English

Rings of tautological forms on moduli spaces of curves

Algebraic Geometry 2023-05-24 v2 Differential Geometry

Abstract

We define and study a natural system of tautological rings on the moduli spaces of marked curves at the level of differential forms. We show that certain 2-forms obtained from the natural normal functions on these moduli spaces are tautological. Also we show that rings of tautological forms are always finite dimensional. Finally we characterize the Kawazumi-Zhang invariant as essentially the only smooth function on the moduli space of curves whose Levi form is a tautological form.

Keywords

Cite

@article{arxiv.2207.05428,
  title  = {Rings of tautological forms on moduli spaces of curves},
  author = {Robin de Jong and Stefan van der Lugt},
  journal= {arXiv preprint arXiv:2207.05428},
  year   = {2023}
}

Comments

32 pages; v2: incorporated referee's remarks