Massive gravity with Lorentz symmetry breaking: black holes as heat engines

In extended phase space, a static black hole in massive gravity is studied as a holographic heat engine. In the massive gravity theory considered, the graviton gain a mass due to Lorentz symmetry breaking. Exact efficiency formula is obtained for a rectangle engine cycle for the black hole considered. The efficiency is computed by varying two parameters in the theory, the scalar charge Q and $\lambda$. The efficiency is compared with the Carnot efficiency for the heat engine. It is observed that when Q and $\lambda$ are increased that the efficiency for the rectangle cycle increases. When compared to the Schwarzschild AdS black hole, the efficiency for the rectangle cycle is larger for the Massive gravity black hole.