English

On the behavior of singularities at the $F$-pure threshold

Commutative Algebra 2019-06-25 v3 Algebraic Geometry

Abstract

We provide a family of examples where the FF-pure threshold and the log canonical threshold of a polynomial are different, but where pp does not divide the denominator of the FF-pure threshold (compare with an example of \mustata-Takagi-Watanabe). We then study the FF-signature function in the case where either the FF-pure threshold and log canonical threshold coincide or where pp does not divide the denominator of the FF-pure threshold. We show that the FF-signature function behaves similarly in those two cases. Finally, we include an appendix which shows that the test ideal can still behave in surprising ways even when the FF-pure threshold and log canonical threshold coincide.

Keywords

Cite

@article{arxiv.1508.05427,
  title  = {On the behavior of singularities at the $F$-pure threshold},
  author = {Eric Canton and Daniel Hernández and Karl Schwede and Emily Witt and Alessandro De Stefani and Jack Jeffries and Zhibek Kadyrsizova and Robert Walker and George Whelan},
  journal= {arXiv preprint arXiv:1508.05427},
  year   = {2019}
}

Comments

Typos corrected, other improvements to the exposition