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arXiv · 2512.20725

A remarkably simple covariant graviton propagator in Anti-de Sitter spacetime

Radu N. Moga·Kostas Skenderis
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Abstract

We present remarkably simple covariant expressions for the graviton and ghost propagators in Anti-de Sitter (AdS) spacetime valid in any spacetime dimension. In gravity there is a $2$-parameter family of covariant gauge-fixing conditions and the simplification occurs for a special choice of these parameters. In this gauge the graviton propagator satisfies $\nabla^\mu\mu\nabla^\nu\mu \, G_{\mu\nu,\alpha'\beta'}(\mu)=0$, where $\mu$ is the geodesic distance between two points, and this condition implies an improved infrared behavior. This gauge choice is not possible in flat spacetime.

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Radu N. Moga, Kostas Skenderis. 2025-12-23. A remarkably simple covariant graviton propagator in Anti-de Sitter spacetime. https://arxiv.org/abs/2512.20725

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