Numerical trivial automorphisms of Enriques surfaces in arbitrary characteristic

TL;DR

This paper generalizes existing results on automorphisms of complex Enriques surfaces to all characteristics, focusing on those automorphisms that act trivially on cohomology or its torsion part.

Contribution

It extends known results about trivial automorphisms of Enriques surfaces from complex to arbitrary characteristic fields.

Findings

Automorphisms acting trivially on cohomology are characterized in arbitrary characteristic.

Results unify the understanding of Enriques surface automorphisms across different characteristics.

The paper provides new tools for studying automorphisms in algebraic geometry.

Abstract

We extend to arbitrary characteristic some known results about automorphisms of complex Enriques surfaces that act trivially on the cohomology or the cohomology modulo torsion.