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arXiv · 1811.01072

Summands of theta divisors on Jacobians

Thomas Krämer
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Abstract

We show that the only summands of theta divisors on Jacobians of curves and on intermediate Jacobians of cubic threefolds are the obvious powers of the curve and the Fano surface of lines on the threefold. The proof uses the decomposition theorem for perverse sheaves, a bit of representation theory and a computation of characteristic cycles for Brill-Noether sheaves.

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Thomas Krämer. 2018-11-02. Summands of theta divisors on Jacobians. https://doi.org/10.1112/s0010437x20007204

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