||This biographical article needs additional citations for verification. (February 2013)|
Pierre Deligne, March 2005
3 October 1944 |
|Institutions||Institute for Advanced Study
Institut des Hautes Études Scientifiques
|Alma mater||Université libre de Bruxelles|
|Doctoral advisor||Alexander Grothendieck|
|Doctoral students||Lê Dũng Tráng
|Known for||Proof of the Weil conjectures|
|Notable awards||Abel Prize (2013)
Wolf Prize (2008)
Balzan Prize (2004)
Crafoord Prize (1988)
Fields Medal (1978)
Pierre René, Viscount Deligne (French: [dəliɲ]; born 3 October 1944) is a Belgian mathematician. He is known for work on the Weil conjectures, leading to a complete proof in 1973. He is the winner of the 2013 Abel Prize, 2008 Wolf Prize, and 1978 Fields Medal, making him one of four mathematicians to achieve this (along with John Milnor, Jean-Pierre Serre, and John G. Thompson).
After completing a doctorate under the supervision of Alexander Grothendieck, he worked with him at the Institut des Hautes Études Scientifiques (IHÉS) near Paris, initially on the generalization within scheme theory of Zariski's main theorem. In 1968, he also worked with Jean-Pierre Serre; their work led to important results on the l-adic representations attached to modular forms, and the conjectural functional equations of L-functions. Deligne's also focused on topics in Hodge theory. He introduced weights and tested them on objects in complex geometry. He also collaborated with David Mumford on a new description of the moduli spaces for curves. Their work came to be seen as an introduction to one form of the theory of algebraic stacks, and recently has been applied to questions arising from string theory. Perhaps Deligne's most famous contribution was his proof of the third and last of the Weil conjectures. This proof completed a programme initiated and largely developed by Alexander Grothendieck. As a corollary he proved the celebrated Ramanujan–Petersson conjecture for modular forms of weight greater than one; weight one was proved in his work with Serre. Deligne's paper (1974) contains the first proof of the Weil conjectures, Deligne's contribution being to supply the estimate of the eigenvalues of Frobenius, considered the geometric analogue of the Riemann hypothesis.
From 1970 until 1984, when he moved to the Institute for Advanced Study in Princeton, Deligne was a permanent member of the IHÉS staff. During this time he did much important work outside of his work on algebraic geometry. In joint work with George Lusztig, Deligne applied étale cohomology to construct representations of finite groups of Lie type; with Michael Rapoport, Deligne worked on the moduli spaces from the 'fine' arithmetic point of view, with application to modular forms. He received a Fields Medal in 1978.
In terms of the completion of some of the underlying Grothendieck program of research, he defined absolute Hodge cycles, as a surrogate for the missing and still largely conjectural theory of motives. This idea allows one to get around the lack of knowledge of the Hodge conjecture, for some applications. He reworked the tannakian category theory in his paper for the Grothendieck Festschrift, employing Beck's theorem – the Tannakian category concept being the categorical expression of the linearity of the theory of motives as the ultimate Weil cohomology. All this is part of the yoga of weights, uniting Hodge theory and the l-adic Galois representations. The Shimura variety theory is related, by the idea that such varieties should parametrize not just good (arithmetically interesting) families of Hodge structures, but actual motives. This theory is not yet a finished product – and more recent trends have used K-theory approaches.
- Deligne, Pierre (1974). "La conjecture de Weil: I". Publications Mathématiques de l'IHÉS 43: 273–307. doi:10.1007/bf02684373.
- Deligne, Pierre (1980). "La conjecture de Weil: II". Publications Mathématiques de l'IHÉS 52: 137–252. doi:10.1007/BF02684780.
- Deligne, Pierre; Mostow, G. Daniel (1993). Commensurabilities among Lattices in PU(1,n). Princeton, N.J.: Princeton University Press. ISBN 0-691-00096-4.
Deligne wrote multiple hand-written letters to other mathematicians in the 1970s. These include
- "Deligne’s letter to Piatetskii-Shapiro (1973)" (PDF). Retrieved 15 December 2012.
- "Deligne’s letter to Jean-Pierre Serre (around 1974)". 2012-12-15.
- "Deligne’s letter to Looijenga (1974)" (PDF). Retrieved 15 December 2012.
Concepts named after Deligne
The following mathematical concepts are named after Deligne:
- Deligne–Lusztig theory
- Deligne–Mumford moduli space of curves
- Deligne–Mumford stacks
- Deligne cohomology
- Fourier–Deligne transform
- Langlands–Deligne local constant
Additionally, many different conjectures in mathematics have been called the Deligne conjecture:
- The Deligne conjecture in deformation theory is about the operadic structure on Hochschild cohomology. It was proved by Kontsevich–Soibelman, McClure–Smith and others. It is of importance in relation with string theory.
- The Deligne conjecture on special values of L-functions is a formulation of the hope for algebraicity of L(n) where L is an L-function and n is an integer in some set depending on L.
- There is a Deligne conjecture on 1-motives arising in the theory of motives in algebraic geometry.
- There is a Gross–Deligne conjecture in the theory of complex multiplication.
- There is a Deligne conjecture on monodromy, also known as the weight monodromy conjecture, or purity conjecture for the monodromy filtration.
- There is Deligne conjecture in the representation theory of the exceptional Lie groups.
- There is a Deligne–Langlands conjecture of historical importance in relation with the development of the Langlands philosophy.
- Deligne's conjecture on the trace formula (now a theorem of Fujiwara).
- Official announcement ennoblement - Belgian Federal Public Service. 2006-07-18 Archived 30 October 2007 at the Wayback Machine
- Royal Swedish Academy of Sciences: Many new members elected to the Academy, press release on 12 February 2009[dead link]
- "Gruppe 1: Matematiske fag" (in Norwegian). Norwegian Academy of Science and Letters. Retrieved 26 April 2014.
|Wikinews has related news: Norwegian Academy of Science and Letters awards Belgian mathematician Pierre Deligne with Abel prize of 2013|
- O'Connor, John J.; Robertson, Edmund F., "Pierre Deligne", MacTutor History of Mathematics archive, University of St Andrews.
- Pierre Deligne at the Mathematics Genealogy Project
- Roberts, Siobhan (2012-06-19). "Simons Foundation: Pierre Deligne". Simons Foundation. — Biography and extended video interview.
- Pierre Deligne's home page at Institute for Advanced Study
- Katz, Nick (June 1980), "The Work Of Pierre Deligne", Proceedings of the International Congress of Mathematicians, Helsinki 1978 (PDF), Helsinki, pp. 47–52, ISBN 951-410-352-1 An introduction to his work at the time of his Fields medal award.