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arXiv · 1407.6026

Creation of wormholes by quantum tunnelling in modified gravity theories

Lorenzo Battarra·George Lavrelashvili·Jean-Luc Lehners
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Abstract

We study the process of quantum tunnelling in scalar-tensor theories in which the scalar field is non-minimally coupled to gravity. In these theories gravitational instantons can deviate substantially from sphericity and can in fact develop a neck - a feature prohibited in theories with minimal coupling. Such instantons with necks lead to the materialisation of bubble geometries containing a wormhole region. We clarify the relationship of neck geometries to violations of the null energy condition, and also derive a bound on the size of the neck relative to that of the instanton.

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Lorenzo Battarra, George Lavrelashvili, Jean-Luc Lehners. 2014-11-06. Creation of wormholes by quantum tunnelling in modified gravity theories. https://doi.org/10.1103/physrevd.90.124015

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