Holographic studies of quasi-topological gravity

TL;DR

This paper explores quasi-topological gravity within the holographic framework, establishing duality elements, constraining couplings, and analyzing hydrodynamic properties like shear viscosity in the dual gauge theory.

Contribution

It develops the AdS/CFT dictionary for quasi-topological gravity and investigates its hydrodynamic implications, including a lower bound on shear viscosity.

Findings

Derived constraints on gravitational couplings.

Established holographic duality elements.

Identified minimum shear viscosity-to-entropy ratio.

Abstract

Quasi-topological gravity is a new gravitational theory including curvature-cubed interactions and for which exact black hole solutions were constructed. In a holographic framework, classical quasi-topological gravity can be thought to be dual to the large $N_c$ limit of some non-supersymmetric but conformal gauge theory. We establish various elements of the AdS/CFT dictionary for this duality. This allows us to infer physical constraints on the couplings in the gravitational theory. Further we use holography to investigate hydrodynamic aspects of the dual gauge theory. In particular, we find that the minimum value of the shear-viscosity-to-entropy-density ratio for this model is $\eta/s \simeq 0.4140/(4\pi)$.