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arXiv · 0812.1298

Einstein-Cartan gravity with Holst term and fermions

Marcin Kaźmierczak
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Abstract

We investigate the consequences of the ambiguity of minimal coupling procedure for Einstein-Cartan gravity with Holst term and fermions. A new insight is provided into the nature and physical relevance of coupling procedures considered hitherto in the context of Ashtekar-Barbero-Immirzi formalism with fermions. The issue of physical effects of the Immirzi parameter in semi--classical theory is reinvestigated. We argue that the conclusive answer to the question of its measurability will not be possible until the more fundamental problem of nonuniqueness of gravity--induced fermion interaction in Einstein-Cartan theory is solved.

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Marcin Kaźmierczak. 2009-03-25. Einstein-Cartan gravity with Holst term and fermions. https://doi.org/10.1103/physrevd.79.064029

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