An Holographic Cosmology

TL;DR

This paper introduces a holographic cosmology model where the early universe is dominated by a dense black hole gas, leading to scale-invariant fluctuations and offering alternative solutions to classical cosmological problems.

Contribution

It proposes a novel holographic framework for cosmology with a dense black hole phase, providing new insights into fluctuation spectra and monopole problem solutions.

Findings

Quantum fluctuations produce a scale-invariant spectrum of density perturbations.

The model predicts a relic density of charged extremal black monopoles.

A potential issue with the predicted scale range matching observations is identified.

Abstract

We present a new cosmological model, based on the holographic principle, which shares many of the virtues of inflation. The very earliest semiclassical era of the universe is dominated by a dense gas of black holes, with equation of state $p=\rho$. Fluctuations lead to an instability to a phase with a dilute gas of black holes, which later decays via Hawking radiation to a radiation dominated universe. The quantum fluctuations of the initial state give rise to a scale invariant spectrum of density perturbations, for a range of scales. We point out a problem, that appears to prevent the range of scales predicted by the model from coinciding with the range where such a spectrum has been observed. We speculate that this may be related to our field theoretic treatment of fluctuations in the highly holographic $p=\rho$ background. The monopole problem is solved in a manner completely different from inflationary models, and a relic density of highly charged extremal black monopoles is predicted. We discuss the nature of the entropy and flatness problems in our model.