Torus equivariant cohomology theories from algebraic geometry

John Greenlees
Thursday, July 25, 2013 - from 11:00 to 12:00
There is a complete algebraic model A(G) for rational G-equivariant cohomology theories for a torus G. The category A(G) has a formal structure very similar to that of a category of sheaves over an algebraic variety, and this means that suitable algebraic geometric data lets one write down an object of A(G) representing a cohomology theory E^*_G(.). The most familiar example comes from a complex elliptic curve, giving rise to equivariant elliptic cohomology, but related constructions give other interesting examples. (Joint with Brooke Shipley and Pokman Cheung).