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arXiv · 1510.09208

Principal actions of stacky Lie groupoids

Henrique Bursztyn·Francesco Noseda·Chenchang Zhu
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Abstract

Stacky Lie groupoids are generalizations of Lie groupoids in which the "space of arrows" of the groupoid is a differentiable stack. In this paper, we consider actions of stacky Lie groupoids on differentiable stacks and their associated quotients. We provide a characterization of principal actions of stacky Lie groupoids, i.e., actions whose quotients are again differentiable stacks in such a way that the projection onto the quotient is a principal bundle. As an application, we extend the notion of Morita equivalence of Lie groupoids to the realm of stacky Lie groupoids, providing examples that naturally arise from non-integrable Lie algebroids.

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Henrique Bursztyn, Francesco Noseda, Chenchang Zhu. 2015-10-30. Principal actions of stacky Lie groupoids. https://arxiv.org/abs/1510.09208

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