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arXiv · 1607.04878

From Planck data to Planck era: Observational tests of Holographic Cosmology

Niayesh Afshordi·Claudio Coriano·Luigi Delle Rose·Elizabeth Gould·Kostas Skenderis
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Abstract

We test a class of holographic models for the very early universe against cosmological observations and find that they are competitive to the standard $Λ$CDM model of cosmology. These models are based on three dimensional perturbative super-renormalizable Quantum Field Theory (QFT), and while they predict a different power spectrum from the standard power-law used in $Λ$CDM, they still provide an excellent fit to data (within their regime of validity). By comparing the Bayesian evidence for the models, we find that $Λ$CDM does a better job globally, while the holographic models provide a (marginally) better fit to data without very low multipoles (i.e. $l\lesssim 30$), where the dual QFT becomes non-perturbative. Observations can be used to exclude some QFT models, while we also find models satisfying all phenomenological constraints: the data rules out the dual theory being Yang-Mills theory coupled to fermions only, but allows for Yang-Mills theory coupled to non-minimal scalars with quartic interactions. Lattice simulations of 3d QFT's can provide non-perturbative predictions for large-angle statistics of the cosmic microwave background, and potentially explain its apparent anomalies.

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Niayesh Afshordi, Claudio Coriano, Luigi Delle Rose, Elizabeth Gould, Kostas Skenderis. 2017-01-03. From Planck data to Planck era: Observational tests of Holographic Cosmology. https://doi.org/10.1103/physrevlett.118.041301

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