Macroscopic Parity Nonconservation Due to Neutral Currents?

The parity-nonconserving electron-nucleon interaction induced by neutral currents should give rise to a (thermodynamically stable) electric-dipole-moment density directed along the characteristic rotation axis $\hat{\omega }$ of superfluid ${}_{}{}^3{}_{}{}^{}\mathrm{He}$-$B$; if observed, this would constitute the first example of parity nonconservation on a macroscopic scale. Although the magnitude of the effect depends critically on a poorly known chemical parameter, it quite probably lies within the experimentally detectable range.