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arXiv · 2401.02346

An Elementary Approach to the Group Law on Elliptic Curves

Sander Zwegers
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Abstract

We revisit the group structure on elliptic curves and give a simple and elementary proof of the associativity of the addition. We do this by providing an explicit formula for the sum of three points, only using the explicit definition of the group structure. In the process we find a nice geometric interpretation of the sum of three points on the elliptic curve.

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Sander Zwegers. 2024-01-04. An Elementary Approach to the Group Law on Elliptic Curves. https://arxiv.org/abs/2401.02346

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