Virtual Hodge numbers of the moduli space of maps to projective space

Seminar: 
Geometry, Symmetry and Physics
Event time: 
Monday, February 16, 2026 - 4:30pm
Location: 
KT 801
Speaker: 
Siddarth Kannan
Speaker affiliation: 
MIT
Event description: 

I will discuss joint work with Terry Song on the calculation of the virtual Hodge numbers (i.e. Hodge—Deligne polynomial, Hodge-Euler characteristic, etc.) of the moduli space of degree-d maps to projective space from smooth n-pointed curves of genus g. Up to Brill—Noether loci in genus g>= 3, I will show how to reduce the calculation to the corresponding invariants of M_g,n. This reduction implies a strong stability statement for the virtual Hodge numbers as functions of the degree d, and suggests homological stability properties of the moduli space generalizing known statements in genus zero.  As an intermediate result, I will outline an analogous calculation for the universal Jacobian over M_g,n. As I will discuss, the theory of symmetric functions is fundamental to our approach.