Spinning test particle motion around a rotating wormhole

TL;DR

This paper studies how spinning test particles move around a rotating wormhole, revealing how spins influence the innermost stable orbit and effective potential, with results differing from black hole cases.

Contribution

It extends previous work by analyzing spinning particle motion in a rotating wormhole using Mathisson-Papapetrou-Dixon equations, highlighting the effects of spins on orbits and stability.

Findings

The ISCO location depends significantly on particle and wormhole spins.

Effective potential has two configurations: plus and minus.

The ISCO increases with wormhole spin, unlike in black holes.

Abstract

In this work, we investigated the motion of spinning test particles around a rotating wormhole, extending, in this way, the previous work of Benavides-Gallego et al. in [Phys. Rev. D 101, no.12, 124024] to the general case. Using the Mathisson-Papapetrous-Dixon equations, we study the effective potential, circular orbits, and the innermost stable circular orbit (ISCO) of spinning test particles. We found that both the particle and wormhole spins affect the location of the ISCO significantly. On the other hand, Similar to the non-rotating case, we also found two possible configurations in the effective potential: plus and minus. Furthermore, the minimum value of the effective potential is not at the throat due to its spin, in contrast to the motion of the non-spinning test particles in a non-rotating wormhole, where the effective potential is symmetric, and its minimum value is at the throat. In the case of the ISCO, we found that it increases as the spin of the wormhole a increases, in contrast to black holes where the presence of spin decreases the value of the ISCO. Finally, since the dynamical four-momentum and kinematical four-velocity of the spinning particle are not always parallel, we consider the superluminal bound, finding that the allowed values of s change as the wormhole's spin a increases.