An interesting short interview with Ed Witten in this week’s New Scientist. Mostly straightforward stuff, but it’s always good to hear what smart people are thinking. Witten is spending the year on sabbatical at CERN; like many people, he was sort of hoping to be there when the first physics results from the LHC appeared, but reality intervened an that’s looking increasingly unlikely. Happily, CERN has developed electronic means of communication whereby interesting findings may be promulgated to researchers who are not within close physical proximity to the lab.
Longtime CV readers may be interested in Witten’s take on the String Wars:
The 1980s and 90s were dotted with euphoric claims from string theorists. Then in 2006 Peter Woit of Columbia University in New York and Lee Smolin of the Perimeter Institute for Theoretical Physics in Waterloo, Canada, published popular books taking string theory to task for its lack of testability and its dominance of the job market for physicists. Witten hasn’t read either book, and compares the “string wars” surrounding their publication – which played out largely in the media and on blogs – to the fuss caused by the 1995 book The End of Science, which argued that the era of revolutionary scientific discoveries was over. “Neither the publicity surrounding that book nor the fact that people lost interest in talking about it after a while reflected any change in the intellectual underlying climate.”
That sounds about right. For the most part, actual string theorists simply went about their business, trying to figure out what this fascinating but difficult theory really is. The irony is that a major point of the anti-string books was that the public hype concerning string theory didn’t paint an accurate picture of its more problematic features — which was true. But the backlash books gave the public a misleading impression in the other direction, leading to the somewhat amusing appearance of my own piece in New Scientist explaining that the theory was for the most part chugging along as before. Hype cuts in every direction, and it feeds on drama, not on accuracy.
There is certainly some feeling that the near-term growth area in high-energy theory is not string theory, but phenomenology (or arguably particle astrophysics). Certainly those are the people who seem to be getting the jobs these days. The explanation there is pretty straightforward: data! Or at least the promise thereof. It’s hard to do physics with little to go on other than thought experiments, but one gets by when relatively few real experiments are available. Increasingly, that’s no longer the case.
But it’s been a long time since we’ve had a good string-wars thread, so here you go. For old time’s sake.
“Weeter Poit”
I see, so the way to recognize a good research university with real experts is that it “hires a high fraction of string theorists”. Guess there just are fewer and fewer good research universities all the time…
Re The End Of Science – anyone remember Charles H. Duell (Commissioner, US Patent Office) recommended it be shut down because everything had already been invented – in 1899.
Apocryphal or not, the quote attributed to Einstein iss still accurate:
“Only the universe and stupidity are infinite – and I’m not sure about the universe.”
I stopped reading the nonsense spewed by “Weeter Poit” after this:
Wrong and Wrong and ignorant.
As I understand it, string theory is tied up at least in part with the theory of Galois Representations, automorphic forms, and the Langlands program (see What is a Galois Representation?).
Since these are still largely (mostly?) shrouded in mystery, despite some spectacular results, it’s hardly surprising (on the above assumption) that the same can be said of string theory and therefore premature to write it off.
The Cold War is over. So asking to restart it only make sense if one is looking for entertainment. Likewise for String War.
The String War was decided by evidence, results, and direction – well, lack thereof. The TTWP & NEW books played a large role but one of communication, at the terminal ‘nail in the coffin’ phase. They brought awareness and critical debates to a wide audience on the issue, opened many eyes, the result of which is growing decisions by professionals to seek other areas of research.
Today, quantum gravity (and associated grand problems) are still stuck. Brave researchers continue to struggle mightily. It is even more daunting today as new approaches also met with almost insurmountable roadblocks. This means only one thing – whoever opens the true gate to solve the puzzle will enable a historical new chapter in human history. The discover will be hailed as ‘Einstein Squared’. This is no mere war. This is civilization.
All of these people such as Peter Woit etc. are really fooling themselves by claiming that string theory has gone out of fashion as a result of their criticism and popular books. The only people who actually believe this are crackpots and others on the fringes of science who are engaging in wishful thinking. Almost all new papers on hep-th are string theory papers and most serious high-energy theorists work in string theory. It’s true that hiring has focused more recently on phenomenologists, but this is mostly because of LHC and the promise of data. Once new physics has been discovered at LHC, the hiring will again return to those working in fundamental theory.
“The Next Einstein” said:
“All of these people such as Peter Woit etc. are really fooling themselves by claiming that string theory has gone out of fashion as a result of their criticism and popular books.”
PW said:
“I have no idea how much influence my book or Lee Smolin’s may have had on the decisions of people in the physics community to stop hiring young string theorists for permanent jobs, but I suspect that of far greater influence has been the juvenile nature of the reaction of many string theory partisans to the books.”
TNE, please read more carefully. The difference between what PW said and what you claim he said is very great.
“Guess there just are fewer and fewer good research universities all the time…”
Of course that it’s largely true. A part of it is about the “concentration of intellectual capital”, something that takes place in the economy, too.
In the mid 1980s, Princeton was already on its way to absorb most of the top theorists and become a leader in theory which remains true as of today.
Later, Santa Barbara or Rutgers, the seemingly random 1.5th league universities, led the dramatic progress in the field during the middle 1990s. But it was natural for the 1st (Ivy) League places to regain the leadership. The most obvious method to do so is that they may usually make better offers so they attract the best people – i.e. the best string theorists and a few others.
The 2nd league places must simply be choosing from the rest. There are not too many new people per year who have the ability to become good string theorists.
“I see, so the way to recognize a good research university with real experts is that it hires a high fraction of string theorists.”
It is not “the way” but it is certainly “a way”. Just draw the correlation graph between the general quality of a university, as evaluated by independent procedures, and the percentage of string theorists in its physics department. You will see a pretty nice increasing function. It is no coincidence.
If you want to see a decreasing function, draw the number of copies of the two books available in the university against the general quality of the place. It’s no coincidence, either, because most of the scholars buy these books because they want to calm down their jealousy. Only a conspiracy may explain why they’re not equally successful, can’t it?
Peter Woit said: “I think I’m actually much more sympathetic to his current research than the rest of the particle physics community is. ”
You certainly got that right. Most of us wish he would resume his much-needed leadership role. Returning to actual physics from boring technical exercises with “GOING NOWHERE” painted on them in large letters would be an excellent start.
Ree Ree brings up a great point.
There was this Cro-Magnon Og who was truly one of the most remarkable stone polishers to ever have emerged. One day he was summoned by Ug the Great about an opportunity to be Ug’s personal stone polisher (and no jokes by you mound builders, stone polishing is the highest skill of cave dwellers). I just happened to be passing through when Og was talking to Ug, and so just as a little joke, while Ug was looking the other way, I smashed Og’s toe with a sloth mandible.
I have never seen Og get so mad!
Needless to say, after Ug saw Og’s juvenile behavior of screaming and jumping, Og just didn’t have a chance at the position. Ug’s decision was valid of course; who wants to be seen with a Cro-Magnon that out of the blue starts raising a ruckus?
As a side note, as a response to TimG’s question, the answer is yes, I commented correctly.
I also must agree with Peter and Follower that the world would certainly be better if Witten was implanted with a remote so we could get him to work on the projects that interested us and not the projects that interested him.
“Weeter Poit”
OK, I get it, you’re parodying the attitudes of string theorists. Very funny.
What gave it away was the claim that Princeton was a backwater, didn’t become a leader in theory until the mid-eighties when it started hiring string theorists. Sorry, but if you want to fool people, you can’t go over the top like that.
To suggest that grad. students are not into string theory these days is either ignorance or an active effort to mislead the public. The reality is in fact quite the contrary: as Sean points out, senior people including (surprise!) “string theorists”, prefer to hire phenomenologists/cosmologists over formal theorists these days because of data from WMAP+LHC. But despite this, the number of students who want to want to work on fundamental theory seems unchanged, at least everywhere I know.
jamie,
I agree that there continue to be a large number of students who want to work on fundamental theory, but I do think that the number who, like you, identify “fundamental theory = string theory” has declined. Just about anywhere, I’m sure one can find students entranced with string theory, as well as ones who hate it. The ones who care about their job prospects though are going into cosmology and phenomenology.
I don’t think there’s actually any evidence that WMAP data (now old news) or LHC data (non-existent) is what’s driving the job situation of the past two years. One significant effect of the LHC that I’ve heard about from several people is that the following argument is being made in faculty meetings: “string theorists keep telling us to wait for the LHC, which will discover supersymmetry and vindicate them, so, let’s not hire in that field now, but wait a couple years and see what happens.”
Peter, has it ever occurred to you that the anonymous masses who are constantly whispering into your ear about the decline of string theory might not represent a truly unbiased sample of people in the field?
The idea that the job situation is not being driven by the prospect of LHC data is completely divorced from reality.
Alex,
I’m as skeptical as anyone about anecdotal information, but I think that if you believe there’s not now a widespread perception among physicists and the public at large that string theory has fallen on hard times, you’re completely divorced from reality.
Evidence about this comes not from anonymous masses whispering in my ear, but very public sources. For instance, I was just listening to the Science Friday broadcast last week from the ASU Origins symposium. It featured Ira Flatow asking Brian Greene what he thought about the perception that these were hard times for string theory. It’s not hard to find many other such examples.
The “prospect for LHC data” has been there for quite a few years now: planning of the machine started about 25 years ago, construction was approved 18 years ago, and began 11 years ago. For a while, it was supposed to start taking data in 2005, four years ago. Sure, the LHC is one reason for the move to hire phenomenologists rather than formal string theorists, but that reason has been there for a long time, and doesn’t explain the dramatically worse job market in string theory of the past two years.
Peter, I don’t know what you mean when you say that many students are calling something other than string theory (LQG? DSR?…) as the “fundamental theory” these days. This certainly does not match my experience at all, and I don’t even know what theory or theories you are talking about, basically because there are not many alternative approaches out there which are even moderately successful.
Also, I think the burden of evidence is on you, if you suggest that the reason for hiring phenomenologists in the era of LHC is something other than the LHC. I honestly do not understand why it is useful to hire phenomenologists long before the LHC start up, even if the plan was in place for 25 years. The hiring increase in the last years is precisely correlated with the fact that people have been expecting LHC to turn on somewhere around 2005+.
Woit said, “I don’t think there’s actually any evidence that WMAP data (now old news) or LHC data (non-existent) is what’s driving the job situation of the past two years.”
If you want to make predictions about what LHC will see and get your guys in place, you do it before you have data not after. Apparently Woit has no idea how things work in the real world.
I guess I’ll let “jamie” with his “I honestly do not understand why it is useful to hire phenomenologists long before the LHC start up” argue with “The Next Einstein” and his “If you want to make predictions about what LHC will see and get your guys in place, you do it before you have data not after. Apparently Woit has no idea how things work in the real world.”
If either of you read what I wrote:
“LHC results were a couple years away three years ago, they’re still a couple years away”
you’d notice that the point is you can’t explain a dramatic shift in hiring that has taken place during the past two years in terms of a phenomenon that has not hardly changed at all for the past several years.
By the way, do any of you people have real names? I’m sorry, but I can’t get over the idea that only an adolescent would write comments pseudonymous comments on a blog calling themselves “The Next Einstein” and telling others they have “no idea how things work in the real world”.
I personally think there is no correlation with the rise of phenomenology hiring and the intellectual merits of string theory as percieved by department heads.
The former would have occured in the era of the LHC even if string theory was going through another revolution.
The drop off in jobs in string theory otoh, is more closely related to the difficulty of actually making progress atm. The easy readily solvable problems have been by and large exhausted, and its more and more difficult to actually solve things relative to what it was like in the 80s and early 90s. That doesn’t mean its a deadend, i’d say the immense majority of grad students and faculty in HEP are still very pro string theory.
15 years ago the expectation was “Witten will reveal us the Ultimate Truth and LHC will measure details of supersymmetry”.
As LHC is coming, we realized that string theory has no predictive power and now our best hope is making progress in the usual experimental way: LHC is finally coming we don’t know what it will find.
String theorists smarter than string theory moved to phenomenology.
It seems strange to me that after so many years and effort, string theory could just fade away. It would be certainly one of the biggest fiasco in human progress. The fact that there are no experimental predictions right now doesn’t mean that you’ll have to abandon the entire theory especially if there are good theoretical reasons not to. I feel that the physicists often exaggerate regarding predictions and experimental verification. It reminds me what we engineers do sometimes using reverse engineering. If you don’t know how a system works and you don’t understand its basic principles you take it apart and you put it to the test to comprehend it. Generally reverse engineering is a bad thing since it reveals a complete lack of knowledge regarding the fundamental principles of the underlying theory of the system. In rough terms and if we assume for example that nature is that system then I could say that with LHC you just take it apart to find out how it works. That’s reverse engineering.
So the point I want to make is that if you are confident about your theory (its basic principles and mathematical structure) stick to it even if you don’t make any experimentally testable predictions for the time being. If you are willing to give it up so easily, it means that you don’t know what you are doing.
My impression matches that of Haelfix. Work on phenomenology/cosmology is likely to pay huge dividends, whereas work on string theory is chugging along at a lukewarm pace. This easily explains the hiring trends, even if you are too cynical to take the word of the people (including string theorists) who do the hiring. Woit’s claim that there is a “widespread perception among physicists” that “string theory has fallen on hard times”, is either ignorance or propaganda – at least if you are talking about physicists in the HEP community. This is what Witten (Woit’s hero) says in his quote, and this is what is obvious to anybody who is from within the community.
“jamie”,
When the biggest propagandists for a theory describe the situation as “chugging along at a lukewarm pace” or “it’s more and more difficult to actually solve things”, that’s a situation that non-propagandists describe as “having fallen on hard times”.
sheesh.
Regardless of who is actually right, from reading the above it seems to me that Woit is the only one who has formed a coherent opinion and is capable of arguing it.
{[(-Slightly modded from my original; -this was a Michio Kaku -FanClub / yahoo-group Posting, -&, this -just the poem without the stringy backdrop jpeg-)]}
THREE STRINGS FOR TEN-THOUSAND-THINGS UNDER THE SKY,
SEVEN FOR DETERMINISTS IN THE HALLS OF STONE,
NINE FOR MORTAL MIND DOOMED TO PI,
ONE FOR THE QUARK LORD ON HIS QUARK THRONE
IN THE LAND OF M-BRANE WHERE THE THEORIES FLY.
ONE STRING TO RULE THEM ALL, ONE STRING TO FIND THEM,
ONE STRING TO BRING THEM ALL AND IN THE QUARKNESS BIND THEM
IN THE LAND OF M-BRANE WHERE THE THEORIES FLY.
… Vex Vuthor /aka/ Doctor Static …