Effective Low-Energy Potential for Slow Dirac Fermions in Einstein-Cartan Gravity with Torsion and Chameleon

TL;DR

This paper derives a comprehensive low-energy potential for slow Dirac fermions interacting with gravitational, chameleon, and torsion fields within Einstein-Cartan gravity, facilitating experimental tests of these interactions.

Contribution

It provides the most general effective low-energy potential to order O(1/m) for Dirac fermions in curved spacetime with torsion and chameleon fields, extending previous models.

Findings

Derived the effective potential including torsion and chameleon effects.

Extended the metric to incorporate chameleon fields in rotating frames.

Discussed experimental implications for torsion and gravitational interactions.

Abstract

We derive the most general effective low-energy potential to order O(1/m) for slow Dirac fermions with mass m, coupled to gravitational, chameleon and torsion fields in the Einstein-Cartan gravity. The obtained results can be applied to the experimental analysis of gravitational, chameleon and torsion interactions in terrestrial laboratories. We discuss the use of rotating coordinate systems, caused by rotations of devices, for measurements of the torsion vector and tensor components, caused by minimal torsion--fermion couplings (Ivanov and Wellenzohn, Phys. Rev. D92, 065006 (2015)). Using the most general form of a metric tensor of curved spacetimes in rotating coordinate systems, proposed by Obukhov, Silenko, and Teryaev (Phys. Rev. D84, 024025 (2011)), we extend this metric by the inclusion of the chameleon field and calculate the set of vierbein fields, in terms of which Dirac fermions couple to torsion vector and tensor components through minimal torsion-fermion couplings. For such a set of vierbein fields we discuss a part of the effective low-energy potential for slow Dirac fermions, coupled to gravitational, chameleon and torsion fields to order O(1) in the large fermion mass expansion.