English

Singularities in any Characteristic

Algebraic Geometry 2026-02-18 v2

Abstract

We give an overview of the fundamental definitions and results concerning hypersurface singularities, defined by convergent power series over an arbitrary real valued field. This approach combines, on the one hand, the classical case of analytic power series over the complex numbers with formal power series over arbitrary fields, but on the other hand, it goes significantly beyond that. Besides general definitions and basic results, we report on the classification of contact simple and right simple singularities in positive characteristic. Some of the results are new in this general setting, for which we provide complete proofs.

Keywords

Cite

@article{arxiv.2602.02042,
  title  = {Singularities in any Characteristic},
  author = {Gert-Martin Greuel},
  journal= {arXiv preprint arXiv:2602.02042},
  year   = {2026}
}

Comments

41 pages. In Memoriam Wolfgang Ebeling. Titel changed. Accepted for publication in the Journal of Singularities, Special volume in honor of Wolfgang Ebeling

R2 v1 2026-07-01T09:31:44.658Z