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arXiv · 1512.03587

The $p$-adic monodromy group of abelian varieties over global function fields of characteristic $p$

Ambrus Pal
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Abstract

We prove an analogue of the Tate isogeny conjecture and the semi-simplicity conjecture for overconvergent crystalline Dieudonn\'e modules of abelian varieties defined over global function fields of characteristic $p$. As a corollary we deduce that monodromy groups of such overconvergent crystalline Dieudonn\'e modules are reductive, and after a finite base change of coefficients their connected components are the same as the connected components of monodromy groups of Galois representations on the corresponding $l$-adic Tate modules, for $l$ different from $p$. We also show such a result for general compatible systems incorporating overconvergent $F$-isocrystals, conditional on a result of Abe.

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Ambrus Pal. 2015-12-11. The $p$-adic monodromy group of abelian varieties over global function fields of characteristic $p$. https://arxiv.org/abs/1512.03587

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