A generalization of Voevodsky’s reconstruction theorem of schemes from their étale topoi
摘要
Let k be a field that is finitely generated over its prime field. In Grothendieck’s anabelian letter to Faltings, he conjectured that sending a k-scheme to its étale topos defines a fully faithful functor from the localization of the category of finite type k-schemes at the universal homeomorphisms to a category of topoi. By extending results of Voevodsky, we prove Grothendieck’s conjecture for infinite finitely generated fields of arbitrary characteristic. In characteristic 0, this shows that seminormal finite type k-schemes can be reconstructed from their étale topoi, generalizing work of Voevodsky. In positive characteristic, this shows that perfections of finite type k-schemes can be reconstructed from their étale topoi.