A window to quantum gravity phenomena in the emergence of the seeds of cosmic structure

TL;DR

This paper critiques the standard inflationary cosmology framework for the origin of cosmic structure seeds, highlighting the need for new physics, and explores a quantum gravity-inspired collapse mechanism as a potential solution.

Contribution

It proposes a novel approach based on Penrose's ideas that quantum gravity could induce wave function collapse, addressing symmetry-breaking issues in cosmic structure formation.

Findings

Standard models assume symmetry-breaking without explicit mechanisms.

Quantum gravity-induced collapse could produce observable differences.

The approach offers a new perspective on the origin of cosmic inhomogeneities.

Abstract

Inflationary cosmology has, in the last few years,received a strong dose of support from observations. The fact that the fluctuation spectrum can be extracted from the inflationary scenario through an analysis that involves quantum field theory in curved space-time, and that it coincides with the observational data has lead to a certain complacency in the community, which prevents the critical analysis of the obscure spots in the derivation. We argue here briefly, as we have discussed in more detail elsewhere, that there is something important missing in our understanding of the origin of the seeds of Cosmic Structure, as is evidenced by the fact that in the standard accounts the inhomogeneity and anisotropy of our universe seems to emerge from an exactly homogeneous andisotropic initial state through processes that do not break those symmetries. This article gives a very brief recount of the problems faced by the arguments based on established physics. The conclusion is that we need some new physics to be able to fully address the problem. The article then exposes one avenue that has been used to address the central issue and elaborates on the degree to which, the new approach makes different predictions from the standard analyses. The approach is inspired on Penrose's proposals that Quantum Gravity might lead to a real, dynamical collapse of the wave function, a process that we argued has the properties needed to extract us from the theoretical impasse described above.