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About the group law for the Jacobi variety of a hyperelliptic curve

Frank Leitenberger
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Abstract

We generalize the group law of curves of degree three by chords and tangents to the Jacobi variety of a hyperelliptic curve. In the case of genus 2 we accomplish the construction by a cubic parabola. We derive explicit rational formulas for the addition on a dense set in the Jacobian.

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Frank Leitenberger. 2005-09-27. About the group law for the Jacobi variety of a hyperelliptic curve. https://arxiv.org/abs/math/0509638

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