# Algebraic versus topological entropy for surfaces over finite fields

Hélène Esnault, Vasudevan Srinivas

Number | 15 |
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Author | Hélène Esnault |

Year | 2011 |

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 N\'eron-Severi group inside of $\ell$-adic cohomology. v2: (some) typos removed, exposition (partly) improved.