Detecting quantum gravity in the sky

Gianluca Calcagni

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arXiv · 1709.07845

Detecting quantum gravity in the sky

Gianluca Calcagni

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Abstract

Getting signatures of quantum gravity is one of the topical lines of research in modern theoretical physics and cosmology. This short review faces this challenge under a novel perspective. Instead of separating quantum-gravity effects of a specific model between UV and IR regimes, we consider a general feature, possibly common to many frameworks, where all scales are affected and spacetime geometry is characterized by a complex critical exponent. This leaves a log-oscillating modulation pattern in the cosmic microwave background spectrum and gives a unique opportunity, illustrated with the example of a multi-fractional theory, to test quantum gravities at cosmological scales.

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Gianluca Calcagni. 2017-09-22. Detecting quantum gravity in the sky. https://arxiv.org/abs/1709.07845

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