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arXiv · 1804.05602

Linearization Instability of Chiral Gravity

Emel Altas·Bayram Tekin
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Abstract

Carrying out an analysis of the constraints and their linearizations on a spacelike hypersurface, we show that topologically massive gravity has a linearization instability at the chiral gravity limit about $AdS_3$. We also calculate the symplectic structure for all the known perturbative modes (including the log-mode) for the linearized field equations and find it to be degenerate (non-invertible) hence these modes do not approximate exact solutions and so do not belong to the linearized phase space of the theory. Naive perturbation theory fails: the linearized field equations are necessary but not sufficient in finding viable linearized solutions. This has important consequences for both classical and possible quantum versions of the theory.

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Emel Altas, Bayram Tekin. 2018-04-16. Linearization Instability of Chiral Gravity. https://doi.org/10.1103/physrevd.97.124068

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