English

On Localization of Tight Closure in Line-$S_4$ Quartics

Commutative Algebra 2022-11-08 v1 Algebraic Geometry

Abstract

Building on work of Brenner and Monsky from 2010 and on a Hilbert-Kunz calculation of Monsky from 1998, we exhibit a novel example of a hypersurface over F2\overline{\mathbb{F}_2} in which tight closure does not commute with localization. Our methods involve a surprising tiling argument using Sierpi\'nski triangles, as well as an inspection of a certain dynamical system in characteristic two.

Keywords

Cite

@article{arxiv.2211.03220,
  title  = {On Localization of Tight Closure in Line-$S_4$ Quartics},
  author = {Levi Borevitz and Naima Nader and Theodore J. Sandstrom and Amelia Shapiro and Austyn Simpson and Jenna Zomback},
  journal= {arXiv preprint arXiv:2211.03220},
  year   = {2022}
}

Comments

Written during the 2022 SMALL REU at Williams College. Comments welcome