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arXiv · 2102.02048

Imprints from a Riemann-Cartan space-time on the energy levels of Dirac spinors

Francisco Cabral·Francisco S. N. Lobo·Diego Rubiera-Garcia
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Abstract

In this work, we investigate the effects of the torsion-fermionic interaction on the energy levels of fermions within a Riemann-Cartan geometry using a model-independent approach. We consider the case of fermions minimally coupled to the background torsion as well as non-minimal extensions via additional couplings with the vector and axial fermionic currents which include parity-breaking interactions. In the limit of zero-curvature, and for the cases of constant and spherically symmetric torsion, we find a Zeeman-like effect on the energy levels of fermions and anti-fermions depending on whether they are aligned/anti-aligned with respect to the axial vector part of the torsion (or to specific combination of torsion quantities), and determine the corresponding fine-structure energy transitions. We also discuss non-minimal couplings between fermionic fields and torsion within the Einstein-Cartan theory and its extension to include the (parity-breaking) Holst term. Finally we elaborate on the detection of torsion effects related to the splitting of energy levels in astrophysics, cosmology and solid state physics using current capabilities.

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Francisco Cabral, Francisco S. N. Lobo, Diego Rubiera-Garcia. 2021-02-03. Imprints from a Riemann-Cartan space-time on the energy levels of Dirac spinors. https://doi.org/10.1088/1361-6382%2Fac1cca

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