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arXiv · hep-th/9209090

Generalised Virasoro Constructions from Affine Inonu-Wigner Contractions

Stany Schrans
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Abstract

We present a new method to find solutions of the Virasoro master equations for any affine Lie algebra $\widehat{g}$. The basic idea is to consider first the simplified case of an Inönü-Wigner contraction $\widehat{g}_c$ of $\widehat{g}$ and to extend the Virasoro constructions of $\widehat{g}_c$ to $\widehat{g}$ by a perturbative expansion in the contraction parameter. The method is then applied to the orthogonal algebras, leading to fixed-level multi-parameter Virasoro constructions, which are the generalisations of the one-parameter Virasoro construction of $\widehat{su}(2)$ at level four.

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Stany Schrans. 1992-09-23. Generalised Virasoro Constructions from Affine Inonu-Wigner Contractions. https://doi.org/10.1088/0264-9381%2F10%2F9%2F011

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