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arXiv · 1009.0375

The Scorza correspondence in genus 3

Samuel Grushevsky·Riccardo Salvati Manni
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Abstract

In this note we prove the genus 3 case of a conjecture of G. Farkas and A. Verra on the limit of the Scorza correspondence for curves with a theta-null. Specifically, we show that the limit of the Scorza correspondence for a hyperelliptic genus 3 curve C is the union of the curve ${x,σ(x))$ (where $σ$ is the hyperelliptic involution), and twice the diagonal. Our proof uses the geometry of the subsystem Γ_{00} of the linear system 2Θ, and Riemann identities for theta constants.

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Samuel Grushevsky, Riccardo Salvati Manni. 2010-10-05. The Scorza correspondence in genus 3. https://arxiv.org/abs/1009.0375

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