**Date & Time:** January 16, 2013; 16:00-17:00.

**Venue:** Ramanujan Hall

**Title : **Euler class groups and Chow-Witt groups

**Speaker:** Prof. Sarang Sane

**Abstract:** Projective modules are algebraic analogues of vector bundles and the question of finding a free direct summand of such modules is analogous to the question of nowhere vanishing sections (think of nonzero vector fields) of bundles. In the past decade and half, two theories (as in the title) have been developed to provide obstruction classes for splitting of projective modules, analogous to singular cohomology which does the same for bundles. We will survey the origins, both the theories and time permitting, consider connections between them.