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arXiv · 1804.01102

Damped perturbations in the no-boundary state

Juan Diaz Dorronsoro·Jonathan J. Halliwell·James B. Hartle·Thomas Hertog·Oliver Janssen·Yannick Vreys
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Abstract

We evaluate the no-boundary path integral exactly in a Bianchi IX minisuperspace with two scale factors. In this model the no-boundary proposal can be implemented by requiring one scale factor to be zero initially together with a judiciously chosen regularity condition on the momentum conjugate to the second scale factor. Taking into account the non-linear backreaction of the perturbations we recover the predictions of the original semiclassical no-boundary proposal. In particular we find that large perturbations are strongly damped, consistent with vacuum state wave functions.

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Juan Diaz Dorronsoro, Jonathan J. Halliwell, James B. Hartle, Thomas Hertog, Oliver Janssen, Yannick Vreys. 2018-09-10. Damped perturbations in the no-boundary state. https://doi.org/10.1103/physrevlett.121.081302

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