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arXiv · 1502.03108

Characters of the BMS Group in Three Dimensions

Blagoje Oblak
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Abstract

Using the Frobenius formula, we evaluate characters associated with certain induced representations of the centrally extended BMS$_3$ group. This computation involves a functional integral over a coadjoint orbit of the Virasoro group; a delta function localizes the integral to a single point, allowing us to obtain an exact result. The latter is independent of the specific form of the functional measure, and holds for all values of the BMS$_3$ central charges and all values of the chosen mass and spin. It can also be recovered as a flat limit of Virasoro characters.

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Blagoje Oblak. 2015-06-10. Characters of the BMS Group in Three Dimensions. https://doi.org/10.1007/s00220-015-2408-7

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