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Updated: Jun 25, 2026

Generation and Coherent Control of Pulsed Quantum Frequency Combs
Published on: June 8, 2018
Cosmological footprints of loop quantum gravity
1AstroParticule et Cosmologie, Université Paris 7, CNRS, IN2P3 10, rue Alice Domon et Léonie Duquet, 75205 Paris cedex 13, France. grain@apc.univ-paris7.fr
Abstract:
The primordial spectrum of cosmological tensor perturbations is considered as a possible probe of quantum gravity effects. Together with string theory, loop quantum gravity is one of the most promising frameworks to study quantum effects in the early universe. We show that the associated corrections should modify the potential seen by gravitational waves during the inflationary amplification. The resulting power spectrum should exhibit a characteristic tilt. This opens a new window for cosmological tests of quantum gravity.
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