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arXiv · 1510.08880

Quotients of hyperelliptic curves and etale cohomology

Tim Dokchitser·Vladimir Dokchitser
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Abstract

We study hyperelliptic curves C with an action of an affine group of automorphisms G. We establish a closed form expression for the quotient curve C/G and for the first etale cohomology group of C as a representation of G. The motivation comes from the arithmetic of hyperelliptic curves over local fields, specifically their local Galois representations and the associated invariants.

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Tim Dokchitser, Vladimir Dokchitser. 2016-05-10. Quotients of hyperelliptic curves and etale cohomology. https://doi.org/10.1093/qmath%2Fhax053

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