Astrophysical implications of the Asymptotic Safety Scenario in Quantum Gravity

TL;DR

This paper explores how the asymptotic safety scenario in quantum gravity impacts astrophysics, suggesting quantum effects influence universe entropy, inflation, and black hole remnants, with implications for cosmology and black hole physics.

Contribution

It reviews recent renormalization group improved cosmologies based on Quantum Einstein Gravity and discusses their astrophysical implications, including universe entropy and black hole remnants.

Findings

Quantum effects may account for the universe's entire entropy.

Quantum gravity predicts a Planck-sized remnant after black hole evaporation.

Inflationary expansion can arise from quantum effects in the early universe.

Abstract

In recent years it has emerged that the high energy behavior of gravity could be governed by an ultraviolet non-Gaussian fixed point of the (dimensionless) Newton's constant, whose behavior at high energy is thus {\it antiscreened}. This phenomenon has several astrophysical implications. In particular in this article recent works on renormalization group improved cosmologies based upon a renormalization group trajectory of Quantum Einstein Gravity with realistic parameter values will be reviewed. It will be argued that quantum effects can account for the entire entropy of the present Universe in the massless sector and give rise to a phase of inflationary expansion. Moreover the prediction for the final state of the black hole evaporation is a Planck size remnant which is formed in an infinite time.