Sunday, July 03, 2011

Jeff Harvey: summary of Strings 2011

Strings 2011 in Uppsala, Sweden is over. Here are the videos sorted according to the speaker.

I decided to embed the summary talk by Jeff Harvey - a co-father of heterotic strings, orbifolds, and assorted solitons and instantons in string theory and elsewhere - because it's fun and comprehensible to semi-experts such as many TRF readers:

Harvey talks about the technical talks about the amplitudes - usually by the younger people and usually somewhat detached from string theory - as well as all kinds of things such as AdS/CFT applied to condensed matter, fluid dynamics, and cosmology; sporadic groups; tunneling in the landscape (Brian Greene's talk was kind of fun and technically fine - but the questions by Juan Maldacena and Greg Moore were even sharper).

Jeff Harvey tends to believe that the N=8 supergravity has divergences at 7 loops (and higher) which probably prevents it from gaining "sainthood" (a funny Catholic discussion) - and Simeon Hellerman (greetings if you read it!) and others believe the same thing. I find it very plausible that they're right - but there could still be more obscure reasons why the divergences vanish to all orders in perturbation theory (but surely not beyond it!).

Harvey also mentions Ashoke Sen's new remarkable checks of the black hole entropy in string theory.

A lot of recent progress is nicely demonstrated when Harvey divides the talks to those that would be recognizable by those who have slept since 1998 - for almost 15 years. He could have also discussed the subset of the talks recognizable for those who have not only slept for 20 years but have been brain-dead since the 1980s - I don't want to enumerate the names of those various Shmoits one after one.

Jeff Harvey mentions a new topic that didn't appear on the conference: the AdS/fluid duality may be applied to see some violations of the cosmic censorship in 5 dimensions where short-scale fractal structures of quantum gravity are not shielded by any horizon.

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