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A Note on Real Tunneling Geometries

S. Carlip
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Abstract

In the Hartle-Hawking ``no boundary'' approach to quantum cosmology, a real tunneling geometry is a configuration that represents a transition from a compact Riemannian spacetime to a Lorentzian universe. I complete an earlier proof that in three spacetime dimensions, such a transition is ``probable,'' in the sense that the required Riemannian geometry yields a genuine maximum of the semiclassical wave function.

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S. Carlip. 2005-08-17. A Note on Real Tunneling Geometries. https://doi.org/10.1088/0264-9381%2F22%2F20%2Fn03

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