Franecki and Kapranov proved that the Euler characteristic of a perverse sheaf on a semi-abelian variety is non-negative. This result has several purely topological consequences regarding the sign of the (topological and intersection homology) Euler characteristic of a subvariety of an abelian variety, and it is natural to attempt to justify them by more elementary methods. In this talk, we'll explore the geometric tools used in the proof of the signed Euler characteristic property. Joint work with Christian Geske and Laurentiu Maxim.
Speaker(s): Eva Elduque (University of Wisconsin)