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arXiv · hep-th/9301040

Folding the W Algebras

L. Frappat·E. Ragoucy·P. Sorba
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Abstract

In the same way the folding of the Dynkin diagram of A_{2n} (resp. A_{2n-1}) produces the B_n (resp. C_n) Dynkin diagram, the symmetry algebra W of a Toda model based on B_n (resp. C_n) can be seen as resulting from the folding of a W-algebra based on A_{2n} (resp. A_{2n-1}). More generally, W algebras related to the B-C-D algebra series can appear from W algebras related to the unitary ones. Such an approach is in particular well adapted to obtain fusion rules of W algebras based on non simply laced algebras from fusion rules corresponding to the A_n case. Anagously, super W algebras associated to orthosymplectic superalgebras are deduced from those relative to the unitary A(m,n) series.

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L. Frappat, E. Ragoucy, P. Sorba. 1993-01-12. Folding the W Algebras. https://doi.org/10.1016/0550-3213(93)90598-j

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