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arXiv · 2504.21764

On the quotient of a groupoid by an action of a 2-group

Vladimir Drinfeld
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Abstract

If X is a groupoid equipped with an action of a 2-group G then one has a 2-groupoid X/G. We describe the fibers of the functor from X/G to the 1-groupoid $\pi_0(X)/\pi_0(G)$. We also give an explicit model for X/G in a certain situation.

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Vladimir Drinfeld. 2025-04-30. On the quotient of a groupoid by an action of a 2-group. https://arxiv.org/abs/2504.21764

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