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arXiv · hep-th/9509088

Non-Polynomial Realizations of W-Algebras

F. Barbarin·E. Ragoucy·P. Sorba
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Abstract

Relaxing first-class constraint conditions in the usual Drinfeld-Sokolov Hamiltonian reduction leads, after symmetry fixing, to realizations of W algebras expressed in terms of all the J-current components. General results are given for G a non exceptional simple (finite and affine) algebra. Such calculations directly provide the commutant, in the (closure of) G enveloping algebra, of the nilpotent subalgebra $G_-$, where the subscript refers to the chosen gradation in G. In the affine case, explicit expressions are presented for the Virasoro, $W_3$, and Bershadsky algebras at the quantum level.

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F. Barbarin, E. Ragoucy, P. Sorba. 1995-09-18. Non-Polynomial Realizations of W-Algebras. https://doi.org/10.1142/s0217751x96001383

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