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Integrating Lie algebroids via stacks

Hsian-Hua Tseng·Chenchang Zhu
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Abstract

Lie algebroids can not always be integrated into Lie groupoids. We introduce a new object--``Weinstein groupoid'', which is a differentiable stack with groupoid-like axioms. With it, we have solved the integration problem of Lie algebroids. It turns out that every Weinstein groupoid has a Lie algebroid and every Lie algebroid can be integrated into a Weinstein groupoid.

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Hsian-Hua Tseng, Chenchang Zhu. 2006-11-27. Integrating Lie algebroids via stacks. https://arxiv.org/abs/math/0405003

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