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arXiv · 1605.05425

Powers of the theta divisor and relations in the tautological ring

Abstract

We show that the vanishing of the $(g+1)$-st power of the theta divisor in the cohomology and Chow rings of the universal abelian variety implies, by pulling back along a collection of Abel-Jacobi maps, the vanishing results in the tautological ring of $\mathcal{M}_{g,n}$ of Looijenga, Ionel, Graber-Vakil, and Faber-Pandharipande. We also show that Pixton's double ramification cycle relations, which generalize the theta vanishing relations and were recently proved by the first and third authors, imply Theorem $\star$ of Graber and Vakil. Moreover, our proof provides an algorithm for expressing any tautological class on $\overline{\mathcal{M}}_{g,n}$ of sufficiently high codimension as a tautological class supported on the boundary.

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Emily Clader, Samuel Grushevsky, Felix Janda, Dmitry Zakharov. 2022-12-25. Powers of the theta divisor and relations in the tautological ring. https://doi.org/10.1093/imrn%2Frnx115

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