LOWER BOUNDS ON THE F-PURE THRESHOLD AND EXTREMAL SINGULARITIES


Kadyrsizova Z. Kenkel J. Page J. Singh J. Smith K.E. Vraciu A. Witt E.E.
2022American Mathematical Society

Transactions of the American Mathematical Society Series B
2022#9Issue 31977 - 1005 pp.

We prove that if f is a reduced homogeneous polynomial of degree d, then its F-pure threshold at the unique homogeneous maximal ideal is at 1 least d−1. We show, furthermore, that itsF-pure threshold equals 1 if and d−1 only if f ∈ m[q] and d = q +1, where q is a power of p. Up to linear changes of coordinates (over a fixed algebraically closed field), we classify such “extremal singularities”, and show that there is at most one with isolated singularity. Finally, we indicate several ways in which the projective hypersurfaces defined by such forms are “extremal”, for example, in terms of the configurations of lines they can contain.



Text of the article Перейти на текст статьи

Nazarbayev University, Nur-Sultan, Kazakhstan
Department of Mathematics, University of Michigan, Ann Arbor, 48109, MI, United States
Department of Mathematics, North Dakota State University, Fargo, 58105, ND, United States
Department of Mathematics, Visvesvaraya National Institute of Technology, Nagpur, India
Department of Mathematics, University of South Carolina, Columbia, 29208, SC, United States
Department of Mathematics, University of Kansas, Lawrence, 66045, KS, United States

Nazarbayev University
Department of Mathematics
Department of Mathematics
Department of Mathematics
Department of Mathematics
Department of Mathematics

10 лет помогаем публиковать статьи Международный издатель

Книга Публикация научной статьи Волощук 2026 Book Publication of a scientific article 2026