ON DEL PEZZO FIBRATIONS IN POSITIVE CHARACTERISTIC

Fabio Bernasconi, Hiromu Tanaka

2020Journal of the Institute of Mathematics of Jussieu31 citationsDOI Open Access PDF

Abstract

Abstract We establish two results on three-dimensional del Pezzo fibrations in positive characteristic. First, we give an explicit bound for torsion index of relatively torsion line bundles. Second, we show the existence of purely inseparable sections with explicit bounded degree. To prove these results, we study log del Pezzo surfaces defined over imperfect fields.

Topics & Concepts

MathematicsTorsion (gastropod)Pure mathematicsBounded functionImperfectMathematical analysisLinguisticsPhilosophyMedicineSurgeryAlgebraic Geometry and Number TheoryGeometry and complex manifoldsGeometric and Algebraic Topology