On the Lie 2-algebra of sections of an LA-groupoid

Cristian Ortiz; James Waldron

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arXiv · 1703.09791

On the Lie 2-algebra of sections of an LA-groupoid

Cristian Ortiz·James Waldron

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Abstract

In this work we introduce the category of multiplicative sections of an $\la$-groupoid. We prove that this category carries natural strict Lie 2-algebra structures, which are Morita invariant. As applications, we study the algebraic structure underlying multiplicative vector fields on a Lie groupoid and in particular vector fields on differentiable stacks. We also introduce the notion of geometric vector field on the quotient stack of a Lie groupoid, showing that the space of such vector fields is a Lie algebra. We describe the Lie algebra of geometric vector fields in several cases, including classifying stacks, quotient stacks of regular Lie groupoids and in particular orbifolds, and foliation groupoids.

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Cristian Ortiz, James Waldron. 2017-03-28. On the Lie 2-algebra of sections of an LA-groupoid. https://arxiv.org/abs/1703.09791

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