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It was started back in by C. Yang and has been an active center for theoretical physics ever since. I was a postdoc there inwhen it was just the ITP, and Yang was still the director. I had been hoping to go out to Stony Brook for at least one day of the event, but unfortunately other things have kept me here in New York. Being able to talk to and learn from some great mathematicians soon after Yang, in Jim Simons came to Stony Brook and brought together a world-class mathematics department was a big influence on me during my postdoc years.

These days, with the Simons Center for Geometry and PhysicsStony Brook is one of the great centers of mathematical physics. My time at the ITP coincided with the early years of this kind of string theory hype, which got started in lateabout the time I got there. By my last year there exactly 30 years ago,everyone in the physics community had already been subjected to a couple years of this kind of thing, so much so that Ginsparg and Glashow had published in spring their Desperately Seeking Superstrings article, noting that.

Contemplation of superstrings may evolve into an activity as remote from conventional particle physics as particle physics is from chemistry, to be conducted at schools of divinity by future equivalents of medieval theologians. My own attitude at the time was that superstring theory was just one in a sequence of fads that had gotten the attention of particle theorists, with one to two years the usual decay time for such things.

So byI figured this one was now past its sell-by date and would soon be on the way out. How wrong I was. As I sort of remember it, there were major issues with various singularity sort of issues, and then Witten figured out ways around them, and things took off again, getting much worse when Malcedena came along. I of mors olive meta lab correction bit never knew the details, being a mathematician, but I mors olive meta lab correction bit it a little since I knew Witten as a mathematician, a very good one.

In this other sector of the multiverse, who might you be in ? M-theory in the mids really revived and changed a lot the nature of what string theorists were doing. You can say whatever you want about string theory as a model of particle physics. The study of string theory, especially afterhas been the single most fruitful source of new toy models, new mechanisms, and new ideas in QFT. But the general picture is a decline, as you say, compared to its glory days of Making QFT research an appendage to string theory research means that certain aspects of QFT have gotten a lot of attention and made progress e.

As an example of what I mean, I was referring above to the amazing breakthroughs in our understanding of QFT that Witten came up with especially Chern-Simons, TQFTs during the late 80s, early 90s, many of which had nothing to do with string theory. Yes, you would lose all sorts of things that came out of that, but perhaps the QFT research directions that people followed instead might have been even more interesting.

I think that slide does a good job of measuring the popularity of string theory. It was at its height inreached a local minimum aroundrevived for a while, and has been steadily decreasing since Sometimes we can even reduce it to something mathematicians can work with. Witten was working on topological QFTs because he was looking for simplified models that exhibited background independence, so that he could better understand string theory! Other lines of inquiry on mors olive meta lab correction bit sigma models and mirror manifolds are explicitly string theoretic.

Likewise, the Seiberg-Witten revolution in differential topology was really spin-off of spin off of non-topological string theory calculations. AJ, Your claims about history really are just not mors olive meta lab correction bit. I was there at the time, and later I spent a lot of time carefully researching the details of this history before I wrote about it in my book. One place where Witten tells the story in his own words is here: Witten was undoubtedly hoping that the ideas about QFT he worked out in the TQFT paper would lead to some new insight about string theory.

The flow of information though was opposite to the one you suggest: As for his Chern-Simons paper, sorry, that had nothing to do with string theory either although it did have to do with the WZW cft. Fortunately, we do have the original article, where he points out that the core arguments are analogous to ones already known in string theory.

For those who care, see http: One correction to the history you give in your link: I was a bit surprised that the only question Witten had during question time at the end of my talk was matters pertaining to higher genus — a question only a mathematician or a string theorist? How do you think Mors olive meta lab correction bit duality would have fared without the work of Sen, whom you just managed to be breathtakingly disrespectful to.

You know Mors olive meta lab correction bit usually do not comment in this forum, but the discussion is interesting in this case. Except for the analogy with the phases of water, there is not much. But may be that is his view of that part of String Theory.

If one reads the second part, the thing takes a much more interesting perspective. In particular, Sen discussed the virtue of the black hole as an ideal system. This lead to remarkable progress. I just felt that your comment about his talk was unfair. May be I am biased by the fact that knowing Sen, having discussed with him in few occasions, I clearly have the perception that he is a very deep thinker, who truly cares for his research and the truth in it.

Aside from a very nice person. I know I am mixing things here, so just wanted to stress that the second part of his seminar was much more insightful. You are saying in one of your responses to the commenter AJ that: On which mors olive meta lab correction bit agree. Of course, we do not know and we cannot know. But, I know you appreciate the fact that the theory of strings, dealing with very symmetric systems, has a high chance of striking a discovery.

Seiberg duality, the Seiberg-Witten solution are such examples though not so good, as there is a stringy taste to them. Importantly, these ideas found a very nice and intuitive realisation in stringy language brane set ups, etc.

Other important advances in QFT—like the Maldacena conjecture—seem harder to come by if one is not working on strings. All I am trying to say a bit obvious, I believe is that being so symmetric, String Theory suggest ideas that then might find interesting applications in QFT in general. I believe we will agree on this virtue of the theory of Strings. About the String Theory being a description of physical Nature, I am saying nothing here. Just about its ability to struck on interesting aspects of QFT in general.

My comments about this were about two very specific advances in QFT made by Witten in where the situation is rather simple: That he is likely not aware of them does not change the problems with the talk. Where what never lived can never die Uncommon Descent. Not sure when I read it though I suspect via a PW link at least a decade ago. But thanks to you and PW I have reread it.

Glashow was my favorite professor during my brief foray mors olive meta lab correction bit HEP-th 40 years ago. Even those who are dismissive of String Theory will have to grant that. He, as someone commented above, is undoubtedly a deep thinker.

But beyond that he is an unassuming and self-effacing person of a truly rare kind. Only other physicist with similar qualities who comes to my mind is perhaps Jeffrey Goldstone — my teacher at MIT nearly four decades ago.

Ashoke believes that potentially deep theories must be explored thoroughly to see what they have to say about the world. It is a fortunate thing that he has decided to deploy his remarkable talents to this end, as must also be mors olive meta lab correction bit about Witten. Everyone knows that the twin goals of String Theory — understanding the success of the Standard Model and arriving convincingly at Quantum Gravity — have not been mors olive meta lab correction bit so far.

I am sure leaders of the field including Ashoke are more aware of this situation than anyone else. There may be many string theory enthusiasts who may be prone to hype.

But names like Ashoke Sen and Edward Witten should not be dragged into the mud. Smart, nice, unassuming people can be wrong about things, and, at times, this needs to be pointed out.

He seems to describe compactification as the shrinking of 6 dimensions. Is that actually what physicists mean by compactification? Am I misreading the slides? Is he saying that we shrink the dimensions by turning them into circles?

So how is it relevant? They use this just to mean you are looking at a theory on a pseudo-Riemannian background manifold that is Minkowski space or some cosmological background times some Riemannian manifold M.

It may be smooth and compact, but also could be singular and non-compact. Typical models also add lots of other structures to M e. Mencken was caustically cynical about atoms, quantum mechanics, and relativity….

It just really confuses me, why anyone mors olive meta lab correction bit about it. And mors olive meta lab correction bit for clarifying about compact. I imagine the specific objections to string theory have not changed much over the years and so have been thoroughly discussed in the annals of this blog. Which means that you could probably just link the time frames to old threads.

Just my two cents. I might as well illustrate precisely what I meant by a specific criticism of Mors olive meta lab correction bit, here is a link to the video at the precise moment the 1: I spent a couple years writing a book addressing these issues in detail and explaining what the problems were with the conventional string theory hype.

Sen is just repeating pretty much the same hype the book was aimed at. No sensible person wants to read yet another explanation from me of why string theory unification has failed and why the string landscape multiverse is pseudo-science. In some sense what I write here is aimed at them: Of course, you know how best to spend your time rather than me.

It just seems that there is enough energy spent going back in the forth in the comments that a mors olive meta lab correction bit investment along the lines I suggested might be worth considering.

It was just a thought.