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arXiv · 1703.09050

A Generalized Blakers-Massey Theorem

Mathieu Anel·Georg Biedermann·Eric Finster·André Joyal
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Abstract

We prove a generalization of the classical connectivity theorem of Blakers-Massey, valid in an arbitrary higher topos and with respect to an arbitrary modality, that is, a factorization system (L,R) in which the left class is stable by base change. We explain how to rederive the classical result, as well as a recent generalization by Chach\'olski-Scherer-Werndli. Our proof is inspired by the one given in Homotopy Type Theory.

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Mathieu Anel, Georg Biedermann, Eric Finster, André Joyal. 2017-03-27. A Generalized Blakers-Massey Theorem. https://doi.org/10.1112/topo.12163

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