Quantum Gravity Phenomenology in the Infrared

TL;DR

This paper explores how quantum gravity, particularly via metastring theory, could influence cosmological phenomena and infrared physics, potentially offering new insights into dark matter and dark energy without violating Lorentz symmetry.

Contribution

It proposes a novel quantum gravity framework based on metastring theory that impacts infrared cosmology and allows for a fundamental length scale without breaking Lorentz invariance.

Findings

Infrared modifications from quantum gravity could influence Universe evolution

Metastring theory enables a fundamental length scale without Lorentz symmetry breaking

Potential new sources for dark matter and dark energy

Abstract

Quantum gravity effects are traditionally tied to short distances and high energies. In this essay we argue that, perhaps surprisingly, quantum gravity may have important consequences for the phenomenology of the infrared. We center our discussion around a conception of quantum gravity involving a notion of quantum spacetime that arises in metastring theory. This theory allows for an evolution of a cosmological Universe in which string-dual degrees of freedom decouple as the Universe ages. Importantly such an implementation of quantum gravity allows for the inclusion of a fundamental length scale without introducing the fundamental breaking of Lorentz symmetry. The mechanism seems to have potential for an entirely novel source for dark matter/energy. The simplest observational consequences of this scenario may very well be residual infrared modifications that emerge through the evolution of the Universe.