Department of Mathematics
Northeastern University

Geometry-Algebra-Singularities (GAS)

Meets Mondays 1:30-2:30 pm in 509 Lake Hall

Date:	Monday, September 22, 1997
Speaker:	Michael Farber (Tel Aviv University)
Title:	"Euler structures, Spinc-structures, and refined Reidemeister type torsion invariants of manifolds."
Talk:	1:30 PM in 509 Lake

Abstract:

In the talk I will describe:

1) The torsion invariant of Turaev depending on the choice

of an Euler structure, or a Spin^c-structure;

2) The other combinatorial torsion invariant computing the Ray-Singer

analytic torsion;

3) The relation between 1) and 2) involving characteristic classes.

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Date:	Monday, September 29, 1997
Speaker:	Mats Boij (Royal Institute of Technology, Stockholm)
Title:	"Betti number strata of the family of Gorenstein algebras in codimension three."
Talk:	1:30 PM in 509 Lake