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arXiv · 1012.1270

Dirac fields in f(R)-gravity with torsion

Luca Fabbri·Stefano Vignolo
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Abstract

We study f(R)-gravity with torsion in presence of Dirac massive fields. Using the Bianchi identities, we formulate the conservation laws of the theory and we check the consistency with the matter field equations. Further, we decompose the field equations in torsionless and torsional terms: we show that the non-linearity of the gravitational Lagrangian reduces to the presence of a scalar field that depends on the spinor field; this additional scalar field gives rise to an effective stress-energy tensor and plays the role of a scale factor modifying the normalization of Dirac fields. Problems for fermions regarding the positivity of energy and the particle-antiparticle duality are discussed.

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Luca Fabbri, Stefano Vignolo. 2011-05-05. Dirac fields in f(R)-gravity with torsion. https://doi.org/10.1088/0264-9381%2F28%2F12%2F125002

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