One of the weirder things that happened yesterday was that I noticed there was a long thread in a discussion group about my academic qualifications. You can find this at

Physics Forums

My academic career has been a bit unusual, and the current position I have at Columbia is kind of confusing, so for those who want to carefully examine my qualifications before deciding whether to take anything I write seriously, here’s a short outline:

1979: B.A. and M.A. in physics, Harvard University. As an undergraduate spent one summer working on a particle physics experiment at SLAC.

1984: Ph. D. in theoretical physics, Princeton University, advisor Curtis Callan, thesis title “Topological Charge in Lattice Gauge Theory”.

In my thesis I developed a workable way of calculating the topological charge of lattice gauge fields and did Monte-Carlo calculations using it. This led to joint work with collaborators including N. Seiberg at the Institute in Princeton and about seven published papers on the subject in the mid to late-eighties.

1984-87 Postdoc at the Stony Brook ITP

Got interested in spinor geometry,TQFT and representation theory, started talking to a lot of the mathematicians at Stony Brook

In 1987 it became clear to me that someone who didn’t believe in string theory but wanted to apply mathematics to QFT didn’t have much of a future in physics depts in the US. I spent 1987-88 as an unpaid visitor at the Harvard physics dept., earning a living teaching calculus in the Tufts math department.

1988-89 Postdoctoral fellowship at MSRI in Berkeley. Published a couple papers on spinor geometry and the standard model, TQFT and representation theory.

1989-1993 Assistant professor, math department, Columbia.

This wasn’t a tenure-track position, so at this point I needed to find a new one and my current job became available in the math department. It is an unusual, “off-ladder” untenured but permanent position with the title “Director of Instruction”. Its responsibilities include administering the dept computer system, teaching a course each semester, and participating in research activities of the department. I’ve held this position for ten years.

It should be made perfectly clear that I’m not a regular, tenured professor at Columbia and have never claimed to be. On the other hand, I’ve spent a lot of time learning mathematics, often by teaching it. I’ve taught many of our undergraduate courses and some of our graduate courses, including Representation theory and QFT for mathematicians.

So that’s my weird academic background and status. make of it what you will.

Personally I feel rather lucky at how this has turned out. It all started with having relatively well-off parents who could afford to send me to Harvard, I then enjoyed about the best education in particle theory possible, and now I have a permanent job surrounded by very talented people that I like, one that gives me a fair amount of time to think about what I choose. Anyone who thinks I’m an embittered soul doesn’t know me very well. While I’ve seen a lot of talented people be badly treated by universities and by the atrociously bad job situation in many fields, I don’t have anything to complain about.

One problem with this is I don’t know what career advice to give young people interested in particle theory. They’d be fools to do what I did, but if they follow the standard path they’ll probably get screwed. It seems to me that a very big question the particle theory community needs to be addressing is how to provide a career path for really smart students that gives them encouragement to strike out in new directions, with a viable chance at making a permanent career of it. Right now many of the young people in the field I talk to are very discouraged, feeling that their choice is to either try and make a name for themselves by working on a not very promising but trendy string theory topic, or to commit academic suicide by trying something different that probably won’t work out. This situation is extremely unhealthy.

Hi Pyracantha,

It’s hard to talk about physics in general, different subfields have different things happening in them. As far as particle physics goes, progress has undeniably slowed in the past 25 years (people will disagree about how much…) for two overriding reasons:

1. The standard model is just too good, making the field a victim of its own success. It was in place by the mid-seventies and all experiments agree with it (or to be precise, with a slight extension of it to include neutrino masses). It’s vastly harder to come up with good new ideas about physics when you don’t have experimental results that conflict with theory and point you in the right direction to improve the theory.

2. Available accelerator technology is reaching its limits: there are diminishing returns and going to higher energies is more and more difficult and expensive. There will finally be a big new jump in energy at the LHC in a few years, but both political and financial problems have caused this jump to be a long time coming.

Hi Erin,

I spend most of my time among mathematicians, so I’m very aware what they think of QFT and string theory. With few exceptions, they’re pretty confused about the distinctions between QFT, string theory, supersymmetric QFT, etc. They generally see all of these as one uniform, mysterious set of methods that undeniably has lead to some fantastic mathematics. This isn’t really surprising: these are complicated ideas, with complex relations between each of them and between them and more standard mathematics.

So, they’re often surprised to hear me criticizing string theory, saying “but it has lead to so much great math!”. To a large extent this is right: string theory has lead to some great math and in many ways its influence on math has been very positive. Unfortunately many mathematicians believe that everything that has come out of physics came out of string theory, believing for instance that the work that Witten got the Fields medal for was string theory. It’s hard to explain to them that many things like this came out of QFT, not string theory. It gets even more confusing since some of the most interesting math has come out of conformal field theory, which is both 2d QFT and a crucial part of perturbative string theory.

Personally I’m pretty convinced that, while good mathematics will continue to come out of string theory, QFT will ultimately have an even bigger impact on math. QFT involves mathematical structures that are infinite-dimensional examples of structures that are well-known to mathematicians in the finite dimensional case. Mathematicians often hadn’t thought too hard about how to generalize to infinite dimensions, because typically there are many ways to do this and, until QFT came along, it wasn’t clear which if any ways lead to something interesting. Even after getting guidance from QFT about which way to go, it is still very difficult to rigorously deal with these infinite dimensional things, so mathematical progress is frustratingly slow. If the study of QFT in physics was in a healthier state, there might be even more fruitful interchange between math and physics than there is at the moment.

Is there a sense of “diminishing returns” in current physics research – more studies and more theorizing, but fewer results and less ability to verify by experiment?

Pyracantha

“Hype” indeed. String theory thrives upon hype and media attention in my opinion; for example, Greene’s `The Theory of Everything’ TV series recently shown here [known as `The Elegant Universe’ in the U.S.]. Topics like the Standard Model just aren’t the sort of thing people wish to popularize into TV series.

I recently read a mathematician refer to string theory as a particular quantum field theory (but perhaps he meant string field theory instead of string theory…?), and seeing any success – past, present or future – in string theory is difficult. Yes, I too hope things will change for the better. Surely the study of QFT is far from over, and is really only just beginning, for both physicists and mathematicians.

Incidentally, I thought Carlo Rovelli’s `A dialog on quantum gravity’ provided an excellent catalogue of many of the things string theory keeps on not doing and highlights many misconceptions surrounding the alleged successes of string theory. I especially liked the way Rovelli included a debunking of the claim that the Veneziano amplitude is `correct’ (not something many string theory papers discuss these days, I suppose).

Erin

P.S. I would leave a valid e-mail address, but one never knows who’s reading this (anyway, I’m not actively involved in academic research).

Hi Erin,

It seems to me that situation in the US is polarized in exactly the same way as in the UK. To an increasing extent, this seems to be the case around the world. Globalization also applies to particle theory, I guess.

The standard story you’ll get from string theorists is that QFT is essentially a closed book, and that everything interesting about it is known. From their point of view, someone wanting to work on field theory is either too much of a wimp to do string theory, or just too ignorant to realize that everything of interest about field theory has already been done.

This point of view makes sense if you believe the hype that string theory is a successful extension of QFT that explains all the things QFT can’t. When and if people realize that string theory actually doesn’t live up to its hype, maybe things will change.

I think the situation now is very analogous to what happened in the late 60s, early 70s. Most of the leaders in particle theory had abandoned QFT and were doing S-matrix theory (and later, string theory). The few people like Veltman still doing QFT weren’t taken very seriously, I’m sure many people explained to him why he was a fool to work on quantizing and renormalizing non-abelian gauge theory. This all changed with the advent of the standard model, one can hope that a similar shift will happen again in our lifetimes.

Hello Peter,

Ever since `String Theory: An Evaluation’, I’ve made sure I read your articles and papers, and only a few days ago I discovered that you had begun a weblog: it’s marvellous and fascinating, and I certainly agree with your views on string theory.

I myself am a British, disgruntled former particle theory postdoc, and I can relate to your comments on young people entering – or attempting to enter – the field of particle theory research. My PhD research was concerned with field theory, and I wished to continue with field theory research, but found that the opportunities for that in the U.K. were far more limited than I had expected. Increasingly left out in the cold, and struggling to do something which might earn me another postdoc in field theory (which no one seemed interested in), I was dropped and now consider myself a failure. I do wish I could have continued.

To me, there seems to be a stark choice those interested in particle theory research have to make: do phenomenology, or do string theory. This is the message I received during my time in research. Perhaps if I had chosen one of these, instead of being interested in field theory, I might still be a postdoc.

It would seem that if you choose to do research in field theory or mathematical physics – or indeed anything other than phenomenology or string theory – one has to be prepared to work towards either string theory or phenomenology, for doing anything else seems to offer no stable, long-term employment or any career development prospects in particle theory research. Why is it that present (U.K.) research in particle theory seems to be so polarized? Is it the same situation in the U.S., or even worldwide?

Incidentally, during my PhD, my field theorist supervisor was just beginning to turn into a string theorist, and now the transformation is complete. It was a rather discouraging thing to see. I do wonder if he felt pressure to migrate to string theory in order to remain in academia.

Erin J