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arXiv · 1109.1894

Quadratic differential operators, Bicharacters and $\bullet$ Products

Iana I. Anguelova·Maarten J. Bergvelt
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Abstract

For a commutative cocommutative Hopf algebra we study the relationship between a certain linear map defined via a bicharacter, an exponential of a quadratic differential operator and a $\bullet$ product obtained via twisting by a bicharacter. This new relationship between $\bullet$ products and exponentials of quadratic differential operators was inspired by studying the exponential of a particular quadratic differential operator introduced by I. Frenkel, Lepowsky and Meurman in "Vertex operator algebras and the Monster", and used in the theory of twisted modules of lattice vertex algebras.

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Iana I. Anguelova, Maarten J. Bergvelt. 2011-09-09. Quadratic differential operators, Bicharacters and $\bullet$ Products. https://arxiv.org/abs/1109.1894

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