Bounds for the number of Galois points for plane curves

Satoru Fukasawa

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arXiv · 1404.4413

Bounds for the number of Galois points for plane curves

Satoru Fukasawa

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Abstract

A point on a plane curve is said to be Galois (for the curve) if the projection from the point as a map from the curve to a line induces a Galois extension of function fields. It is known that the number of Galois points is finite except for a certain explicit example. We establish upper bounds for the number of Galois points for all plane curves other than the example in terms of the genus, degree and the generic order of contact, and settle curves attaining the bounds.

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Satoru Fukasawa. 2015-04-16. Bounds for the number of Galois points for plane curves. https://arxiv.org/abs/1404.4413

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