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arXiv · 0808.3005

Perturbation Method for Classical Spinning Particle Motion: I. Kerr Space-Time

Dinesh Singh
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Abstract

This paper presents an analytic perturbation approach to the dynamics of a classical spinning particle, according to the Mathisson-Papapetrou-Dixon (MPD) equations of motion, with a direct application to circular motion around a Kerr black hole. The formalism is established in terms of a power series expansion with respect to the particle's spin magnitude, where the particle's kinematic and dynamical degrees are expressed in a completely general form that can be constructed to infinite order in the expansion parameter. It is further shown that the particle's squared mass and spin magnitude can shift due to a classical analogue of radiative corrections that arise from spin-curvature coupling. Explicit expressions are determined for the case of circular motion near the event horizon a Kerr black hole, where the mass and spin shift contributions are dependent on the initial conditions of the particle's spin orientation. A preliminary analysis of the stability properties of the orbital motion in the Kerr background due to spin-curvature interactions is explored and briefly discussed.

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Dinesh Singh. 2008-10-07. Perturbation Method for Classical Spinning Particle Motion: I. Kerr Space-Time. https://doi.org/10.1103/physrevd.78.104028

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