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arXiv · 1808.09518

The generalized Racah algebra as a commutant

Julien Gaboriaud·Luc Vinet·Stéphane Vinet·Alexei Zhedanov
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Abstract

The Racah algebra $R(n)$ of rank $(n-2)$ is obtained as the commutant of the \mbox{$\mathfrak{o}(2)^{\oplus n}$} subalgebra of $\mathfrak{o}(2n)$ in oscillator representations of the universal algebra of $\mathfrak{o}(2n)$. This result is shown to be related in a Howe duality context to the definition of $R(n)$ as the algebra of Casimir operators arising in recouplings of $n$ copies of $\mathfrak{su}(1,1)$. These observations provide a natural framework to carry out the derivation by dimensional reduction of the generic superintegrable model on the $(n-1)$ sphere which is invariant under $R(n)$.

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Julien Gaboriaud, Luc Vinet, Stéphane Vinet, Alexei Zhedanov. 2018-08-28. The generalized Racah algebra as a commutant. https://doi.org/10.1088/1742-6596%2F1194%2F1%2F012034

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