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arXiv · 2512.10901

FLRW embeddings in $\mathbb{R}^{n+2}$, differential geometry and conformal photon propagator

E. Huguet·J. Queva·J. Renaud
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Abstract

This paper introduces differential-geometric methods to study $n$-dimensional locally conformally flat spaces as submanifolds in $\mathbb{R}^{n+2}$. We derive explicit formulas relating intrinsic and ambient differential-geometric objects, including curvature tensors, the codifferential and laplacian operators. We apply this approach to Friedmann-Lemaître-Robertson-Walker (FLRW) spaces using newfound embedding formulas, obtaining new and simplified expressions for the photon propagator in four dimensions.

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E. Huguet, J. Queva, J. Renaud. 2026-03-24. FLRW embeddings in $\mathbb{R}^{n+2}$, differential geometry and conformal photon propagator. https://doi.org/10.1103/x3g4-b6s9

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