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arXiv · 1502.06253

Modular Classes of Lie Groupoid Representations up to Homotopy

Rajan Amit Mehta
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Abstract

We describe a construction of the modular class associated to a representation up to homotopy of a Lie groupoid. In the case of the adjoint representation up to homotopy, this class is the obstruction to the existence of a volume form, in the sense of Weinstein's "The volume of a differentiable stack".

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Rajan Amit Mehta. 2015-02-22. Modular Classes of Lie Groupoid Representations up to Homotopy. https://doi.org/10.3842/sigma.2015.058

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