Thermal Nieh-Yan anomaly in Weyl superfluids

We discuss the possibility of torsional Nieh-Yan anomaly of the type partial derivative(mu) (ej(5)(mu)) = gamma T-2 (T-a Lambda T-a) in Weyl superfluids, where T is the infrared (IR) temperature scale and T a is the effective or emergent torsion from the superfluid order parameter. As distinct from the dimensionful ultraviolet (UV) parameter Lambda(2) in the conventional torsional Nieh-Yan anomaly, the parameter gamma is dimensionless in canonical units. This suggests that such dimensionless parameter may be fundamental, being determined by the geometry, topology, and number of chiral quantum fields in the system. By comparing this to a Weyl superfluid with low-temperature corrections, T