English

Automorphisms of Generalized Fermat manifolds

Algebraic Geometry 2024-12-17 v8 Complex Variables

Abstract

Let d1d \geq 1, k2k \geq 2 and nd+1n\geq d+1 be integers. A dd-dimensional smooth complex algebraic variety MM is called a generalized Fermat variety of type (d;k,n)(d;k,n) if there is a Galois holomorphic branched covering π:MPd\pi:M \to {\mathbb P}^{d}, with deck group HZknH\cong {\mathbb Z}_{k}^{n}, whose branch divisor consists of n+1n+1 hyperplanes in general position, each one of branch order kk. In this case, HH is called a generalized Fermat group of type (d;k,n)(d;k,n). In previous work, we proved that the generalized Fermat group HH is unique in the following cases: (i) d=1d=1 and (k1)(n1)>2(k-1)(n-1)>2, or (ii) d2d \geq 2 and (d;k,n){(2;2,5),(2;4,3)}(d;k,n) \notin \{(2;2,5), (2;4,3)\}. To obtain this uniqueness fact, we used a differential method due to Kontogeorgis. This paper provides a different and shorter proof of the uniqueness of HH. We also study the locus of fixed points of subgroups of HH.

Keywords

Cite

@article{arxiv.2010.04628,
  title  = {Automorphisms of Generalized Fermat manifolds},
  author = {Ruben A. Hidalgo and Henry F. Hughes and Maximiliano Leyton-Alvarez},
  journal= {arXiv preprint arXiv:2010.04628},
  year   = {2024}
}

Comments

corrections from previous version and shorter version

R2 v1 2026-06-23T19:12:44.375Z