Eur. Phys. J. C (2008) 56: 607-612
https://doi.org/10.1140/epjc/s10052-008-0693-4

Regular Article - Theoretical Physics

Torsion-induced spin precession

Physics Department, Payame Noor University, 19395-4697, Tehran, Iran

^* e-mail: m-mohseni@pnu.ac.ir

Received: 1 July 2008
Revised: 22 July 2008
Published online: 22 August 2008

Abstract

We investigate the motion of a spinning test particle in a spatially-flat FRW-type space-time in the framework of the Einstein–Cartan theory. The space-time has a torsion arising from a spinning fluid filling the space-time. We show that, for spinning particles with non-zero transverse spin components, the torsion induces a precession of the particle spin around the direction of the spin of the fluid. We also show that a charged spinning particle moving in a torsion-less spatially-flat FRW space-time in the presence of a uniform magnetic field undergoes a precession of a different character.