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arXiv · 1811.07676

`Hidden' symmetry of linearized gravity in de Sitter space

Hamed Pejhan·Surena Rahbardehghan·Mohammad Enayati·Kazuharu Bamba·Anzhong Wang
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Abstract

We demonstrate that the linearized Einstein gravity in de Sitter (dS) spacetime besides the evident symmetries also possesses the additional (local) symmetry $h_{\mu\nu}\rightarrow h_{\mu\nu} + {\cal E}_{\mu\nu}\chi$, where ${\cal E}_{\mu\nu}$ is a spin-two projector tensor and $\chi$ is an arbitrary constant function. We argue that an anomalous symmetry associated with this hitherto `hidden' property of the existing physics is indeed at the origin of `dS breaking' in linearized quantum gravity.

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Hamed Pejhan, Surena Rahbardehghan, Mohammad Enayati, Kazuharu Bamba, Anzhong Wang. 2018-11-19. `Hidden' symmetry of linearized gravity in de Sitter space. https://doi.org/10.1016/j.physletb.2019.06.012

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