Generation of Local Unitary Groups

Abstract

Let $E$ be a two-dimensional étale algebra over a non-Archimedean local field $K$ of characteristic zero. We show that the unitary group of a non-degenerate hermitian lattice over $E$ is generated by symmetries and rescaled Eichler isometries. In the appendix we show that unless $E/K$ is a ramified dyadic field extension and the residue field has two elements, symmetries suffice.

arXiv commentAppendix by Sven Manthe

References in corpus (1)

• Minimum positive entropy of complex Enriques surface automorphisms