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arXiv · 0802.1221

Immirzi parameter and fermions with non-minimal coupling

Sergei Alexandrov
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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.

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Sergei Alexandrov. 2008-06-16. Immirzi parameter and fermions with non-minimal coupling. https://doi.org/10.1088/0264-9381%2F25%2F14%2F145012

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