Backreaction effects due to matter coupled higher derivative gravity

TL;DR

This paper investigates how matter coupled higher derivative gravity corrections influence the backreaction on the metric and affect transport properties like shear viscosity and entropy density in AdS-hydrodynamics, relevant for understanding quark-gluon plasma.

Contribution

It provides the first detailed calculation of backreaction effects in matter coupled higher derivative AdS gravity and their impact on shear viscosity and entropy density.

Findings

Backreaction corrections to the metric are derived.

Shear viscosity $ta$ receives quantifiable corrections.

Entropy density $s$ is affected by higher derivative terms.

Abstract

AdS-hydrodynamics has proven to be a useful tool for obtaining transport coefficients observed in the collective flow of strongly coupled fluids like quark gluon plasma (QGP). Particularly, the ratio of shear viscosity to entropy density ${\eta/ s}$ obtained from elliptic flow measurements can be matched with the computation done in the dual gravity theory. The experimentally observed temperature dependence of ${\eta/ s}$ requires the study of scalar matter coupled AdS gravity including higher derivative curvature corrections. We obtain the backreaction to the metric for such a matter coupled AdS gravity in $D$-dimensional spacetime due to the higher derivative curvature corrections. Then, we present the backreaction corrections to shear-viscosity $\eta$ and entropy density $s$.