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arXiv · 2012.00170

Stochastic gravitational-wave background in quantum gravity

Gianluca Calcagni·Sachiko Kuroyanagi
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Abstract

Among all cosmological quantum-gravity or quantum-gravity-inspired scenarios, only very few predict a blue-tilted primordial tensor spectrum. We explore five of them and check whether they can generate a stochastic gravitational-wave background detectable by present and future interferometers: non-local quantum gravity, string-gas cosmology, new ekpyrotic scenario, Brandenberger-Ho non-commutative inflation and multi-fractional spacetimes. We show that non-local quantum gravity is unobservable, while all the other models can reach the strain sensitivity of DECIGO but not that of LIGO-Virgo-KAGRA, LISA or Einstein Telescope. Other quantum-gravity models with red-tilted spectra (most loop quantum cosmologies) or with exceptionally tiny quantum corrections (Wheeler-DeWitt quantum cosmology) are found to be non-detectable.

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BibTeXRIS

Gianluca Calcagni, Sachiko Kuroyanagi. 2020-11-30. Stochastic gravitational-wave background in quantum gravity. https://doi.org/10.1088/1475-7516/2021/03/019

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