English

G-birationally rigid cubic threefolds

Algebraic Geometry 2026-04-23 v1

Abstract

We classify pairs (X,G)(X,G) consisting of a (possibly singular) cubic threefold XP4X\subset\mathbb{P}^4 and a finite subgroup GAut(X)G\subset\mathrm{Aut}(X) such that XX is GG-birationally rigid, i.e., XX is a GG-Mori fiber space (over a point), and XX is not GG-birational to any GG-Mori fibre space that is not GG-biregular to XX.

Keywords

Cite

@article{arxiv.2604.20426,
  title  = {G-birationally rigid cubic threefolds},
  author = {Ivan Cheltsov and Igor Krylov and Sione Ma'u},
  journal= {arXiv preprint arXiv:2604.20426},
  year   = {2026}
}

Comments

70 pages

R2 v1 2026-07-01T12:30:10.938Z