Immirzi parameter and fermions with non-minimal coupling
arXiv:0802.1221 · doi:10.1088/0264-9381/25/14/145012
Abstract
We clarify the role played by the Immirzi parameter in classical gravity coupled to fermions. Considering the general non-minimal coupling, we show that, although the torsion depends explicitly on the Immirzi parameter, in a suitable parametrization the effective action obtained by integrating out the spin-connection is independent of it. Thus the Immirzi parameter is not detectable in classical theory even after coupling of fermions.
4 pages