Date & Time: Wednesday, July 31, 2013, 15:30-16:30.
Venue: Ramanujan Hall
Title: Quadratic forms and Galois cohomology
Speaker: R. Parimala, Emory University
Abstract: Classical invariants of quadratic forms like the discriminant and the Clifford invariant take values in the Galois cohomology mod 2 of the field. Milnor conjecture, settled by Voevodsky, provides higher invariants for quadratic forms extending the classical invariants. We explain how bounded generation of Galois cohomology by symbols leads to the existence of non trivial zeros of quadratic forms in large enough number of variables.
The speaker will try to make the colloquium accessible to general audience.