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arXiv · 1108.1922

Notes on Weak Units of Group-Like 1- and 2-Stacks

Ettore Aldrovandi·Ahmet Emin Tatar
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Abstract

The weak units of strict monoidal 1- and 2-categories are already defined. In this paper, we define them for group-like 1- and 2-stacks. We show that they form a contractible Picard 1- and 2-stack, respectively. We give their cohomological description which provides for these stacks a representation by complexes of sheaves of groups. Later, we extend the discussion to the monoidal case.

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Ettore Aldrovandi, Ahmet Emin Tatar. 2011-08-09. Notes on Weak Units of Group-Like 1- and 2-Stacks. https://arxiv.org/abs/1108.1922

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