Cohomologie \'etale des espaces d'arcs

Alexis Bouthier

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arXiv · 1509.02203

Cohomologie \'etale des espaces d'arcs

Alexis Bouthier

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Abstract

We establish a structure theorem on the arc space of a $k$-scheme of finite type. More precisely, we show that the arc space is locally for the pro-smooth toplogy a product of an infinite dimensional affine space and of a non-noetherian scheme, stratified by $k$-schemes of finite type, that glues the different formal completions of the arc space. This statement globalizes Drinfeld-Grinberg-Kazhdan's theorem and proves a conjecture of Kollar and Nemethi. Then, we use this theorem to construct a derived category of constructible sheaves, stable by six operations and we show a finiteness result for the cohomology.

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BibTeX RIS

Alexis Bouthier. 2015-09-07. Cohomologie \'etale des espaces d'arcs. https://arxiv.org/abs/1509.02203

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