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arXiv · 2303.15744

Cohomology and deformations of crossed homomorphisms between Lie-Yamaguti algebras

Jia Zhao·Yu Qiao·Senrong Xu
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Abstract

In this paper, we introduce the notion of crossed homomorphisms between Lie-Yamaguti algebras and establish the cohomology theory of crossed homomorphisms via the Yamaguti cohomology. Consequently, we use this cohomology to characterize linear deformations of crossed homomorphisms between Lie-Yamaguti algebras. We show that if two linear or formal deformations of a crossed homomorphism are equivalent, then their infinitesimals are in the same cohomology class in the first cohomology group. Moreover, we show that an order $n$ deformation of a crossed homomorphism can be extended to an order $n+1$ deformation if and only if the obstruction class in the second cohomology group is trivial.

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Jia Zhao, Yu Qiao, Senrong Xu. 2023-03-28. Cohomology and deformations of crossed homomorphisms between Lie-Yamaguti algebras. https://arxiv.org/abs/2303.15744

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