## Wednesday, January 21, 2009

### Klebanov and Maldacena about hyperbolic cows

In the new issue of Physics Today, Juan Maldacena and Igor Klebanov write a semi-popular "feature article" about the 11th anniversary of the AdS/CFT correspondence:
Solving quantum field theories via curved spacetimes (PDF)
One of the way to describe a negatively-curved space (in this case the Euclidean AdS2, or the Poincaré disk) is in terms of hyperbolic cows:

Physicists have been using spherical cows as an idealization of the real ones for centuries but only at the end of 1997, they finally discovered another comparably important idealization, the hyperbolic cow. Well, if these comments sound less technical than expected, you should prepare for the rest of their article that could be more technical than expected.

Also, in The Independent, Michael Duff recently tried to explain why theorists are so excited about string/M-theory. Meanwhile, Nastya Volovich received a prestigious award in the White House, as another Mr Klebanoff reports. Congratulations to a highly deserved one!