A new solution for a generalized cosmological wormhole
arXiv:2312.07736
Abstract
We find a new exact solution to Einstein field equations that represents a cosmological wormhole embedded in a flat Friedmann-Lemaître-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.
20 pages, accepted for publication in The European Physical Journal C