Today there were many talks and I will comment on some of them. For the full list see the program. The first talk was given by Maldacena and was about giant magnons. Since there is a believe that the N=4 supersymmetric gauge theory is integrable there is a lot of activity trying to show that using the AdS/CFT correspondence. For the moment you just find some sector of the gauge theory which can be mapped to a spin chain and look for the corresponding string theory hoping that you can gain some understanding for the full theory.
Feng gave a interesting talk about dark matter and supergravity. After presenting arguments that DM could be composed by gravitinos he said that the LHC could produce long lived sparticles that decay into gravitinos. These sparticles would then be stored in a tank of water and the gravitino properties studied. That is fantastic. Not just susy would be found at LHC but also supergravity! Freedman, Ferrara and van Nieuwenhuizen, who have just won a prize from the American Physical Society for the discovery of sugra, must be very happy.
Herman Verlinde showed how to do string phenomenology bottom-up. Just moosify the standard model. In the panel discussion that happened yesterday he suggested that all smart string theorist should be doing phenomenology because the LHC will start soon. He has a point. We have to understand what will come out of the LHC. But I don't believe many people will change as he changed. Each one has his own recipe for success.
Another good talk was giving by David Tong on how to use string and D-brane techniques to understand the quantum dynamics of field theory solitons.
To those interested I can not google or access wiki in any language.
Tomorrow there will be a tour so there will be fewer talks.
Almost forgot, after dinner we had a special seminar by Yau telling the history of the Poincaré conjecture and how he solved it! Again, high school students in the audience but less than in the Great Hall of the People yesterday. Also a video from Hamilton, a mathematician who participated in the solution, telling Yau's contribution to maths. Quite impressive that China has such a tradition in mathematics. And for the Chinese students, sitting among the scientists of the West, it must have been wonderful to hear that his teacher solved such an important problem. Looks like China soon will take the lead also in mathematics.
UPDATE: I can't answer any comment because I can't access blogspot. So I will answer
Peter's question here. Yau gave a public lecture not a technical one. He mentioned several other mathematicians which also gave contributions to the conjecture and explained what they did. He is not claiming that he did it by himself. I am not an expert on the conjecture so I don't know how fair he was in the lecture. But you know, it was a public lecture and Yau is now regarded as a sort of a hero by the Chinese.