Dirac Particles in a Gravitational Field

TL;DR

This paper explores the semiclassical Hamiltonian of Dirac particles in dynamic gravitational fields, revealing new couplings affecting energy and particle-antiparticle symmetry.

Contribution

It introduces a new semiclassical Hamiltonian framework accounting for time-dependent metrics and identifies novel couplings between momentum, spin, and gravitational effects.

Findings

Discovered a new coupling between linear momentum and spin.

Identified contributions to particle-antiparticle symmetry breaking.

Extended previous static metric models to dynamic gravitational fields.

Abstract

The semiclassical approximation for the Hamiltonian of Dirac particles interacting with an arbitrary gravitational field is investigated. The time dependence of the metrics leads to new contributions to the in-band energy operator in comparison to previous works on the static case. In particular we find a new coupling term between the linear momentum and the spin, as well as couplings which contribute to the breaking of the particle - antiparticle symmetry.