Paper
FLRW embeddings in $\mathbb{R}^{n+2}$, differential geometry and conformal photon propagator
Authors
E. Huguet, J. Queva, J. Renaud
Abstract
This paper introduces differential-geometric methods to study -dimensional locally conformally flat spaces as submanifolds in . 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.