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arXiv · 2012.08447

Connections on Lie groupoids and Chern-Weil theory

Indranil Biswas·Saikat Chatterjee·Praphulla Koushik·Frank Neumann
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Abstract

Let $\mathbb{X}=[X_1\rightrightarrows X_0]$ be a Lie groupoid equipped with a connection, given by a smooth distribution $\mathcal{H} \subset T X_1$ transversal to the fibers of the source map. Under the assumption that the distribution $\mathcal{H}$is integrable, we define a version of de Rham cohomology for the pair $(\mathbb{X}, \mathcal{H})$, and we study connections on principal $G$-bundles over $(\mathbb{X}, \mathcal{H})$ in terms of the associated Atiyah sequence of vector bundles. We also discuss associated constructions for differentiable stacks. Finally, we develop the corresponding Chern-Weil theory and describe characteristic classes of principal G-bundles over a pair $(\mathbb{X}, \mathcal{H})$.

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Indranil Biswas, Saikat Chatterjee, Praphulla Koushik, Frank Neumann. 2020-12-15. Connections on Lie groupoids and Chern-Weil theory. https://arxiv.org/abs/2012.08447

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