Yesterday I went down to the Institute in Princeton with my friend Oisin McGuinness to attend one day of a conference in honor of Pierre Deligne that is going on there this week. Deligne has spent most of his career at the IHES and at the Institute, and this conference was in honor of his 61st birthday (I suspect they initially planned it for last year, but it got pushed back).

Deligne worked with Grothendieck at the IHES during the late sixties, and is perhaps best known for his proof of the Weil conjectures completed in 1974, an achievement which won him a Fields medal in 1978. The Weil conjectures motivated much of the work by Grothendieck and others in algebraic geometry during the fifties and sixties, and Deligne was able to finish a proof using Grothendieck’s machinery as well as some different ideas of his own. For more about Grothendieck, visit the Grothendieck Circle web-site. Grothendieck left the IHES around 1970, and later became a recluse, increasingly hostile towards his former colleagues, especially Deligne, who he attacked in his long unpublished manuscript “Recoltes et Semailles.” Several people told me that at the conference banquet held Tuesday night, after an array of different speakers rose to praise Deligne, especially for his generosity with his ideas and help to others, Deligne himself spoke and said that he was only repaying the debt he owed to Grothendieck, who himself was famous for such generosity.

One of the conference talks I heard was by Gerard Laumon, who described some of his work with Ngo Bau Chau on the Fundamental Lemma. Various lecture notes on this subject are available here. Laumon emphasized the role of equivariant cohomology in the proof, a method pioneered by Goresky, Kottwitz and MacPherson. Equivariant cohomology techniques are also crucially behind much work on topological quantum field theory, although of course the context is quite different there.

“Several people told me that at the conference banquet held Tuesday night, after an array of different speakers rose to praise Deligne, especially for his generosity with his ideas and help to others, Deligne himself spoke and said that he was only repaying the debt he owed to Grothendieck, who himself was famous for such generosity.”

Wow. That is very touching.

Thanks for reporting and for the lecture notes. Do you know by any chance if they made some videos of the talks ?

Grothendieck was very generous with his ideas (and 1000’s of pages of published manuscripts) up to his breakdown in the late 60’s and break up with the mathematical community. Things changed after that point, as he became increasingly bitter, and started accusing people of stealing his ideas and/or not giving him credit. Some of the things he said in his latter (autobiographical)writings were mean and paranoid.

Hi there,

I am an undergraduate physics student in New Zealand.

I’m not sure if this is right place to post this but I was wondering if you ‘expert’ physicists could have a look around my weblog and if there are misunderstandings in the articles that I write, to correct me. I’m only a junior in University so I have a lot more to learn and I think your comments or criticism of feedback will help me learn A LOT more. Thanks!

http://precondition.blogspot.com

criticism of feeback ==> criticism or feedback

typo sorry : D

Actually, the 61st birthday was celebrated as opposed to the 60th because Pierre likes prime numbers..

Geon Oh,

I tried to comment on your blog. but it is restricted to team members.

Hi Wolfgang

Thanks for your comment

I corrected the setting so that anyone can make comments.

I appreciate your interest in my ‘newbie’ weblog.

Thanks!

http://precondition.blogspot.com