English

Extendable birational transformations belonging to Galois points

Algebraic Geometry 2023-02-03 v1

Abstract

We study birational transformations belonging to Galois points. Let PP be a Galois point for a plane curve CC and GPG_P be a Galois group at PP. Then an element of GPG_P induces a birational transformation of CC. In general, it is difficult to determine when this birational transformations can be extended to a Cremona (or projective) transformation. In this article, we shall prove that if the Galois group is isomorphic to the cyclic group of order three, then any element of the Galois group has an expression as a de Jonqui\`{e}res transformation. In particular, they can be extended to Cremona transformations.

Keywords

Cite

@article{arxiv.2302.00870,
  title  = {Extendable birational transformations belonging to Galois points},
  author = {Kei Miura},
  journal= {arXiv preprint arXiv:2302.00870},
  year   = {2023}
}

Comments

9 pages Comments are welcome. arXiv admin note: substantial text overlap with arXiv:1708.08195

R2 v1 2026-06-28T08:29:52.400Z