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arXiv · 0902.3531

On Unitarity of Massive Gravity in Three Dimensions

Masashi Nakasone·Ichiro Oda
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Abstract

We examine a unitarity of a particular higher-derivative extension of general relativity in three space-time dimensions, which has been recently shown to be equivalent to the Pauli-Fierz massive gravity at the linearized approximation level, and explore a possibility of generalizing the model to higher space-time dimensions. We find that the model in three dimensions is indeed unitary in the tree-level, but the corresponding model in higher dimensions is not so due to the appearance of non-unitary massless spin-2 modes.

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Masashi Nakasone, Ichiro Oda. 2009-04-06. On Unitarity of Massive Gravity in Three Dimensions. https://doi.org/10.1143/ptp.121.1389

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