Holographic universal relations among transport coefficients

Abstract

In this paper, we show universal relations among the transport coefficients by calculating the electrical conductivity, thermal conductivity and thermo-electric conductivity in the presence of a chemical potential and magnetic fields for Einstein-Maxwell-dilaton-axion system in arbitrary but even dimensional bulk spacetime as well as for Einstein-DBI-dilaton-axion system in $3+1$ dimensional bulk spacetime. Moreover, we have also obtained a new hyperscale violating black hole solution with finite charge density and magnetic fields but with a trivial dilaton field at IR.