Toward a Classification of Conformal Hypersurface Invariants

Samuel Blitz

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arXiv · 2212.11711

Toward a Classification of Conformal Hypersurface Invariants

Samuel Blitz

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Abstract

Hypersurfaces embedded in conformal manifolds appear frequently as boundary data in boundary-value problems in cosmology and string theory. Viewed as the non-null conformal infinity of a spacetime, we consider hypersurfaces embedded in a Riemannian (or Lorentzian) conformal manifold. We construct a finite and minimal family of hypersurface tensors -- the curvatures intrinsic to the hypersurface and the so-called ``conformal fundamental forms'' -- that can be used to construct natural conformal invariants of the hypersurface embedding up to a fixed order in hypersurface-orthogonal derivatives of the bulk metric. We thus show that these conformal fundamental forms capture the extrinsic embedding data of a conformal infinity in a spacetime.

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Samuel Blitz. 2022-12-22. Toward a Classification of Conformal Hypersurface Invariants. https://arxiv.org/abs/2212.11711

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