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arXiv · 2508.13852

Codimension two spacelike submanifolds into null hypersurfaces of generalized Robertson-Walker spacetimes

Luis J. Alias·Josue Melendez·Matias Navarro·Didier A. Solis
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Abstract

We study codimension two spacelike submanifolds contained into a general class of null hypersurfaces in generalized Robertson-Walker spacetimes, refer to as nullcones. In particular we analyze light cones and lightlike cylinders in Lorentz-Minkowski spacetime, as well as null cones in de Sitter spacetime. We give conditions on a radial coordinate that guarantee that such a spacelike submanifold is conformally diffeomorphic to the hyperbolic space, a round cylinder a sphere; respectively. We also provide some non-existence results for weakly trapped submanifolds.

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Luis J. Alias, Josue Melendez, Matias Navarro, Didier A. Solis. 2025-08-19. Codimension two spacelike submanifolds into null hypersurfaces of generalized Robertson-Walker spacetimes. https://arxiv.org/abs/2508.13852

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