Musings

Ooguri, Kachru and — to a lesser extent — Douglas focussed on supersymmetry-breaking. The big breakthrough, of course, was the realization that long-lived metastable SUSY-breaking vacua are good enough for our purposes, and these are much more readily available than theories with no SUSY vacua.

The most interesting part of Kachru’s talk was his discussion of the realization of conformal sequestering in a stringy context. Probably, a proper discussion of that will require another post, starting with a review of Schmaltz and Sundrum.

Beisert and Zarembo talked about integrability in large-$N$ $\mathcal{N}=4$ Super Yang Mills, and in the dual AdS string theory. Beisert’s talk featured considerable progress towards an all-orders conjecture for the scaling dimensions of operators in the CFT, and completely illegible formulæ on his slides.

Roberto Emparan gave a very nice review of the status of rotating black holes in higher dimensions. In 4 dimensions, there are theorems which give a unique steady-state configuration for given blackhole mass, $M$ and angular momentum, $J$, and an upper bound on $J$, for fixed $M$. Already in 5 dimensions, there are black rings (horizon topology $S^1\times S^2$ instead of $S^3$). So that, for some range of $M,J$, there are three configurations (two stable) for given $M,J$.

When you go to $d\geq 6$, things get even worse: there’s no upper bound on $J$ (this results from the obvious observation that the centrifugal term in $$-\frac{G M}{r^{d-3}}+\frac{J^2}{M^2 r^2}$$ wins for $d\geq 6$) and it’s not even known what the range of possible horizon topologies is.

And then there was Riccioni’s talk on $E_{11}$. Dunno what to make of that …