Tropical curves, graph complexes, and the cohomology of M_g

Event time: 
Thursday, February 21, 2019 - 4:00pm
LOM 215
Melody Chan
Speaker affiliation: 
Brown University
Event description: 
The cohomology ring of the moduli space of curves of genus g is far

from being fully understood. For example, in the 1980s Harer-Zagier
showed that the Euler characteristic of M_g (up to sign) grows
super-exponentially with g—yet most of this cohomology is not
explicitly known. In joint work with Galatius and Payne, we identify a
new source of rational cohomology in M_g in degree 4g-6, with
dimension growing exponentially in g, disproving a vanishing
conjecture of Kontsevich.

Link to poster

Special note: 
Intersections Inaugural Seminar