Algebraic versus topological entropy for surfaces over finite fields
arXiv:1105.2426
Abstract
We show that, as in de Rham cohomology over the complex numbers, the value of the entropy of an automorphism of the surface over a finite field $\F_q $ is taken on the span of the Néron-Severi group inside of -adic cohomology. v2: (some) typos removed, exposition (partly) improved.
18 pages