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arXiv · 2211.15291

On the tautological ring of Humbert curves

Robert Laterveer
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Abstract

We exhibit a 2-dimensional family of non-hyperelliptic curves of genus 5, called Humbert curves, for which the tautological ring injects into cohomology. In particular, Humbert curves have a multiplicative Chow-K\"unneth decomposition (in the sense of Shen-Vial), and their Ceresa cycle is torsion.

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Robert Laterveer. 2022-11-28. On the tautological ring of Humbert curves. https://doi.org/10.1007/s00229-022-01445-4

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