Texas A&M University, Department of Mathematics, 216 Milner Hall, 17th of November 2004, 3:00-3:50

Groups and Dynamics Seminar


Reidemeister torsion and dynamical zeta functions

Alexander Fel'shtyn of Universität Siegen

Reidemeister torsion is a very important topological invariant which has useful applications in the theory of  manifolds and  knots, theory of elliptic operators and quantum field theory. Recently, the Reidemeister torsion has found interesting applications in dynamical systems theory.  A connection between the Weil type dynamical zeta functions and the Reidemeister torsion was established
by Milnor and Fried . In the talk we discuss a connection between the Reidemeister torsion and Reidemeister zeta function of a group automorphism. The result is obtained by expressing the Reidemeister zeta function in terms of the Weil zeta function of the unitary dual map, and then applying the theorem of Milnor and Fried. What this means is that the Reidemeister torsion counts the twisted conjugacy classes of all iterates of a group automorphism and fixed point classes of all iterates of a map, i.e. periodic point classes of a map.