Speaker: Junliang Shen (MIT)
Join Zoom Meeting:
https://zoom.us/j/94787937855?pwd=c2FiS3VGaGowUGRpcTVoenJqZW8rQT09
Meeting ID: 947 8793 7855
Passcode: 323472
Time: 8h, Friday, January 8, 2021
Abstract: In general, the topology of the moduli space of semistable sheaves on an algebraic variety relies heavily on the choice of the Euler characteristic of the sheaves. We show a striking phenomenon that, for the moduli of 1-dimensional semistable sheaves on a toric del Pezzo surface (e.g. P^2) or the moduli of semistable Higgs bundles with respect to a divisor of degree > 2g-2 on a curve, the intersection cohomology (together with the perverse and the Hodge filtrations) of the moduli space is independent of the choice of the Euler characteristic.
This confirms a conjecture of Bousseau for P^2, and proves a conjecture of Toda in the case of certain local Calabi-Yau 3-folds. In the proof, a generalized version of Ngô's support theorem plays a crucial role. Based on joint with Davesh Maulik.
For general information of the AGEA seminar, please check out
https://sites.google.com/ncts.ntu.edu.tw/agea-seminar
or the mirror site
http://www.math.ntu.edu.tw/~jkchen/agea-seminar.html | 
