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arXiv · 2104.13487

Covariant Isotropy of Grothendieck Toposes

Jason Parker
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Abstract

We provide an explicit characterization of the covariant isotropy group of any Grothendieck topos, i.e. the group of (extended) inner automorphisms of any sheaf over a small site. As a consequence, we obtain an explicit characterization of the centre of a Grothendieck topos, i.e. the automorphism group of its identity functor.

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Jason Parker. 2021-04-27. Covariant Isotropy of Grothendieck Toposes. https://arxiv.org/abs/2104.13487

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