Electric hyperscaling violating solutions in Einstein-Maxwell-dilaton gravity with R^2 corrections

Understand

In the context of holography applied to condensed matter physics, we study Einstein-Maxwell-dilaton theory with curvature squared corrections.

• This theory has three couplings eta_i for the three R^2 invariants and two theory functions: a dilaton potential V(phi) and a dilaton-dependent gauge coupling f(phi).
• We find hyperscaling violating solutions of this theory, parametrized by dynamical critical exponent z and HSV parameter theta.
• We obtain restrictions on the form of the theory functions required to support HSV-type solutions using three physical inputs: the null energy condition, causality z $\leq$ 1, and d_eff = d - theta lying in the range 0 < d_eff $\leq$ d.