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arXiv · 2405.13784

Revisiting the dynamics of a charged spinning body in curved spacetime

K. Andrzejewski
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Abstract

We analyse the motion of the spinning body (in the pole-dipole approximation) in the gravitational and electromagnetic fields described by the Mathisson-Papapetrou-Dixon-Souriau equations. First, we define a novel spin condition for the body with the magnetic dipole moment proportional to spin, which generalizes the one proposed by Ohashi-Kyrian-Semer\'ak for gravity. As a result, we get the whole family of charged spinning particle models in the curved spacetime with remarkably simple dynamics (momentum and velocity are parallel). Applying the reparametrization procedure, for a specific dipole moment, we obtain equations of motion with constant mass and gyromagnetic factor. Next, we show that these equations follow from an effective Hamiltonian formalism, previously interpreted as a classical model of the charged Dirac particle.

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K. Andrzejewski. 2024-05-22. Revisiting the dynamics of a charged spinning body in curved spacetime. https://doi.org/10.1088/1361-6382/adb2d4

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