The Cohomological Excess of Certain Moduli Spaces of Curves of Genus $g$

Chitrabhanu Chaudhuri

The open subvariety ${\overline{M}}_g^{\le k}$ of ${\overline{M}}_g$ parametrizes stable curves of genus $g$ having at most $k$ rational components. By the work of Looijenga, one expe…