20 June 2006

Strings 2006 - Day 2

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.

8 comments:

Peter Woit said...

Did Yau really claim that he was the one who solved the Poincare Conjecture? If so, that would be seriously misleading.

s.chan said...

your question is very negative implicitly. it is very unethical and thus it is not fair to prof. yau. he is a very brilliant(please read prof. hamilton's comments), hard working, and always enthusiastic to help young mathematicians. prof. zhu (majoring in pde)studied conjecture related material for 5 years and expected to have a short meeting with prof. yau in hong kong. prof. yau enthusiastically spent 21 days to guide him into this field. also, prof. cao was his student. prof. yau is really a great force of solving the conjecture behind the scene. we are proud of him. please stop attacking him.

Anonymous said...

The question is perfectly fair to Yau. Everyone agrees that Yau is a brilliant and important mathematician (much more so than Perelman, Hamilton, Zhu or Cao), but the Chinese news coverage is ridiculous. The question is whether that is because Yau is distorting the truth for a Chinese audience, or because Yau is presenting it fairly but the local media has no interest in any aspect except the involvement of Chinese mathematicians. I don't know (I know Yau but haven't talked with him in months), but it's a perfectly reasonable question.

John Baez said...

Victor Rivelles wrote:

... we had a special seminar by Yau telling the history of the Poincaré conjecture and how he solved it!

Peter Woit wrote:


Did Yau really claim that he was the one who solved the Poincare Conjecture? If so, that would be seriously misleading.


S. Chan wrote:


your question is very negative implicitly. it is very unethical and thus it is not fair to prof. yau. he is a very brilliant (please read prof. hamilton's comments), hard working, and always enthusiastic to help young mathematicians.


That's true, but he didn't "solve the Poincare conjecture". One often sees Perelman and Hamilton getting most of the credit for proving the Poincare conjecture. But Zhu Xiping and Cao Huaidong have recently contributed crucial work.

You can see what Xinhua and
The Epoch Times have to say about this. They don't say anything about Yau having solved this conjecture, though he is quoted in these articles. In Xinhua, Yang Le says "All the American, Russian and Chinese mathematicians have made indispensable contribution to the complete proof."

Victor Rivelles said...

Dear John,

As I said in my reply to Peter (see the update), Yao didn't claim that he solved the conjecture alone. He mentioned the works of Perelman, Hamilton, Zhu and Cao. That is why I was surprised by the level of Chinese mathematicians.

In my post, when I said "how he solved it!" I really meant how he contributed to the solution.

Best regards.

Anonymous said...

There was an interview with ST Yau on Qiao Bao (Chinese Overseas Newspaper), the media has little or no comments on the Poincare Conjecture and its solvers. It was question and answer type. Yau did claim that he was ONE of those who contributed to the Poincare Conjecture. But he did NOT CLAIM that he solve it. However, in another interview and talk, in which he composed a very beautiful poem (at least it's interesting poem) that describes his efforts and fascination in Poincare Conjecture. For contribution percentage, he modified a little in the QiaoBao, he probably didn't make clear before that: CHINESE MATHEMATICIANS'S TOTAL CONTRIBUTION TO THIS WHOLE WORK [Poincare Conjecture? or Topology or Ricci Flow or Geometrization? I do not know] IS NOT LESS THAN 30%. Previously, I read on a newpaper that quoted as Cao and Zhu's work takes about 30% of the credit. But this is probably a loose statement and not what Professor Yau meant; I don't think he intend to mislead the media.

I agree that since Professor SS CHERN passed away, Yau is the single most influential Chinese mathematician. Tian Gang seems to be very prolific and able mathematician too, but his influence can not yet match Yau's. You can go to math Genealogy and check out Professor Yau's students--most of them are very successful mathematicians on their own. I think Yau would probably get the Wolf Prize soon. Among all the Fields Medal winners, only Yau have so many successful students. Mathematical Monster--an nick name that some of us assigned to Professor Thurston for he's such a haughty genius and polymath that most of us envy yet respect. Read this http://www.news.cornell.edu/chronicle/02/11.21.02/Thurston_profile.html
Thurston is one of the few who received the Alan Waterman Prize, the first one being Fefferman. Other receipients are Gang Tian, Edelsbrunner, Emmanel Candes, Friedman. But the only ones who are of the same rank as Thurston are the undisputed (genius and polymath): Bombieri, Charles Fefferman, (Bourgain?). However, all four of these geniuses do not have as many successful students as Yau, though Thurston has done better than the other three genius-polymathes, and has Kerkoff, Gabai etc being the most outstanding ones. Probably geniuses are just concentrating on their own work and have not met the right students of their expectation and have high expectation with their students, who knows. Sometimes working with a genius can hurt your feeling of being an ordinary scholar :P But anyway, hey, less than 2 weeks left for ICM...I am so looking forward to it!!!Everyone says Terence Tao and Perelman are on the Fields Medal list, we'll see

Anonymous said...

S. Chan. When being fair and trying to find out the truth, there is NO ethical issues attached--people just want to know the truth. I am an as good Chinese as you are S. Chan. But sometimes we need to be unbiased, that we can grow stronger.

Anonymous said...

Everyone agrees that Yau is a brilliant and important mathematician (much more so than Perelman, Hamilton, Zhu or Cao),

Is that a fully Boolean assertion,
i.e. say Yau is much more important than Perelman et al AND Yau much more brilliant than Perelman et al?

But hey, you probably could be given the benefit of the doubt on the subtle points of diplomatic communication in a second language.