Generalization of a conjecture of Mumford

Autor: Dan, Ananyo, Kaur, Inder
Rok vydání: 2019
Předmět:
Druh dokumentu: Working Paper
DOI: 10.1016/j.aim.2021.107676
Popis: A conjecture of Mumford predicts a complete set of relations between the generators of the cohomology ring of the moduli space of rank 2 semi-stable sheaves with fixed odd degree determinant on a smooth, projective curve of genus at least 2. The conjecture was proven by Kirwan. In this article, we generalize the conjecture to the case when the underlying curve is irreducible, nodal. In fact, we show that these relations (in the nodal curve case) arise naturally as degeneration of the Mumford relations shown by Kirwan in the smooth curve case. As a byproduct, we compute the Hodge-Poincare polynomial of the moduli space of rank 2, semi-stable, torsion-free sheaves with fixed determinant on an irreducible, nodal curve.
Comment: Very minor changes, as suggested by the referee. To appear in Advances in Mathematics
Databáze: arXiv