Speaker: Dave Anderson
Title: Pfaffian formulas for symplectic degeneracy loci
Abstract:
Many interesting varieties arise as degeneracy loci: the set of points
where a map of vector bundles drops rank, or equivalently, the set of
points where two vector bundles intersect more than necessary. The
problem of finding formulas for the cohomology classes of these loci
dates to the 19th century, but has experienced a surge of interest in
the last few decades. The answer will be a universal polynomial in
the Chern classes of the vector bundles involved, and is closely
related to the equivariant classes of Schubert varieties in G/B, where
G is semisimple algebraic group. I'll describe recent progress in
understanding these polynomials in classical types, including joint
work with William Fulton.