English

Hurwitz Stacks of Groups Extensions and Irreducibility

Algebraic Geometry 2020-06-22 v2

Abstract

We study the irreducible components of special loci of curves whose group of symmetries is given as certain group extension. We introduce some relative Hurwitz data, which we show by using mixed \'etale cohomology theory, identifies some irreducible components for rational and normal non-abelian special loci and Hurwitz spaces. A heuristic, that is supported by three classes of examples, provides an additional context for building further irreducible loci.

Keywords

Cite

@article{arxiv.1803.06212,
  title  = {Hurwitz Stacks of Groups Extensions and Irreducibility},
  author = {Benjamin Collas and Sylvain Maugeais},
  journal= {arXiv preprint arXiv:1803.06212},
  year   = {2020}
}

Comments

Major update (27 pages): new irreducibility result and Heuristic (+2 sections,+ 1 figure, +7pages.)