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An Anisotropic Wormhole:TUNNELLING in Time and Space

M. Cavaglia' V. de Alfaro·F. de Felice
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Abstract

We discuss the structure of a gravitational euclidean instanton obtained through coupling of gravity to electromagnetism. Its topology at fixed $t$ is $S^1\times S^2$. This euclidean solution can be interpreted as a tunnelling to a hyperbolic space (baby universe) at $t=0$ or alternatively as a static wormhole that joins the two asymptotically flat spaces of a Reissner--Nordström type solution with $M=0$.

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M. Cavaglia' V. de Alfaro, F. de Felice. 1993-01-27. An Anisotropic Wormhole:TUNNELLING in Time and Space. https://doi.org/10.1103/physrevd.49.6493

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