The correlation of WGC and Hydrodynamics bound with $R^4$ correction in the charged AdS$_{d+2}$ black brane

Abstract

In this paper, we focus on the possible correlation between conjectures KSS bound and weak gravity conjecture (WGC). The hydrodynamic values KSS bound and weak gravity conjecture constraint the low-energy effective field theory. These conjectures identify UV complete theories. We give four, six and eight order derivative corrections to corresponding action and employ the hyperscaling violating charged AdS$_{d+2}$ black brane solution. These corrections lead us to find correlation between conjectures KSS bound and weak gravity conjecture. We see that, with increasing perturbation correction, this correlation is more likely to appear. We consider dynamical constant $z=1$, $d=5$ and obtain the range of hyperscaling violation exponent $d+z-2\leq\theta\leq d+z-1$ for the above mentioned black brane. Here, we show that higher derivative corrections reduce the ratio of $\frac{M}{Q}$ to extremal black holes. Likewise, we also obtain the universal relaxation bound $\tau\geq \frac{1}{\pi T}$ and KSS bound $\frac{\eta}{s}\geq \frac{1}{4\pi}$ for our model. The results indicate that there is a possibility of a relationship between the two conjectures. Our studies also show the consistency of the WGC and the KSS bound conjectures for all corrections (except curvature-cubed, $\beta_2$) in the extremal and near-extremal condition.