Holography for Cosmology

TL;DR

This paper develops a holographic framework linking four-dimensional inflationary universes to three-dimensional quantum field theories, enabling new insights into cosmological observables and potential models consistent with current data.

Contribution

It introduces a holographic description of inflationary universes that captures cosmological observables through three-dimensional QFT correlation functions, applicable in both weak and strong gravity regimes.

Findings

Holographic description reproduces standard inflationary predictions.

Models with two parameters can satisfy observational constraints.

Proposes a phenomenological approach to holographic cosmology.

Abstract

We propose a holographic description of four-dimensional single-scalar inflationary universes, and show how cosmological observables, such as the primordial power spectrum, are encoded in the correlation functions of a three-dimensional QFT. The holographic description correctly reproduces standard inflationary predictions in the limit where a perturbative quantization of fluctuations is justified. In the opposite limit, wherein gravity is strongly coupled at early times, we propose a holographic description in terms of perturbative large N QFT. Initiating a holographic phenomenological approach, we show that models containing only two parameters, N and a dimensionful coupling constant, are capable of satisfying the current observational constraints.