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Compilation of relations for the antisymmetric tensors defined by the Lie algebra cocycles of $su(n)$

J. A. de Azcárraga·A. J. Macfarlane
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Abstract

This paper attempts to provide a comprehensive compilation of results, many new here, involving the invariant totally antisymmetric tensors (Omega tensors) which define the Lie algebra cohomology cocycles of $su(n)$, and that play an essential role in the optimal definition of Racah-Casimir operators of $su(n)$. Since the Omega tensors occur naturally within the algebra of totally antisymmetrised products of $λ$-matrices of $su(n)$, relations within this algebra are studied in detail, and then employed to provide a powerful means of deriving important Omega tensor/cocycle identities. The results include formulas for the squares of all the Omega tensors of $su(n)$. Various key derivations are given to illustrate the methods employed.

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J. A. de Azcárraga, A. J. Macfarlane. 2001-05-17. Compilation of relations for the antisymmetric tensors defined by the Lie algebra cocycles of $su(n)$. https://doi.org/10.1142/s0217751x01003111

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