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Extensions of Lie algebras

Dmitri Alekseevsky·Peter W. Michor·Wolfgang Ruppert
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Abstract

We review (non-abelian) extensions of a given Lie algebra, identify a 3-dimensional cohomological obstruction to the existence of extensions. A striking analogy to the setting of covariant exterior derivatives, curvature, and the Bianchi identity in differential geometry is spelled out. In the new version references added: Most of the results are known. So this paper will not be submitted to a journal, it can be regarded as a review paper.

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Dmitri Alekseevsky, Peter W. Michor, Wolfgang Ruppert. 2004-02-26. Extensions of Lie algebras. https://arxiv.org/abs/math/0005042

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