Corrections to the running of gauge couplings due to quantum gravity

TL;DR

This paper discusses quantum gravitational effects on gauge coupling running, highlighting a space-time dimension reduction phenomenon that universally promotes asymptotic freedom, aligning with recent findings.

Contribution

It introduces a quantum-gravitational effect of space-time dimension running that influences gauge coupling behavior, providing a unifying explanation for previous conflicting results.

Findings

Space-time dimension decreases at small scales.

Dimension running induces asymptotic freedom in gauge couplings.

Results agree quantitatively with Robinson and Wilczek's work.

Abstract

Concerning the gravitational corrections to the running of gauge couplings two different results were reported. Some authors claim that gravitational correction at the one-loop level indicates an interesting effect of universal gravitational decreasing of gauge couplings, that is, gravitational correction works universally in the direction of asymptotic freedom no matter how the gauge coupling behaves without gravity, while others reject the presence of gravitational correction at the one-loop level at all. Being these calculations done in the framework of an effective field theory approach to general relativity, we wanted to draw attention to a recently discovered profound quantum-gravitational effect of space-time dimension running that inevitably affects the running of gauge couplings. The running of space-time dimension indicating gradual reduction of dimension as one gets into smaller scales acts on the coupling constants in the direction of asymptotic freedom and therefore in any case manifests the plausibility of this quantum-gravitational effect. Curiously enough, the results are also in perfect quantitative agreement with those of Robinson and Wilczek.