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4D Wormhole with Signature Change in the Presence of Extra Dimensions

V. Dzhunushaliev·H. -J. Schmidt
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Abstract

A regular vacuum solution in 5D gravity on the principal bundle with the U(1) structural group is proposed as a 4D wormhole. This solution has two null hypersurfaces where an interchange of the sign of some 5D metric components happens. For a 4D observer living on the base of this principal bundle this is a wormhole with two asymptotically flat Lorentzian (Euclidean) spacetimes connected by a Euclidean (Lorentzian) throat. The 4D Lorentzian observer sees these two null hypersurfaces as electric charges.

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V. Dzhunushaliev, H. -J. Schmidt. 1999-08-31. 4D Wormhole with Signature Change in the Presence of Extra Dimensions. https://arxiv.org/abs/gr-qc/9908076

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