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The group law for the Jacobi variety of plane curves

Frank Leitenberger
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Abstract

We extend the group law of curves of degree three by chords and tangents to the Jacobi variety of plane curves of degree n>4 by replacing points by point groups and lines by algebraic curves. The curves are nonsingular or have simple singularities. In the cases n=4,5,6 we have a close analogy to the case n=3. We describe an algorithm using Groebner bases.

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Frank Leitenberger. 2005-09-27. The group law for the Jacobi variety of plane curves. https://arxiv.org/abs/math/0509631

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