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arXiv · 1105.2426

Algebraic versus topological entropy for surfaces over finite fields

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

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Hélène Esnault, Vasudevan Srinivas. 2011-05-12. Algebraic versus topological entropy for surfaces over finite fields. https://arxiv.org/abs/1105.2426

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