Abstract : I will present results about Dirac operators on stratified pseudomanifolds.
I will concentrate mainly on the signature operator on an orientable stratified
pseudomanifolds, for example a singular projective variety, but I will also touch briefly
the case of the spin-Dirac operator on a spin-pseudomanifold. I will first focus on giving
a survey of the main theorems concerning the Fredholm index, and more generally
the K-homology class, associated to a Dirac operator satisfying the so-called Witt assumption, with
particular emphasis on the two examples I have already mentioned. I will then move to recent results
in collaboration with Pierre Albin and Markus Banagl. I will explain how to define, analytically,
wrong-way maps in K-homology in this stratified context
and how they are related to existing wrong-way maps in topology.
I will then end my talk by illustrating a fundamental property of these
wrong-way maps, namely that they preserve the signature K-homology class.