On the Interpretation of Thermal Conductance of the nu=5/2 Edge

Recent experiments [Banerjee et al, Nature 2018] have measured thermal conductance of the $\nu=5/2$ edge in a GaAs electron gas and found it to be quantized as $K \approx 5/2$ (in appropriate dimensionless units). This result is unexpected, as prior numerical work predicts that the $\nu=5/2$ state should be the Anti-Pfaffian phase of matter, which should have quantized $K=3/2$. The purpose of this paper is to propose a possible solution to this conflict: if the Majorana edge mode of the Anti-Pfaffian does not thermally equilibrate with the other edge modes, then $K=5/2$ is expected. I discuss several possible reasons for this nonequilibration, and discuss possible mechanisms in some detail. I further discuss what should be examined further to determine if this is the case.