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arXiv · 1208.1764

On Instability of Certain Bi-Metric and Massive-Gravity Theories

Florian Kuhnel
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Abstract

Stability about cosmological background solutions to the bi-metric Hassan-Rosen theory is studied. The results of this analysis are presented, and it is shown that a large class of cosmological backgrounds is classically unstable. This sets serious doubts on the physical viability of the Hassan-Rosen theory - and in turn also of the de Rham-Gadabaze-Tolley model, to which the mentioned theory is parent. A way to overcome this instability by means of curvature-type deformations is discussed.

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Florian Kuhnel. 2013-08-21. On Instability of Certain Bi-Metric and Massive-Gravity Theories. https://doi.org/10.1103/physrevd.88.064024

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