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arXiv · 1001.4925

Vacuum tunneling in gravity

Y. M. Cho·D. G. Pak
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Abstract

Topologically non-trivial vacuum structure in gravity models with Cartan variables (vielbein and contortion) is considered. We study the possibility of vacuum space-time tunneling in Einstein gravity assuming that the vielbein may play a fundamental role in quantum gravitational phenomena. It has been shown that in the case of RP3 space topology the tunneling between non-trivial topological vacuums can be realized by means of Eguchi-Hanson gravitational instanton. In Riemann-Cartan geometric approach to quantum gravity the vacuum tunneling can be provided by means of contortion quantum fluctuations. We define double self-duality condition for the contortion and give explicit self-dual configurations which can contribute to vacuum tunneling amplitude.

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Y. M. Cho, D. G. Pak. 2011-07-03. Vacuum tunneling in gravity. https://doi.org/10.1088/0264-9381%2F28%2F15%2F155008

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