Last week the CUNY Graduate Center hosted a conference in honor of the 75th birthday of Jim Simons. It was organized by Dennis Sullivan as a set of expository “mini-courses” on various topics related to Simons’ mathematical work. I was able to attend the morning talks, which were of a uniformly high quality, and focused on the Chern-Simons 3d QFT, as well as the “differential characters” of Cheeger and Simons. Video of most of the talks is available online here. In particular, Witten’s talk, which was a very simple physical introduction to use of the Abelian Chern-Simons term in condensed matter, is available here (followed by Deligne on Deligne-Beilinson cohomology). Talks by Robbert Dijkgraaf on Chern-Simons-Witten theory are here and here. The second Dijkgraaf talk was followed (go to 1:05) by some informal comments by Simons himself, explaining the history of how Chern-Simons came about. Mike Hopkins gave two wonderful talks, the first about differential characters in general and about his recent article with Dan Freed, the second about his work with Singer that used generalized differential cohomology.

The talks I missed were likely just as good, I’m starting to catch up on them on video now….

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I worked with Jim for 15 years, most of it as a Managing Director at Renaissance Technologies. As Chairman and President, he not only guided the overall research program but made many seminal contributions himself. Jim was far more than a brilliant researcher. Renaissance’s success can be directly attributed to the environment he created. Jim built a place where integrity, respect, and creativity were nutured and supported. All of us bright boys and girls had pretty healthy egos, but it is hard for anyone to play the prima dona when the boss, who managed to think rings around the best of us, was just so damned decent. Jim taught me that the pursuit of excellence works best when put first the people whom you expect to achieve it.

Hi Peter,

I was asking you about a research paper you were working on way back in 2008:

http://www.math.columbia.edu/~woit/wordpress/?p=673&cpage=1#comment-36511

You said you are still working on it, did I miss anything?

Or is it already posted/published somewhere?

Best wishes,

Lloyd

Lloyd,

See this

http://www.math.columbia.edu/~woit/brstdirac.pdf

I’ve been intending to get back to work on this, for the past year have been working on the notes posted here

http://www.math.columbia.edu/~woit/QM

Hope to finish this project this summer, then get back to the BRST/Dirac Cohomology project.

Thanks Peter for the links!

The cohomology project seems very interesting, but the date on the notes is 2009!

Why not go ahead and publish whatever you have now? You can always submit follow-ups later. I guess this would put to rest the assertion that you do not actually do any fundamental research.

Best,

Lloyd

Lloyd,

The paper is on my web-site, I wrote about it on the blog, it should show up quickly if anyone googles for information on that topic. Honestly, very few people seem to be interested in it. I definitely need to get back to work on the paper, produce a more complete version including what I’ve learned in recent years, and that I’ll likely publish somehow, or certainly make a serious effort to get others interested in.

For now, I’m working hard on the book, and that actually should be very helpful for the Dirac cohomology/BRST paper when I get back to it. There are a host of tricky technical details I hadn’t gone through that writing the book has made me sort out. So, maybe a draft of the book will be done this summer, new and improved paper this fall. We’ll see..