Fig. 2: Efficiency vs. temperature ratio.
From: Heat engines for scale invariant systems dual to black holes
This plots shows the efficiency η as a function of t ≡ Th/Tc for Stirling (red) and Carnot (blue) engines in D = 4. The solid lines correspond to a monatomic ideal gas (f = 3) and the dashed line to a CFT on a plane. The fixed compression ratio for Stirling is v ≡ V2/V1 = 2.
