Nonminimal hints for asymptotic safety

TL;DR

This paper investigates the role of nonminimal derivative interactions in the asymptotic safety scenario for gravity, finding evidence that such interactions do not destabilize the fixed point, thus supporting the viability of asymptotic safety.

Contribution

It demonstrates the existence and stability of a nonminimal fixed point in gravity-matter systems, extending the understanding of asymptotic safety with matter interactions.

Findings

Discovery of an interacting fixed point for nonminimal couplings.

Indications that nonminimal interactions do not destabilize the fixed point.

Strengthening the case for asymptotic safety in gravity-matter systems.

Abstract

In the asymptotic-safety scenario for gravity, nonzero interactions are present in the ultraviolet. This property should also percolate into the matter sector. Symmetry- based arguments suggest that nonminimal derivative interactions of scalars with curvature tensors should therefore be present in the ultraviolet regime. We perform a nonminimal test of the viability of the asymptotic-safety scenario by working in a truncation of the Renormalization Group flow, where we discover the existence of an interacting fixed point for a corresponding nonminimal coupling. The back-coupling of such nonminimal interactions could in turn destroy the asymptotically safe fixed point in the gravity sector. As a key finding, we observe nontrivial indications of stability of the fixed-point properties under the impact of nonminimal derivative interactions, further strengthening the case for asymptotic safety in gravity-matter systems.