“The modular character
ring and its associated
monomial Burnside ring, part II”
Abstract: When the scalar field is algebraically closed, Boltje's canonical induction formula provides a canonical way of lifting characters to elements of the monomial Burnside ring. A crucial component of the theory is an integrality property, a guarantee that the formula is a map of integral lattices, not just a map of vector space extensions of the lattices. We shall discuss Symonds' proof of integrality which, in characteristic zero, realizes the Boltje lifting as a kind of monomial Lefschetz invariant of the projective fibre-bundle associated with the module. We shall explain how his proof also applies to the modular scenario.
Date : October 5, 2009 (Monday)
Place: Seminar Room SA-141