K3 surfaces with maximal finite automorphism groups containing M 20

Autor: Alessandra Sarti, Cédric Bonnafé
Přispěvatelé: Institut Montpelliérain Alexander Grothendieck (IMAG), Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Mathématiques et Applications (LMA-Poitiers), Université de Poitiers-Centre National de la Recherche Scientifique (CNRS), ANR-16-CE40-0010,GeRepMod,Méthodes géométriques en théorie des représentations modulaires des groupes réductifs finis(2016), ANR-18-CE40-0024,CATORE,CATEGORIFICATIONS EN TOPOLOGIE ET EN THEORIE DES REPRESENTATIONS(2018)
Rok vydání: 2021
Předmět:
Zdroj: Annales de l'Institut Fourier
Annales de l'Institut Fourier, Association des Annales de l'Institut Fourier, 2021, 71 (2), pp.711-730. ⟨10.5802/aif.3411⟩
ISSN: 1777-5310
0373-0956
DOI: 10.5802/aif.3411
Popis: It was shown by Mukai that the maximum order of a finite group acting faithfully and symplectically on a K3 surface is $960$ and that the group is isomorphic to the group $M\_{20}$. Then Kondo showed that the maximum order of a finite group acting faithfully on a K3 surface is $3\,840$ and this group contains the Mathieu group $M\_{20}$ with index four. Kondo also showed that there is a unique K3 surface on which this group acts faithfully, which is the Kummer surface $\Km(E\_i\times E\_i)$. In this paper we describe two more K3 surfaces admitting a big finite automorphism group of order $1\,920$, both groups contains $M\_{20}$ as a subgroup of index 2. We show moreover that these two groups and the two K3 surfaces are unique. This result was shown independently by S. Brandhorst and K. Hashimoto in a forthcoming paper, with the aim of classifying all the finite groups acting faithfully on K3 surfaces with maximal symplectic part.
15 pages
Databáze: OpenAIRE