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COLUMBIA UNIVERSITY

DEPARTMENT OF MATHEMATICS

JOSEPH FELS RITT LECTURES

David Vogan

Massachusetts Institute of Technology

**Geometry and Representations of Reductive
Groups
Abstract: The Kirillov-Kostant "orbit
philosophy" says that unitary irreducible representations of Lie groups should
correspond
(by "quantization") to symplectic homogeneous spaces. Symplectic homogeneous
spaces are very easy to understand, but "quantization"
remains mysterious. I'll talk about some of the things that we do understand,
and about ways to approach the problems that remain.
The most important geometry that appears is the geometry of conjugacy classes
of nilpotent matrices.**

**
Thursday, December 13
312 Mathematics Building
4:00 p.m.
Friday, December 14
203 Mathematics Building
4:00 p.m.
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Tea will be served at 3:15 p.m. both days
508 Mathematics
Building
Directions to Columbia University**