Highest weight representations of the Virasoro algebra
نویسنده
چکیده
We consider representations of the Virasoro algebra, a one-dimensional central extension of the Lie algebra of vectorfields on the unit circle. Positive-energy, highest weight and Verma representations are defined and investigated. The Shapovalov form is introduced, and we study Kac formula for its determinant and some consequences for unitarity and degeneracy of irreducible highest weight representations. In the last section we realize the centerless Ramond algebra as a super Lie algebra of superderivations.
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