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arXiv · 2312.07736

A new solution for a generalized cosmological wormhole

Daniela Pérez·Mário Raia Neto
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Abstract

We find a new exact solution to Einstein field equations that represents a cosmological wormhole embedded in a flat Friedmann-Lema\^itre-Robertson-Walker universe. The new metric is a generalization of a previous cosmological wormhole solution found by Kim. We explicitly show that the flaring out condition is satisfied at the throat at all cosmic times; in addition, the null energy condition is violated at the throat regardless of the background cosmological model; thus, the spacetime geometry presented here describes a wormhole coupled to the cosmic dynamics that exists at all cosmic times and whose throat remains open in any cosmological model.

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Daniela Pérez, Mário Raia Neto. 2023-12-12. A new solution for a generalized cosmological wormhole. https://arxiv.org/abs/2312.07736

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