Everyone addresses the authors as Ms. Nasar and Mr. Gruber, because they do not hold doctorate degrees. I think it’s fully respectable for them. It would be nice to call Givental as Professor, but the New Yorker article itself just refers to him as plain Givental as well as Perelman. ]]>

Yau is modestly Dr.

Witnesses Hawking, Cao, Zhu, Hamilton, Manin, Liu, Gathmann, Anderson, Shoen are Professors.

Behind the bars, we have: titless Givental, Ms. Nasar, Mr. Griffiths and even Mr. Perelman. ]]>

Thanks for your comments, it may be the case, I’m just saying what I saw from searching the web. Do you have a link to what Chern said about Yau, or what Yau wrote to Jiang.

]]>How do you know there was no conflict between Chen and Yau? Yau will do anything in Chen’s later years because he didn’t need to fear from Chen and he wanted Chen’s blessing so he can be his heir that’s why he kissed up Chen’s ass. I heard many rumours about Yau and his relation with Chen. I don’t think they come from nowhere. I don’t think the New Yorker article has no evidence about this before it was put in print. I heard a famous comment from Chen that, in trying to praise Yau, Chen said Yau could be another Hilbert. But later on Chen himself realized that Yau’s goal was rather to be Chairman Mao. Yau is a very capable and very ambitious person. In a Chinese website, Yau’s letter to former Chinese President Jiang was posted, in which he really kissed up to Jiang’s ass and showed Jiang the poems he wrote in which Yau said he was aspiring to contribute to his motherland (even if I think he is an American, but just wants to rule China, or at least in China’s Mathematics world). ]]>

Nasar describes Yau as having a conflict with Chern, trying to supplant Chern’s status. She uses a quote from one of Chern’s relatives. She also gives the example of Yau fighting against Chern by trying to move the IMU congress from Beijing to Hong Kong.

The relative may not exist, according Yau’s letter. The IMU congress story is also very suspect, if you look at the letter and news links posted on the New Yorker website.

On the other hand, just doing a cursory search on the web found many glowing articles written by Yau about Chern.

Most recently: Yau, S.T. “Chern’s Work in Geometry”. Asian J. Math. 10, no 1. (2006), v-xii.

SS. Chern: A great geometer of the 20th century, Expanded Edition. 1998. Edited by S.T. Yau

Too bad Chern is not around to answer to this article, but it doesn’t seem like there’s been much conflict between the two.

]]>Remember the debate about “who should get credit for what?”. That is, of course, too subjective a topic and it invites madcap cretins. What Hamilton did in his letter was to depict precisely “who did what”, when the work was done, and how important it is to the completion of the Hamilton program, with all of the major players included. He left the question of “who should get credit for what?” to the readers, maybe even to the jury, if that proven to be necessary. For many, the question is now much easier to answer; for others, the answer may still be too hard to swallow, but that is irrelevant. Hamilton, although indirectly, gave his own answer to the question using mathematical and historical facts, and there is simply no one that is more qualified than he is to make the judgment. After all, everybody has been working in the Hamilton program. Did Yau need credit from Perelman for himself or for his students? Well, you can have your own answer.

What about the accusation that Yau did not think that Perelman deserves Fields medal? Hamilton’s confirmation of Yau’s support to Perelman answered that once for all. Anyone who is familiar with the Fields medal award process would know that he did not leave any room for doubt.

I love Hamilton’s mathematics. He has the talent to present his ideas in a simple, pure and beautiful way even when attacking some extremely difficult problems. His letter is written in almost the same fashion. The letter basically destroyed all the credibility of New Yorker’s “factual” attack to Yau.

If you read Perelman’s three papers and the other three expository papers (strictly speaking, there are only two such papers so far, Kleiner-Lott are still working on theirs), it is easy to find who has made what contribution to the proof of Poincare conjecture. All the relevant works, major and minor, have been cited. You can also find how much contribution was made by the other mathematicians (i.e. except Yau and Perelman) that were quoted by Nasar regarding Yau. Very little indeed. It makes you wonder why they should make any comments on Yau and Poincare conjecture at all. Some of them wanted credit for themselves, others for their students and the rest just want their fifteen minutes of fame.

Some people think Nasar is a good journalist, but allow me to disagree. Any experienced journalist would have his/her rear end covered when badmouthing one of the most important players in the story but without him on tape. Now, with the appearance of Hamilton’s letter, she gets herself exposed.

]]>Prof. Richard Hamilton, Columbia Univ., responds to the New Yorker article, September 25, 2006

http://doctoryau.com/hamiltonletter.pdf

Howard M Cooper

Todd & Weld LLP

28 State Street, Boston, MA 02109

Direct Dial (617) 624-4713 / Fax (617) 227-5777

hcooper@toddweld.com

September 25, 2006

Dear Mr. Cooper

I am very disturbed by the unfair manner in which Yau Shing-Tung has been portrayed in the New Yorker article. I am providing my thoughts below to set the record straight. I authorize you to share this letter with the New Yorker and the public if that will be helpful to Yau.

As soon as my first paper on the Ricci Flow on three dimensional manifolds with positive Ricci curvature was complete in the early ’80’s,Yau immediately recognized it’s importance;and although I had proved a result on which he had been working with minimal surfaces,rather than exhibit any jealosy he became my strongest supporter.He pointed out to me way back then that the Ricci Flow would form the neck pinch singularities,undoing the connected sum decomposition,and that this could lead to a proof of the Poincare conjecture. In 1985 he brought me to UC San Diego together with Rick Schoen and Gerhard Huisken,and we had a very exciting and productive group in Geometric Analysis.Huisken was working on the Mean Curvature Flow for hypersurfaces,which closely parallels the Ricci Flow,being the most natural flows for intrinsic and extrinsic curvature respectively.Yau repeatedly urged us to study the blow-up of singularities in these parabolic equations using techniques parallel to those developed for elliptic equations like the minimal surface equation,on which Yau and Rick are experts.Without Yau’s guidance and support at this early stage,there would have been no Ricci Flow program for Perelman to finish.

Yau also had some outstanding students at San Diego who had come with him from Princeton, in particular Cao Huai-Dong,Ben Chow and Shi Wan- Xiong. Yau encouraged them to work on the Ricci Flow,and all made very important contributions to the field.Cao proved existence for all time for the normalized Ricci Flow in the canonical Kaehler case ,and convergence for zero or negative Chern class.Cao’s results form the basis for Perelman’s exciting work on the Kaehler Ricci Flow,where he shows for positive Chern class that the diameter and scalar curvature are bounded. Ben Chow,in addition to excellent work on other flows,extended my work on the Ricci Flow on the two dimensional sphere to the case of curvature of varying sign.Shi Wan- Xiong pioneered the study of the Ricci Flow on complete noncompact manifolds,and in addition to many beautiful arguments he proved the local derivative estimates for the Ricci Flow.The blow-up of singularities usually produces noncompact solutions,and the proof of convergence to the blow-up limit always depends on Shi’s derivative estimates; so Shi’s work is central to all the limit arguments Perelman and I use.

In ’82 Yau and Peter Li wrote an exceedingly important paper giving a pointwise differential inequality for linear heat equations which can be integrated along curves to give classic Harnack inequalities. Yau repeatedly urged me to study this paper,and based on their approach I was able to prove Harnack inequalities for the Ricci Flow and for the Mean Curvature Flow. This Harnack inequality,generalized from Li-Yau,forms the basis for the analysis of ancient solutions which I started, and which Perelman completed and uses as the basic tool in his canonical neighborhood theorem. Cao Huai-Dong proved the Harnack estimate for the Ricci Flow in the Kahler case,and Ben Chow did the same for the Yamabe Flow and the Gauss Curvature Flow.

But there is more to this story. Perelman’s most important is his noncollapsing result for Ricci Flow,valid in all dimensions,not just three,and thus one whose importance for the future extends well beyond the Poincare conjecture,where it is the tool for ruling out cigars,the one part of the singularity classification I could not do. This result has two proofs,one using an entropy for a backward scalar heat equation,and one using a path integral.The entropy estimate comes from integrating a Li-Yau type differential Harnack inequality for the adjoint heat equation,and the other is the optimal Li-Yau path integral for the same Harnack inequality; as Perelman acknowledges in 7.4 of his first paper,where he writes “an even closer reference is [L-Y],where they use “length” associated to a linear parabolic equation,which is pretty much the same as in our case”.

Over the years Yau has consistently supported the Ricci Flow and the whole field of Geometric Flows,which has other important successes as well,such as the recent proof of the Penrose Conjecture by Huisken and Ilmanen,a very important result in General Relativity. I cannot think of any other prominent leader who gave nearly support to our field as Yau has.

Yau has built is an assembly of talent,not an empire of power,people attracted by his energy,his brilliant ideas,and his unflagging support for first rate mathematics, people whom Yau has brought together to work on the hardest problems.Yau and I have spent innumerable hours over many years working together on the Ricci Flow and other problems,often even late at night. He has always generously shared his suggestions with me,starting with the observation of neck pinches,never asking for credit. In fact just last winter when I finally managed to prove a local version of the Harnack inequality for the Ricci Flow,a problem we had worked on together for many years,and I said I ought to add his name to the paper,he modestly declined.It is unfortunate that his character has been so badly misrepresented.He has never to my knowledge proposed any percentages of credit,nor that Perelman should share credit for the Poincare conjecture with anyone but me; which is reasonable,as indeed no one has been more generous in crediting my work than Perelman himself.Far from stealing credit for Perelman’s accomplishment,he has praised Perelman’s work and joined me in supporting him for the Fields Medal.And indeed no one is more responsible than Yau for creating the program on Ricci Flow which Perelman used to win this prize.

Sincerely yours,

Richard S Hamilton

Professor of Mathematics,

Columbia University

Letter on Yau.nb 3