2017/11/30 by Mitsui, Kentaro, Smeets, Arne
#14D06 #14G20 #14H10 #14H25 #Algebraic Geometry (math.AG) #FOS: Mathematics
paper · doi:10.48550/arxiv.1711.11547
Let K be the fraction field of a complete discrete valuation ring, with algebraically closed residue field of characteristic p > 0. This paper studies the index of a smooth, proper K-variety X with logarithmic good reduction. We prove that it is prime to p in `most' cases, for example if the Euler number of X does not vanish, but (perhaps surprisingly) not always. We also fully characterise curves of genus 1 with logarithmic good reduction, thereby completing classical results of T. Saito and Stix valid for curves of genus at least 2.