Intersections of $\omega$ classes in $\overline{\mathcal{M}}_{g,n}$

Vance Blankers; Renzo Cavalieri

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arXiv · 1705.10955

Intersections of $\omega$ classes in $\overline{\mathcal{M}}_{g,n}$

Vance Blankers·Renzo Cavalieri

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Abstract

We provide a graph formula which describes an arbitrary monomial in {\omega} classes (also referred to as stable {\psi} classes) in terms of a simple family of dual graphs (pinwheel graphs) with edges decorated by rational functions in {\psi} classes. We deduce some numerical consequences and in particular a combinatorial formula expressing top intersections of \k{appa} classes on Mg in terms of top intersections of {\psi} classes.

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Vance Blankers, Renzo Cavalieri. 2017-05-31. Intersections of $\omega$ classes in $\overline{\mathcal{M}}_{g,n}$. https://arxiv.org/abs/1705.10955

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