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arXiv · 0912.0557

Quasi root systems and vertex operator realizations of the Virasoro algebra

Boris Noyvert
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Abstract

A construction of the Virasoro algebra in terms of free massless two-dimensional boson fields is studied. The ansatz for the Virasoro field contains the most general unitary scaling dimension 2 expression built from vertex operators. The ansatz leads in a natural way to a concept of a quasi root system. This is a new notion generalizing the notion of a root system in the theory of Lie algebras. We introduce a definition of a quasi root system and provide an extensive list of examples. Explicit solutions of the ansatz are presented for a range of quasi root systems.

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Boris Noyvert. 2009-12-03. Quasi root systems and vertex operator realizations of the Virasoro algebra. https://doi.org/10.1142/s021949881350028x

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