Subtle Invariants of F-crystals

2013/11/16 by Xiao Xiao, Xiao, Xiao · 1 citation
Computer Science · Mathematics · #Algebraic Geometry and Number Theory #Coding theory and cryptography #FOS: Mathematics #Finite Group Theory Research #Number Theory (math.NT) #math.NT

paper · pdf · doi:10.48550/arxiv.1311.4009

Final accepted version at J. Ramanujan Math. Soc

openalex publication_date 2013/11/16 · arxiv created 2014/11/05 · arxiv updated 2014/11/06 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28

Abstract

Vasiu proved that the level torsion ℓ_M of an F-crystal M over an algebraically closed field of characteristic p>0 is a non-negative integer that is an effectively computable upper bound of the isomorphism number n_M of M and expected that in fact one always has n_M = ℓ_M. In this paper, we prove that this equality holds.

Cited by

• Minimal F-crystals and isomorphism numbers of isosimple F-crystals

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