A new proof of a theorem of Dutertre and Fukui on Morin singularities

Abstract

In [2], N.Dutertre and T. Fukui used Viro's integral calculus to study the topology of stable maps $f:M\to N$ between two smooth manifolds $M$ and $N$. They also discussed several applications to Morin maps. In particular, in Theorem 6.2 [2], they show an equality relating the Euler characteristic of a compact manifold $M$ and the Euler characteristic of the singular sets of a Morin map defined on $M$. In this paper we show how Morse theory for manifolds with boundary can be applied to the study of the singular sets of a Morin map in order to obtain a new proof of Dutertre-Fukui's Theorem when $N={\mathbb{R}}^n$.