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arXiv · 1112.0802

Twisted Galois stratification

Ivan Tomasic
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Abstract

We prove a direct image theorem stating that the direct image of a Galois formula by a morphism of difference schemes is equivalent to a Galois formula over fields with powers of Frobenius. As a consequence, we obtain an effective quantifier elimination procedure and a precise algebraic-geometric description of definable sets over fields with Frobenii in terms of twisted Galois formulae associated with finite Galois covers of difference schemes.

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Ivan Tomasic. 2012-10-15. Twisted Galois stratification. https://arxiv.org/abs/1112.0802

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