Perturbation Method for Classical Spinning Particle Motion: II. Vaidya Space-Time

TL;DR

This paper applies perturbation methods to analyze the motion of spinning particles in Vaidya space-time, revealing how mass accretion or loss affects orbital dynamics and stability near black holes.

Contribution

It extends the MPD equations to Vaidya space-time, providing new insights into spinning particle behavior in non-stationary black hole environments.

Findings

Mass accretion influences spin and mass evolution of particles.

Orbital stability is affected by spin-curvature interactions.

Results align with previous Kerr black hole studies.

Abstract

This paper describes an application of the Mathisson-Papapetrou-Dixon (MPD) equations in analytic perturbation form to the case of circular motion around a radially accreting or radiating black hole described by the Vaidya metric. Based on the formalism presented earlier, this paper explores the effects of mass accretion or loss of the central body on the overall dynamics of the orbiting spinning particle. This includes changes to its squared mass and spin magnitude due to the classical analog of radiative corrections from spin-curvature coupling. Various quantitative consequences are explored when considering orbital motion near the black hole's event horizon. An analysis on the orbital stability properties due to spin-curvature interactions is examined briefly, with conclusions in general agreement with previous work performed for the case of circular motion around a Kerr black hole.