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arXiv · 2209.07543

Interferometer Response to Geontropic Fluctuations

Abstract

We model vacuum fluctuations in quantum gravity with a scalar field, characterized by a high occupation number, coupled to the metric. The occupation number of the scalar is given by a thermal density matrix, whose form is motivated by fluctuations in the vacuum energy, which have been shown to be conformal near a light-sheet horizon. For the experimental measurement of interest in an interferometer, the size of the energy fluctuations is fixed by the area of a surface bounding the volume of spacetime being interrogated by an interferometer. We compute the interferometer response to these "geontropic" scalar-metric fluctuations, and apply our results to current and future interferometer measurements, such as LIGO and the proposed GQuEST experiment.

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BibTeXRIS

Dongjun Li, Vincent S. H. Lee, Yanbei Chen, Kathryn M. Zurek. 2022-09-15. Interferometer Response to Geontropic Fluctuations. https://doi.org/10.1103/physrevd.107.024002

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