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arXiv · 1012.5411

Circular motion of neutral test particles in Reissner-Nordstr\"om spacetime

D. Pugliese·H. Quevedo·R. Ruffini
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Abstract

We investigate the motion of neutral test particles in the gravitational field of a mass $M$ with charge $Q$ described by the Reissner-Nordstr\"om (RN) spacetime. We focus on the study of circular stable and unstable orbits around configurations describing either black holes or naked singularities. We show that at the classical radius, defined as $Q^2/M$, there exist orbits with zero angular momentum due to the presence of repulsive gravity. The analysis of the stability of circular orbits indicates that black holes are characterized by a continuous region of stability. In the case of naked singularities, the region of stability can split into two non-connected regions inside which test particles move along stable circular orbits.

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D. Pugliese, H. Quevedo, R. Ruffini. 2010-12-24. Circular motion of neutral test particles in Reissner-Nordstr\"om spacetime. https://doi.org/10.1103/physrevd.83.024021

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