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Contractions and generalized Casimir invariants

Rutwig Campoamor-Stursberg
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Abstract

We prove that if $\frak{g}^{\prime}$ is a contraction of a Lie algebra $\frak{g}$ then the number of functionally independent invariants of $\frak{g}^{\prime}$ is at least that of $\frak{g}$. This allows to determine explicitly the number of invariants of Lie algebras carrying a supplementary structure, such as linear contact or linear forms whose differential is symplectic.

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Rutwig Campoamor-Stursberg. 2002-04-26. Contractions and generalized Casimir invariants. https://arxiv.org/abs/math/0111185

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