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Dirac Theory in Space-Time without Torsion

Ludger Hannibal
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Abstract

It is proven that the usual quadratic general-covariant Lagrangian for the Dirac field leads to a symmetric, divergence-free energy-momentum tensor in the standard Riemannian framework of space-time without torsion, provided the tetrad field components are the only quantities related to gravitation that are varied independently.

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Ludger Hannibal. 1994-12-09. Dirac Theory in Space-Time without Torsion. https://arxiv.org/abs/gr-qc/9412026

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