that counts for a lot, but in particle theory (and not just string theory) that went out as a useful measure of anything about 20 years ago.
Finally, a brief note to Peter Woit. Please stop misrepresenting what I say. If I had
wanted to say “there is a bit of hype going on” I would have said that. Saying ” some
people are getting a little bit too excited” is quite a different statement.
Jeff,
I was directly quoting your words, apologies for any misinterpretation of them, but I certainly wasn’t misrepresenting them.
Your response to “amused” gives plenty of evidence for one of the problems he is discussing, that string theory completely dominates formal particle theory. I’m sure it’s true that many institutions are trying to hire phenomenologists, but “amused” was not claiming that phenomenology is not getting enough attention.
“amused” also claims that it’s very difficult to get anyone interested in non-perturbative issues about QCD unless they can be approached via AdS/CFT. You respond by discussing AdS/CFT approaches and telling him that working on their relation to lattice gauge theory would not be career suicide, which I’m sure he’s well aware of. His question is about whether it’s possible to work on things that are not phenomenology and that have no relation to AdS/CFT.
And as for “Investment Spanker”, he provides yet a different sort of evidence for the problems with string theory and how it is being pursued.
Dear Prof Harvey,
Thanks very much for your response.
As Peter mentioned, the point I was making was that it seems pretty difficult for people working on non-string topics in formal particle theory (as opposed to phenomenology) to compete with string theorists for jobs, so your advice to “go find something else you do like and work on that” might not be a very good one for a young person who wants a career in this area (although I realize that you were directing it specifically at Peter). I’m aware that finding a job is no piece of cake for string theorists either, especially in recent years. But wouldn’t you agree that in general their chances are still considerably better than than for people working on non-string formal particle theory topics? How are the latter supposed to make themselves competitive on the job market? As a grad student and young postdoc (in obscure places) I naively thought that demonstrating independence and publishing on my own (including a few in PRL, our supposedly top journal?) might do the trick. Well, maybe I just didn’t do enough, or it wasn’t that interesting, or whatever. I’m certainly not claiming to be particularly deserving, or to have been “cheated” out of a job by the “string conspiracy” (contrary to what was suggested in “Investment Spanker”‘s moronic comment). I’m also well aware that there are other, much better people than me out there who are having a tough time. But my case and others do provide some kind of lower bounds on what it takes for a non-string person to be competitive for jobs in formal particle theory, and leaves me curious about what it would really take to be successful. Can you enlighten me on this – what would it take for your group to hire, say as a postdoc, someone working on a non-string particle theory topic?
“You say that “string theorists seem to be presenting this application of AdS/CFT as more interesting and important than other work on RHIC physics.†Wouldn’t you at least like to qualify this to “some string theorists?â€
Ok, fair enough. The general impression I’ve gotten from string theorists’ presentations (those I’ve seen or read, which admittedly isn’t many, and which doesn’t include any by you) is that this is to be seen as a great triumph for string theory and vindication of it as a research program. Well, sure it’s a triumph, sure it’s interesting, and I can certainly understand people being excited about it. But these things are relative. As far as the impact on QCD physics goes, how important is this compared, e.g., to solving the chirality problem for fermions on the lattice? Or compared to other theoretical advances regarding RHIC physics or QCD in general…. What seems to be missing, at least from what I’ve seen, is a sense of proportion, a discussion or at least acknowledgement of how this development is one of many interesting ones, that it’s full significance remains to be seen, and similar stuff in that vein. If the presentations had all been as reasonable and balanced as your description above, I don’t think these hype complaints would have arisen. But unfortunately they aren’t.
“Your “you guys seem to think†tars all string theorists with a very broad brush. I don’t think as you said, and neither do many other string theorists I know. Where do you get the idea that all string theorists think
alike?”
If you can point out any string theorist or string-dominated particle theory group that would be remotely interested in hiring or supporting anyone working directly on QCD theory (i.e. not via AdS/CFT) I’ll humbly take it all back.
“As you may or may not know, my work with Curt Callan played a small role in one of these formulations involving chiral domain wall fermions”
I’m familiar enough with your work with Callan to know that your description of it as having played a “small role” is far too modest.
“…It should be possible to check these ideas using lattice gauge theory, and conversely string theory makes some interesting predictions that could be checked using lattice gauge theory….It seems to me to be quite a fun and exciting time with string theory and other parts of particle physics having something interesting to say to each other and with possible experimental tests of the whole framework.”
Sure, I agree completely. But is this going to be an arrangement where string theorists provide the theoretical brains and lattice folks are just supposed to supply the numerical brawn? The developments regarding chirality on the lattice were of a formal theory nature, and there are plenty more interesting and important things that remain to be done on that. (Hamiltonian formulation, understanding CP symmetry, anomalies and their cancellation in chiral gauge theories on the lattice,…). But working on this formal stuff pretty much is career suicide. Who is going to hire such a person? Traditional lattice groups aren’t interested (which is kind of understandable since they are heavily invested in numerical QCD). The natural home for such person would be in a formal particle theory group, but for “most” of them you have to be doing string/brane stuff.
“Regarding your proposal to measure things via PRL pages, [...] in particle theory (and not just string theory) that went out as a useful measure of anything about 20 years ago.”
Really? That’s at odds with my impression. The physicists I know of seem to regard publishing there as a bit out of the ordinary, and want to publish there when they do some thing they consider a bit out of the ordinary. That includes senior physicists who definitely consider themselves particle theorists. It also seems to be the case for various string and brane folks (for starters, Randall&Sundrum…). But if PRL publications isn’t a useful measure (and I’m not insisting that it is), then what is a useful measure these days? Is there one? This brings me back to a question from the beginning, about what it takes for non-string people to make themselves competitive for jobs in formal particle theory. Without some (semi-)objective, impartial measure it’s going to be kind of difficult, right?
Investment Spanker:
“I really sympathize with you.”
Gee, thanks.
“It’s difficult for great, iconoclastic geniuses like to you to succeed while being crushed down by the great String Theory Conspiracy.”
Yeah, its tough. But we’ll get our own back when the Revolution comes.
“Your inability to find a job is unquestionably because you’ve seen through the great fraud that is string theory, and because the string theorists are jealous of your great ideas.”
Ah yes, that must be it. How perceptive of you.
“It’s not at all because you’re a nitwit crackpot or anything like that.”
Certainly not. Glad we got that straight. Now let me tell you about my brilliant discovery of a Theory of Everything based on little pulsating squiggly thingies…
(Btw, despite my inability to find one, I do somehow appear to have a job in physics at the present time… at any rate, some or other university seems to be putting money into my bank account each month, and doesn’t seem to mind my occasional use of one of their offices for scribbling and blog-surfing…)
Dear amused,
Thanks for your thoughtful and tactful response. I agree with you that we are lacking in good
(semi-) objective measures of what work should be supported, in main part because
of the absence of data. I think that applies equally to string theory, other parts of
formal particle theory, and much of what is now called “phenomenology.” And
entrenched groups whether in string theory, lattice gauge theory, brane-worlds,
perturbative QCD or what have you have a tendency to hire people who work in the same area. I think not so much because they are trying to keep the upper hand, but because they want people they can talk to and collaborate with. I really don’t have any good generic job advice (or maybe am just not in the mood), but if you want to send me email I’d be happy to discuss it in private. if you don’t want to give up your anonymity just creat an email
account on gmail or yahoo and send me an email with “amused” in the subject line.
I would like to point out two recent papers related to the “strongly coupled” QGP discussion and the viscosity bound which I found very interesting and readable:
The Letter "s" (and the sQGP) by Jamie Nagle (nucl-th/0608070) gives a nice discussion of all the different notions of strong interactions and strong coupling involved in the debate about the hot and dense nuclear matter created at RHIC.
On the Strongly-Interacting Low-Viscosity Matter Created in Relativistic Nuclear Collisions by Laszlo P. Csernai, Joe Kapusta, and Larry McLerran (nucl-th/0604032) presents a new and fancy way to plot the phase diagram of fluids in the vicinity of the critical point: They plot the ration of shear viscosity to entropy density as a function of temperature for different pressures. These curves seem to look quite similar for all kinds of fluids, with a kink when hitting the critical point. Moreoever, this kink corresponds to the absolute minimum of eta/s for the fluid under discussion, and it is allways higher than the AdS/CFT bound, which seem to be quite universal indeed! This paper was published as a PRL last week, and it seems to have been directly motivated by the Kovtun-Son-Starinets PRL. However, it does not (if I did not miss that point somehow) discuss whether AdS/CFT says anything more specific about RHIC matter or not.
Stefan:- Thanks a lot for those references … they were very interesting indeed. It is such a fascinating area!
Cheers,
-cvj
if everyone is so high-minded and interested in science and all, why are you all so damned mean to each other? i think you should strive to make your posts in the form of:
“Q: what is the connection between QCD and 10Mplank” (or whatever)
rather than
“Q: what is the connection between QCD and 10Mplank and by the way, stop intentionally misrepresenting my spin on your interpretation of my post to the 137th comment on your response to my explanation of your hostility about my feelings about your sneering about my dismissiveness”
really it’s like a dysfunctional family gathering or something rather than point-counterpoint!
in this respect probably trading scientific questions by physical mail, with postage stamps and having to pay for each page of paper, might’ve done science better than this insta-flame-war-promotting-blogging bs.
I’ve just plowed through about a hundred blogs, all-too-human stuff. I read the New Yorker review, entitled “Unstrung,” which seemed to me fair enough. I worked for Science Magazine for years and have read hundreds of scientific papers. I am now 85 years old. As a professional “discipline,” science is an epistemology that answers the question, “What do you know and how do you know it?” by the convention of repeating “experiments.” These are based upon what the experimenters see as a result of manipulating material objects in unnatural ways (not too different from tying a can on the cat’s tail to see what happens, or dissecting a frog to see what’s inside). Science depends upon consensus among the experimenters, just as religious communities depend upon a consensus of beliefs. Answering the question “Do you see what I see?” binds communities together intellectually, making (in my opinion) science and religion indistinguishable. In my view, there are just as many “scientific” worlds as there are mothers, and as many godheads. Your god is not my god, your mother is not my mother, your science is not my science, and what you call “the” world is not my world. Perhaps each of us is a unique ripple of space, time, energy, and matter. There are as many dimensions (directions) of STEM as there are radiants of light (an infinity), and just as obviously an infinity of dimensions (sizes) of STEM, just as there is an infinity of possible organisms. Whether all ripples of whatsoever size can be shown to function according to a single dynamic that also governs our own species of STEM is an open question. Lastly, I suggest that science give up the notion of nature and creation as entities that are MADE (a theological precept). STEM happens, randomly, and unpredictably, despite our incurable beliefs, e.g., that the sun rises and sets. and that apples fall as expected. Best wishes to everyone!
Dear Prof. Harvey,
Thanks, I’m glad you agree about the problem with (lack of) good objective measures. One thing that could maybe be done is to re-establish the role of journals in providing “quality stamps”. In the maths community, someone working on a less fashionable topic can still get attention and career opportunities if they can “prove” the quality of their work by getting it published in top maths journals. I don’t see any principle reason why a system like that couldn’t work in physics (including theoretical particle physics), and I think it would go a long way towards alleviating the “sociological” complaints against string theory: No reasonable person is going to complain about jobs going to the “best people”, and if these happen to be string theorists then so be it, as long as they really are seen to be the best by some reasonably objective measure(s).
Thanks very much for your kind offer for me to contact you privately. But I’ll respectfully decline this, since my purpose here has been to raise general issues and not to seek personal help or advice.