Seminar in Real and Complex Geometry

Thursday, April 29, 2021, 16:00-17:30, online (via zoom)




Ilya Tyomkin
(Ben-Gurion University)

On (ir)reducibility of Severi varieties on toric surfaces


Abstract
             

In my talk I will discuss the problem of irreducibility of families of curves of given degree and genus on toric surfaces. Such families, called Severi varieties, have been intensively studied due to a variety of applications of their geometry to the study of moduli spaces of curves, and to various enumerative problems. After reviewing briefly known irreducibility results, I'll describe examples of toric surfaces admitting reducible Severi varieties, and introduce certain topological and tropical invariants that allow one to distinguish between different irreducible components. The talk is based on a joint work with Lionel Lang.