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arXiv · 2210.11716

Cohomologies of difference Lie groups and van Est theorem

Jun Jiang·Yunnan Li·Yunhe Sheng
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Abstract

A difference Lie group is a Lie group equipped with a difference operator, equivalently a crossed homomorphism with respect to the adjoint action. In this paper, first we introduce the notion of a representation of a difference Lie group, and establish the relation between representations of difference Lie groups and representations of difference Lie algebras via differentiation and integration. Then we introduce a cohomology theory for difference Lie groups and justify it via the van Est theorem. Finally, we classify abelian extensions of difference Lie groups using the second cohomology group as applications.

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BibTeXRIS

Jun Jiang, Yunnan Li, Yunhe Sheng. 2022-10-21. Cohomologies of difference Lie groups and van Est theorem. https://arxiv.org/abs/2210.11716

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