Eur. Phys. J. C (2016) 76: 293
https://doi.org/10.1140/epjc/s10052-016-4141-6

Regular Article - Theoretical Physics

Spin precession in anisotropic cosmologies

¹ Dipartimento di Fisica e Astronomia, Università di Bologna and INFN, via Irnerio 46, 40126, Bologna, Italy
² L. D. Landau Institute for Theoretical Physics, Moscow, 119334, Russia
³ Bogoliubov Laboratory of Theoretical Physics, Joint Institute for Nuclear Research, Dubna, 141980, Russia
⁴ Lomonosov Moscow State University, GSP-1, Leninskie Gory, Moscow, 119991, Russia

^* e-mail: kamenshchik@bo.infn.it

Received: 1 February 2016
Accepted: 14 May 2016
Published online: 24 May 2016

Abstract

We consider the precession of a Dirac particle spin in some anisotropic Bianchi universes. This effect is present already in the Bianchi-I universe. We discuss in some detail the geodesics and the spin precession for both the Kasner and the Heckmann–Schucking solutions. In the Bianchi-IX universe the spin precession acquires the chaotic character due to the stochasticity of the oscillatory approach to the cosmological singularity. The related helicity flip of fermions in the very early universe may produce the sterile particles contributing to dark matter.