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arXiv · 2106.13811

Matter matters in Einstein-Cartan gravity

Georgios K. Karananas·Mikhail Shaposhnikov·Andrey Shkerin·Sebastian Zell
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Abstract

We study scalar, fermionic and gauge fields coupled nonminimally to gravity in the Einstein-Cartan formulation. We construct a wide class of models with nondynamical torsion whose gravitational spectra comprise only the massless graviton. Eliminating non-propagating degrees of freedom, we derive an equivalent theory in the metric formulation of gravity. It features contact interactions of a certain form between and among the matter and gauge currents. We also discuss briefly the inclusion of curvature-squared terms.

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Georgios K. Karananas, Mikhail Shaposhnikov, Andrey Shkerin, Sebastian Zell. 2021-06-25. Matter matters in Einstein-Cartan gravity. https://doi.org/10.1103/physrevd.104.064036

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