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Title: Bound on quantum fluctuations in gravitational waves from LIGO-Virgo
Abstract We derive some of the central equations governing quantum fluctuations in gravitational waves, making use of general relativity as a sensible effective quantum theory at large distances. We begin with a review of classical gravitational waves in general relativity, including the energy in each mode. We then form the quantum ground state and coherent state, before then obtaining an explicit class of squeezed states. Since existing gravitational wave detections arise from merging black holes, and since the quantum nature of black holes remains puzzling, one can be open-minded to the possibility that the wave is in an interesting quantum mechanical state, such as a highly squeezed state. We compute the time and space two-point correlation functions for the quantized metric perturbations. We then constrain its amplitude with LIGO-Virgo observations. Using existing LIGO-Virgo data, we place a bound on the (exponential) squeezing parameter of the quantum gravitational wave state of ζ< 41.  more » « less
Award ID(s):
2013953
PAR ID:
10475209
Author(s) / Creator(s):
;
Publisher / Repository:
Journal of Cosmology and Astroparticle Physics
Date Published:
Journal Name:
Journal of Cosmology and Astroparticle Physics
Volume:
2023
Issue:
03
ISSN:
1475-7516
Page Range / eLocation ID:
009
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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