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arXiv · 2311.08985

Post-Lie algebra structures for perfect Lie algebras

Dietrich Burde·Karel Dekimpe·Mina Monadjem
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Abstract

We study the existence of post-Lie algebra structures on pairs of Lie algebras $(\mathfrak{g},\mathfrak{n})$, where one of the algebras is perfect non-semisimple, and the other one is abelian, nilpotent non-abelian, solvable non-nilpotent, simple, semisimple non-simple, reductive non-semisimple or complete non-perfect. We prove several non-existence results, but also provide examples in some cases for the existence of a post-Lie algebra structure. Among other results we show that there is no post-Lie algebra structure on $(\mathfrak{g},\mathfrak{n})$, where $\mathfrak{g}$ is perfect non-semisimple, and $\mathfrak{n}$ is $\mathfrak{sl}_3(\mathbb{C})$. We also show that there is no post-Lie algebra structure on $(\mathfrak{g},\mathfrak{n})$, where $\mathfrak{g}$ is perfect and $\mathfrak{n}$ is reductive with a $1$-dimensional center.

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Dietrich Burde, Karel Dekimpe, Mina Monadjem. 2023-11-15. Post-Lie algebra structures for perfect Lie algebras. https://arxiv.org/abs/2311.08985

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