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arXiv · 1808.04915

Classifying spaces and the Lascar group

Tim Campion·Greg Cousins·Jinhe Ye
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Abstract

We show that the Lascar group $\operatorname{Gal}_L(T)$ of a first order theory $T$ is naturally isomorphic to the fundamental group $π_1(|\operatorname{Mod}(T)|)$ of the classifying space of the category of models of $T$ and elementary embeddings.

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Tim Campion, Greg Cousins, Jinhe Ye. 2021-09-03. Classifying spaces and the Lascar group. https://doi.org/10.1017/jsl.2021.74

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