Thermodynamical properties of black holes in gravitational theories
without local Lorentz invariance have been subject to intense
investigation in past years due to the presence of universal horizons,
which are strong causal barriers even for superluminal signals. Here we
present a novel general method for deriving the Smarr formula for this
class of theories: in particular we show that the Smarr formulas for
Einsteinther theory and infrared Ho. rava gravity follow from scale
invariance. We not only reproduce straightforwardly previous findings
for static black hole solutions, but we are also able to generalize them
to the case of stationary rotating black holes. Finally, we apply our
results to the rotating black holes with universal horizon as found in
three dimensions, from which we shall draw some lessons on the viability
of black hole thermodynamics for black hole solutions endowed with
universal horizons.
