An Isaac Newton Institute Programme

Model Theory and Applications to Algebra and Analysis

On the topological degree of functions definable in o-minimal structures

Authors: Yaacov Peterzil (University of Haifa), Sergei Starchenko (University of Notre Dame)

Abstract

We work in an o-minimal expansion of a real closed field. Using piecewise smoothness of definable functions we define the topological degree for definable continuous functions.

Using this notion of the degree we obtain a new proof for the existence of torsion points in a definably compact group.