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arXiv · 1809.08209

On Rigidity of 3d Asymptotic Symmetry Algebras

A. Farahmand Parsa·H. R. Safari·M. M. Sheikh-Jabbari
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Abstract

We study rigidity and stability of infinite dimensional algebras which are not subject to the Hochschild-Serre factorization theorem. In particular, we consider algebras appearing as asymptotic symmetries of three dimensional spacetimes, the BMS3, u(1) Kac-Moody and Virasoro algebras. We construct and classify the family of algebras which appear as deformations of BMS3, u(1) Kac-Moody and their central extensions by direct computations and also by cohomological analysis. The Virasoro algebra appears as a specific member in this family of rigid algebras; for this case stabilization procedure is inverse of the Inönü-Wigner contraction relating Virasoro to BMS3 algebra. We comment on the physical meaning of deformation and stabilization of these algebras and relevance of the family of rigid algebras we obtain

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A. Farahmand Parsa, H. R. Safari, M. M. Sheikh-Jabbari. 2019-04-03. On Rigidity of 3d Asymptotic Symmetry Algebras. https://doi.org/10.1007/jhep03(2019)143

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