I have a long-percolating post that I hope to finish soon (when everything else is finished!) on “Why String Theory Must Be Right.” Not because it actually must be right, of course; it’s an hypothesis that will ultimately have to be tested against data. But there are very good reasons to think that something like string theory is going to be part of the ultimate understanding of quantum gravity, and it would be nice if more people knew what those reasons were.
Of course, it would be even nicer if those reasons were explained (to interested non-physicists as well as other physicists who are not specialists) by string theorists themselves. Unfortunately, they’re not. Most string theorists (not all, obviously; there are laudable exceptions) seem to not deem it worth their time to make much of an effort to explain why this theory with no empirical support whatsoever is nevertheless so promising. (Which it is.) Meanwhile, people who think that string theory has hit a dead end and should admit defeat — who are a tiny minority of those who are well-informed about the subject — are getting their message out with devastating effectiveness.
The latest manifestation of this trend is this video dialogue on Bloggingheads.tv, featuring science writers John Horgan and George Johnson. (Via Not Even Wrong.) Horgan is explicitly anti-string theory, while Johnson is more willing to admit that it might be worthwhile, and he’s not really qualified to pass judgment. But you’ll hear things like “string theory is just not a serious enterprise,” and see it compared to pseudoscience, postmodernism, and theology. (Pick the boogeyman of your choice!)
One of their pieces of evidence for the decline of string theory is a recent public debate between Brian Greene and Lawrence Krauss about the status of string theory. They seemed to take the very existence of such a debate as evidence that string theory isn’t really science any more — as if serious scientific subjects were never to be debated in public. Peter Woit agrees that “things are not looking good for a physical theory when there start being public debates on the subject”; indeed, I’m just about ready to give up on evolution for just that reason.
In their rush to find evidence for the conclusion they want to reach, everyone seems to be ignoring the fact that having public debates is actually a good thing, whatever the state of health of a particular field might be. The existence of a public debate isn’t evidence that a field is in trouble; it’s evidence that there is an unresolved scientific question about which many people are interested, which is wonderful. Science writers, of all people, should understand this. It’s not our job as researchers to hide away from the rest of the world until we’re absolutely sure that we’ve figured it all out, and only then share what we’ve learned; science is a process, and it needn’t be an especially esoteric one. There’s nothing illegitimate or unsavory about allowing the hoi-polloi the occasional glimpse at how the sausage is made.
What is illegitimate is when the view thereby provided is highly distorted. I’ve long supported the rights of stringy skeptics to get their arguments out to a wide audience, even if I don’t agree with them myself. The correct response on the part of those of us who appreciate the promise of string theory is to come back with our (vastly superior, of course) counter-arguments. The free market of ideas, I’m sure you’ve heard it all before.
Come on, string theorists! Make some effort to explain to everyone why this set of lofty speculations is as promising as you know it to be. It won’t hurt too much, really.
Update: Just to clarify the background of the above-mentioned debate. The original idea did not come from Brian or Lawrence; it was organized (they’ve told me) by the Smithsonian to generate interest and excitement for the adventure of particle physics, especially in the DC area, and they agreed to participate to help achieve this laudable purpose. The fact, as mentioned on Bloggingheads, that the participants were joking and enjoying themselves is evidence that they are friends who respect each other and understand that they are ultimately on the same side; not evidence that string theory itself is a joke.
It would be a shame if leading scientists were discouraged from participating in such events out of fear that discussing controversies in public gave people the wrong impression about the health of their field.
Following up on Former string theorist’s insightful comment above:
There is nothing new or intrinsically bad about an “elite” research subcommunity detaching from the main community and exalting in the brilliance of its members. That seems to happen quite a bit in pure mathematics, for example. Elitism in science is not a bad thing, it seems to have been beneficial for progress in the past. Also, if the elite community attracts and admits the best and the brightest then it is natural that these people should dominate the job market. But such a community really needs to earn its status on merit. The “sociological objection” that some of us have about the string theory community is that its status is way out of proportion with what has been earned on merit. That’s not to say that ST isn’t an interesting and worthwhile research topic (which I certainly consider it to be from a mathematical physics perspective, regardless of the lack of connection to nature so far). But there is no way it can reasonably claim to have earned the hegemonic position that it now occupies in formal particle theory.
If ST had earned its position it would be demonstrated in tangible ways. For example, ST papers would be dominating the pages of PRL. Yes, I know the usual string theorists’ retort to that argument: journals are irrelevant, no one cares or attaches value to being published in a particular journal anymore, etc etc. Funny then how string theorists who profess not to care about journals seem so keen to get published in that particular journal when they have done something they consider a big deal. We have an example right here in this thread: take a look at the paper hep-th/0703280 by Eric Mayes et al discussed above — it’s clear from the format which journal they hope to publish in. That particular journal involves much extra hassle; the draconian 4 page limit is just the beginning of it. Why go to all the trouble when other journals, e.g. JHEP, are much less hassle? The schizophrenic attitude of string theorists towards journals, and PRL in particular, is really quite funny.
If string theory is losing the public debate it’s pretty naive to think that that could be reversed simply by better explaining the motivations for ST. Journalists who write about this will surely also be taking into account the vibe they pick up from insiders within the mainstream physics community, and Sean has already noted in an earlier post the “surprising” level of distain and resentment towards ST there. Even people who are basically sympathetic to ST and fully understand its motivations are not happy with the current situation (remember JoAnne’s post?). String theorists need to stop responding by strawman arguments – pretending that the issue is whether or not string theory is a waste of time and then arguing that it isn’t. The issue is all about merit – having to earn what you get rather then claiming exemption from usual competition due to special genius status. The most important message from the growing antagonism towards ST is that string theorists need to start proving themselves meritous of their privileged status in tangible ways. Non-string physicists seem to be no longer swallowing “Ed Witten is our leader and he is smarter than everyone else” as a justification for continued string dominance. Writing out a list of motivations and nice features of ST won’t cut it either – people working on other topics can do that as well.
As mentioned, elite research sub-communities are nothing new and sometimes form, e.g., in pure maths. But those elites are never recipients of the kind of antagonism currently directed at string theory. If anyone were to complain, the members of the elite could simply respond as follows: “Look, we play by the same rules as everyone else. There are tangible, universally accepted measures of merit in our community, and by these we have proven ourselves more meritous than the other folks. You might not be able to appreciate the greatness of the work we are doing (after all, it isn’t your topic) but you certainly know and respect the standards of the Annals of Math. and Inventiones Mathematicae, and look how many papers we have published there! A whole lot more than you and your cohorts. So shut up and sod off.” What can string theorists offer as tangible justification for ST dominance? Imagine a hypothetical job interview for hot young string theorist X: Non-string committee member A askes: “Dude, if you are as brilliant as you and other stringers think you are, how come you don’t have some papers in PRL?” To which X responds: “Oh, I could have published plenty there if I wanted to, but I just couldn’t be bothered. As long as Joe Polchinski thinks my work is great, why should I care what the editors and referees of PRL think?” To which A replies: “But then how am I supposed to compare and evaluate you against the non-string candidates?” X replies: “Come on man, if they were any good they would have been doing string theory!”.
Yes, I know, publishing in PRL doesn’t prove that the paper is great, etc, etc. But on the other hand, it’s still the least trivial physics journal to get publish in, and if someone has done something great they should be able to get it published there. So, unless they have a better idea for how to prove themselves meritous of their special genius status and the perks that go with it, string theorists might want to consider PRL publications as a way to do it. Lets see if they can dominate the pages of PRL as much as they dominate the job market. If dimwitted outsiders like yours truly can manage to publish there it should be a piece of cake for brilliant young string theorists. In any case, I don’t think string theorists have any chance of winning the public debate until they manage to convince the bulk of non-string physicists that their exalted position is based on tangible merit rather than various sociological peculiarities.
(Damn, I’ve got to get out of this marathon comment habit.)
George Musser:the grant process devours too much productive time and discourages out-of-the-box thinking of the sort Peter thinks is neglected.
String theory is thinking outside the box, so I do not know how one could claim that we should be doing this, and then criticize such thinking? 🙂 I’d be interested to know how your staff can come to any such conclusion as you have explained above.
As per #125, I do not know why more string theorists have not step forward?
Plato writes:
Sorry, I don’t understand what you’re saying. When did I criticize that you are doing out-of-the-box thinking? What conclusions have my fellow-staffers or I reached? Maybe you are reading more into my little message than I said!
It does seem, though, that insides and outsides of boxes are frame-dependent.
George
The issue is all about merit – having to earn what you get rather then claiming exemption from usual competition due to special genius status.
I’m very confused here. Who’s claiming to be exempt from usual competition?
The most important message from the growing antagonism towards ST is that string theorists need to start proving themselves meritous of their privileged status in tangible ways. Non-string physicists seem to be no longer swallowing “Ed Witten is our leader and he is smarter than everyone else” as a justification for continued string dominance.
I certainly hope no one ever states that as justification. It’s inane. I can certainly say that when I was looking at graduate schools and talking to people about various things to study, statements such as the above or the experiences of “former string theorist” above never ocurred. In fact, I remember various people patiently responding to my questions about background independence, the perturbation expansion, etc. Perhaps I was just lucky.
I can’t say I understand this PRL fetish though. Maybe it’s just cultural. I certainly would not agree with the statement that journals are irrelevant; publication provides a valuable check on preprint culture (which reminds me that I need to replace one of my preprints with the published version.) String theorists publish in PRD, NPB, CQG, CMP, ATMP, JHEP and probably plenty of others. I bet there are even been publications in PRL. What’s the big deal?
George,
Thanks for your comment, which does bring things back to what I see as the most important point, which is how to get particle theory out of its current doldrums. It seems to me that we’re stuck for several reasons, with some of them ones we can’t do anything about:
1. Our experimental techniques are reaching fundamental technological limits: it’s harder and harder to get to higher energy.
2. The standard model is too good: the absence of experimental anomalies that could tell us which direction to look for progress is a huge handicap.
That said, there are aspects of the problem that in principle can be addressed, especially:
3. A huge amount of time and effort has gone into the pursuit of a very speculative idea (string-based unification) which does not work. People who have put in this time and effort are loathe to admit failure, and to make the effort to retool and try other speculative ideas.
The main question I see is that of figuring out how to change the incentive structure in this field to get people to try a wider variety of ideas. As long as the incentives are set so as to encourage continuing down a failed path, that’s what we’re going to get. I think it’s highly unfortunate that I, Lee and others have had to spend our time dealing with ad hominem attacks from people who want to deny that this program has failed, and claim that it continues to be the most promising way for people to spend their time. I don’t think Sean has it right: what’s needed is not more string theorists publicly making the case for string theory. Lots of people don’t want to do this because they know how weak it is. What is needed is instead some serious coming to grips with the problems Lee and I have discussed, acknowledgment that they are real and serious proposals about what to do about them.
Dear Amused,
String theorists do publish in PRL occasionally. For most string theory papers this is not possible: the length restriction is the main reason. For technical reasons, modern string theory papers require long computations of certain kinds and presenting them in a four page format is very difficult. Moreover, since in general it’s hard to compare to data, one can not very easily just write a paper about such a hypothetical comparison for a model. You also have to remember that papers published in PRL should be interesting to a broad audience.
Regarding your other comments, string theorists do compete for grant money with other physicists that do particle physics phenomenology and sometimes gravitational physics as well. There is no preferential treatment (no string theory section of NSF, lets say). A lot of the debate is misleading exactly because people who do research in string theory are characterized as “hogging the money”, as if there would be no competition.
The main reason I usually stay out of the “string waars” debate is because in my experience people do not want to listen to reason: they already know what their opinion is and are not willing to change it. Instead the discussion degenerates very quickly.
If most people in, say, particle theory are string theorists (not sure if that’s true, just a hypothetical) would it not be the case that most people sitting on the funding panels are string theorists? If that were the case, there wouldn’t have to be a ‘string theory section of NSF’ for string theory to maintain a financial edge.
Marty (#125), please re-read precisely what I wrote in #94, and try not to substitute with what you think would make a better story. For example, not sure where “understand it on a technical level” came from, I don’t see it in anything I wrote here or elsewhere. I can be quite confident in that since it is contrary to my opinions.
And to reiterate, there are a lot of discussions here and elsewhere on various topics in physics, they are pleasant and fun for everyone involved, professional and lay-people. I think that a precondition to have (one of these days) such a physics discussion on the subject of string theory, on any level of technical knowledge, is to lay the debate on its merits to rest. Everyone already made up their minds long time ago, it’s not going anywhere.
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Moshe,
I wasn’t intentionally trying to misrepresent your point of view. I agree that after reading your comment #133 and rereading #94 I very may well have done so. What gave me the impression was where you said,
Apparently I read more into “the physics” than what you meant. I apologize, but trust that you can at least imagine how I might have interpreted your comment that way.
Nonetheless, I think you and others who agree with you are making a strategic mistake to act on the belief that
The universe of people who can form opinions is not limited to those you and others have publicly sparred with, so I think it is a bit of a generalization to say that everyone has already made up their mind. I also think it is unfair to assume that everyone who has already formed an opinion is unwilling to change that opinion.
This blog is widely read by people of different kinds of expertise. Certainly some journalists, perhaps more than we may think, use it as a resource to gain insight into the status of a major research program in theoretical physics, and then use that to inform or influence others who will never read this blog. It is hard to know how many other people of influence in science funding do the same thing. If those who find the string program most compelling are unwilling to explain why they think it is so worthwhile when offered a good forum for it, then by default the dominant impression is less favorable. I don’t see how that can work to the advantage of string theorists, especially because the prospects that string theory will have practical use are close to none; over the long term, the case for continued levels of significant funding will ultimately need to be made on more aesthetic grounds.
Marty, thanks a lot for the clarification. Let me try to respond in kind.
So, there is no doubt that string theory, and any other research program, needs to be presented to the public, who is after all the main source of funding for the program. I think string theory has, over the years, been very successful in presenting itself to the public on different levels. Of course having an exceptional communicator such as Brian Greene does not hurt. So I really see no general problem at the level of activity on the “outreach” front. I certainly have no objections for people to keep presenting the wonderful things we keep on discovering.
What I think has exhausted itself is the attempt to justify ourselves in this forum, and in fact right now this stands on the way of trying to have any exposition of the physics that does not immediately turn into a free for all “debate”. There is the set of people whom I referred to earlier, the ones that think that things like “string theorists are arrogant” is the ultimate argument on the subject , and I don’t think anything we can say about the physics of string theory will change their minds, so be it. There are also people like Lee and Peter, who for the most part present technical points. Those points have been thoroughly discussed many times, most recently here by no other than Joe Polchinski, so at this point we can just agree to disagree. If there are additional such points I’d be happy to discuss them in detail, but that has not happened in a little while.
Also, one of your points is very well taken. The commentary on blogs somehow tends to exaggerate the loudest voices, and after hearing the same voices completely unchanged for a couple of years, it is heartening to discover that some people are actually listening.
Peter,
At present we do not have any consistent theory that contains the standard model and gravity. I’d like to have one. Do you think this is a reasonable goal? In my opinion, string theory is the closest to meeting that goal. Do you have another recommendation?
Presumably, whether it is a reasonable goal has to be informed in part by how achieveable we believe it to be, rather than just picking the most promising. It seems that not everyone believes that it’s possible in the now, at least not in the scientific way, to wit, by making falsifiable predictions.
I’d like an everlasting jetpack that weighs 3 pounds. Is that a reasonable goal?
Jim writes: “The 10,000 years part gets me. We didn’t pull the [age of] the Earth out of a hat. It’s based upon radioactive isotope dating.”
Agreed. There are a couple of arguments that strict Creationists use. One is that all of this fossil evidence (and cosmological evidence) was “planted” by God. (A test of faith.) Other Creationists argue that C-14 (etc) dating is flawed. As I recall, most of the Creationist experts do not have PhDs in physics.
I see a vast range of belief between strict neo-darwinism/cosmology and the 5000 year Earth theory. Most public debates are between radicals on both sides (“minds are computers made of meat” vs timelines based on Biblical family trees).
Evolution is a touchy issue a) because people don’t like being compared to monkeys and b) because it conflicts with some literal readings of religious texts. But the Bible has tons of symbolism, and much Buddhist text is similar, not *all* of it is meant to be taken literally. And the Bible never ever says the first few “days” were Earth days.
Moshe:
This is the second comment you do here that doesn’t ring 100 % true to me. About the first, about no one changing his mind, wasn’t too clear if it was referring to experts or not. But in this comment you refer to non experts, so I feel that I can speak up.
When I out of curiosity tried to orient myself about the front edges of theoretical physics, it was exactly the information about motivations behind string theory that was hardest to come by. It wasn’t obvious what motivated the idea to look at objects such as strings – which seems natural to ask when there is only consistency and unverified results. (Branes was much easier to grasp in comparison, IMHO they don’t look so ad hoc at first glance.)
Compare with LQG, which presented both motivations and results up front. It takes a while to see penetrate the bluster to see that one can’t find many attempts to check for obvious things, but rather statements that it is possible or done.
So for once Wikipedia seems to be on the level of many blog commenters and papers: “LQG is a quantization of a classical Lagrangian field theory which is equivalent to the usual Einstein-Cartan theory in that it leads to the same equations of motion describing general relativity with torsion. As such, it can be argued that LQG respects local Lorentz invariance.” ( http://en.wikipedia.org/wiki/Quantum_loop_gravity )
Yeah, right, perhaps the quantization doesn’t change the thing we presumably want to check, so at least we can argue. (Funny that QFT’s seems to have a need to do this, though. At least what I can grasp of the descriptions with my feeble understanding here.)
Now, perhaps I can interest the author of above in a certain bridge I happen to own…
In conclusion, why not present the motivations to help laymen and other interested access the ideas and their results? For example, Distler’s post is quite good. One must but find it.
Ahh, the polyphyletic heresy! In the cladists view we *are* monkeys. 🙂
I think I can summarize the debate. Theory is *way* ahead of experiment. The LHC will turn up some new stuff, and everyone will scramble to explain it. But I think the law of diminishing returns will hit colliders soon.
And even if string theory fizzles out, there will be some other crazy theory in its place. Unless government comes up with a few trillion for a collider, there is going to be a lot of mathematical masturbation / speculation in the next few years.
The solution is obvious … convince the DOD that this research can lead to new weapons.
Aaron,
My “exemption from usual competition” remark was referring to the fact that over the last decade or so many young string theorists have been hired to faculty positions, often with relatively short publication records, while the same was not happening to anywhere near the same extent for young people working on other topics and whose publication records were just as good if not better in some cases. (Not me, but i know of others.) Why was this happening? Presumably because senior string theorists promoted these people as being extremely good, and string theory was considered hot at the time. Regardless of how brilliant these young string theorists might or might not have been, I hardly think the hirings can be described as based on tangible merit which was clear to all.
Regarding the “Ed Witten” remark, it was of course an oversimplification (for the sake of brevity). But wouldn’t it be fair to say that a large part of the reasons why physics departments were willing to stock up on string theorists to the extent that they did were because Witten and other leading lights in particle theory considered it the way to go and were so excited about it? I’m not trying to say that they all followed Witten like mindless zombies, but when the leading lights of fundamental physics get so excited about something and devote themselves to working on it that’s obviously going to have a big impact on what other people think, especially those working in other fields who dont’ have the background or inclination to look into the string developments themselves.
As for PRL, anyone who submits a paper there must have a fetish! For the simple reason that submitting there is more hassle than submittting to a regular journal (there’s the 4 page limit, and then you also have to be careful to write the paper in a certain way to pretend that it’s addressed to the “broad audience”, etc). No reason at all to put yourself through that unless you feel there is something special about publishing in that journal. (If someone just wants to publish in a broad audience journal they can avoid the hassle and use Ann.Phys.) Witten, Vafa, Strominger and many of the other leading figures of ST have published in PRL in recent years so I guess they must all have the fetish. Seriously though, have things really reached the stage where journal publications are nothing more than a check on the preprint culture? When I was a grad student in the mid ’90’s there definitely seemed to be a journal hierarchy in theoretical hep, with PRL at the top (or CMP for the mathematically inclined), followed by NPB, and then the more “lowly” ones. I remember a string theory postdoc at my institution being congradulated and praised by the faculty not so much for the work he had done but for the fact that he got it published in PRL! Having a journal hierarchy with a broad spectrum journal like PRL at the top is very valuable imo since it provides an objective measure system for determining relative meritousness of people working on different topics. The mathematicians have this and it has stood them in very good stead. Of course, it can only work if people take it seriously and unfortunately that doesn’t seem to be the case anymore in theoretical hep. But I think it would be very much in string theorists’ long-term interests to re-establish it, since then they will be able to use it to demonstrate that their own dominant position in formal particle theory is merit-based.
David B,
I can’t imagine string theory being that different from other topics in hep theory regarding long calculations. The usual thing in my experience when one wants to publish in PRL (or any letter journal) is to outline the key steps of the calculation and then give the full details in a subsequent longer paper. As for your remark about PRL papers having to be interesting to a broad audience, my impression is that if you can make a good enough case for the importance of the result(s) then it will get through. I’ve managed to slip some pretty technical stuff into PRL in the past, and have seen others do it as well.
As for competition for grants, I can’t say anything about that since I’ve no experience or knowledge of it. The things I wrote were mainly concerning the merit issue in for getting jobs. It seems to me that there is indirect preferential treament happening here, not due to any “string conspiracy” but simply because of the need to have the strong support of influential senior people if you want to get anywhere. This means that you had better be working on a topic that plenty of such people have committed themselves to, which pretty much excludes anything other than strings/branes in formal particle theory. This wouldn’t be the case if we had a journal system as in the maths community since then young people could prove themselves meritous simply by publishing in the top journals.
Actually George the right person picked up on it and thanked you, thinking it was a attack on them. This was not meant to be a sarcastic but a true observation before the rise of science wars.
I think someone said conflict in physics is good from the perspective that it could bring forward further information? If someone acts as a resounding board and continually repeats the same mantra, they become it.
So society is manifesting the mantra and reporters too? How could a research media group conclude such a thing, without having someone on that group effectively trained? I have certainly been held in “this light” and I should sent this forward?
Now, to think the technical aspect were not being dealt with and signalling out Jacques for a reference to his site is somehow going to make me feel I am in a better position speaking about string theory is ludicrous.
If people had followed these continued debates they would have understood that the technical issues were indeed being addressed “countless times” in other places. There was progress in those cases.
Outreach is a good thing. People have been listening. Blogs like cosmic variance have indeed played a good part in bringing people from their fields for contributions. I am glad that some string theorists have come forward.:)
Our views on cosmology have changed by modelled approaches? Provided for a earlier perspective on the cosmos.
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Gavin,
I don’t actually agree that string theory is the “closest” to meeting the goal of having a consistent combination of the SM and quantum gravity. It hasn’t succeeded despite decades of effort, and so the LQG people can reasonably make the case that they are just as likely to be “close”. But I don’t think the LQG/string theory question is the important one.
Personally, I’m actually not so interested in a “consistent theory of the SM and gravity” if it is highly artificial, mathematically ugly, doesn’t explain much of anything about the world, and is completely untestable. That’s where the string theory “unification” program is going. If you want the SM, you have to stabilize moduli, make all sorts of assumptions that things will work out, then end up with a complicated set of possible points in the landscape.
What has happened is that people have pursued the string theory unification program far enough to see that hugely complicated, ugly and artificial constructions are needed in order to get something that looks like the real world, so much so that the framework is unpredictive and untestable. Pursuing this further, in hopes of tying down the technical difficulties of completely realizing this picture, seems to me like a waste of time. It’s clear by now this is just a wrong idea about how to go about getting unification.
Here are some things _I_ like in string theory, and why I think it’s a step in the right direction.
– It proposes a way to quantize gravity consistent with the RG ideas (see Distler’s post linked by wolfgang #13) and *at the same time* it provides ways to produce extensions of the standard model. Yes, it does so in many ways; but at least discretely many, which is better than the “continuously many” in QFT.
– The assumptions regarding its dynamics can be put through “thought experiments” in many cases. Two examples: 1) mirror symmetry gives a spectacular check of the string instanton series. I think this would deserve to be more widely advertised outside the field. 2) AdS/CFT. To be sure: these are only “mathematical physics” tests, and of course they don’t tell us that the theory is a correct description of nature.
– One can sometimes reproduce topology change by an effective qft (I’m referring to the way CY transitions are reproduced by massless branes), in a way which is in my opinion quite elegant.
(This is a personal, idiosyncratic list — I left out dualities, the potential for inflation, black holes, which have all been discussed already here.)
I don’t understand all the complaints about its not being *currently* testable. We all have a problem: how to detect quantum gravity effects? The fact that there is today no answer to this is not ST’s fault. Replace it with another theory of QG, and the problem remains.
My “exemption from usual competition” remark was referring to the fact that over the last decade or so many young string theorists have been hired to faculty positions, often with relatively short publication records, while the same was not happening to anywhere near the same extent for young people working on other topics and whose publication records were just as good if not better in some cases.
Excuse me? Why in these discussions do I feel like I live in a completely different universe than many of the other participants? When I tell people in other areas of physics the number of postdocs that the average string theorist goes through before getting a job, they’re often shocked. I can think of a few exceptional cases, but the vast majority of string jobs, as best I can tell, go to people on at least their second postdoc.
Seriously though, have things really reached the stage where journal publications are nothing more than a check on the preprint culture?
What’s wrong with that?
I guess I can’t see what the big deal is with PRL. In fact, I seem to remember seeing some pretty ordinary papers in there, but I could be misremembering. Regardless, I find your journal argument to be rather circular. Who do you think would be refereeing the relevant papers?
Alright, here are things that brighten the day, such as tomorrow, when I teach beginning string theory course: you just start with a purely intellectual exercise, quantizing a relativistic string. You know you’d immediately run into trouble because combining Lorentz invariance and quantum mechanics is very tricky in field theory, requiring delicate structures such as gauge invariance for vector fields. So you expect complete disaster, all kinds of nonsense, but you are stubborn…
Instead, to everyone’s surprise (try to quantize relativistic membranes if you don’t believe it), everything falls into place effortlessly- the theory cannot be tuned and modified, so it lives dangerously, every time you check something new you may prove it inconsistent, and will simply have to abandon it. Somehow, again and again it is just right. Gravity, Einstein equation, matter fields with rough similarity to the real world (gauge fields, chiral fermions), they all just come out. It is impossible I think to go through the first few steps in string theory without the feeling of awe, there is something there that is very correct and unique.
Of course, this is just the beginning, but this feeling never fades, every time you put the framework to the test it passes it in a surprising and novel way that was not anticipated before. There was a saying when I was in grad school, the string is smarter than us, that’s probably true…
To answer the original question of this debate, I believe the reason more string theorists have not joined this discussion is that it isn’t a productive use of their time. From my recent experience, I would tend to agree. These sites tend to be populated by a number of people who are more interested in interjecting their own prejudices and opinions than honest debate. How can any string theorist explain why he/she works on it while being screamed and yelled at? The thing it most closely reminds me of is right-wing talk radio. I think the fundamental problem is not any problem with string theory, but rather jealosy of the attention it attracts on the part of the critics and their determination to sully its reputation.