Entangled states, Lorentz transformations, Spin-precession in magnetic fields

TL;DR

This paper investigates how entangled spin-1/2 particles behave under Lorentz transformations and magnetic fields, analyzing effects on entanglement, correlations, and spin precession with considerations of charge and magnetic moments.

Contribution

It provides a compact derivation of Lorentz transformation effects on entangled states and explores combined electric and magnetic field scenarios, highlighting analogies and differences.

Findings

Lorentz transformations affect entangled states in specific, predictable ways.

Magnetic fields induce spin precession depending on particle momentum.

Entanglement and correlations are influenced by relativistic and electromagnetic effects.

Abstract

Two positive mass, spin $\frac 12$ particles created in an entangled state are studied in the presence of a constant magnetic field inducing distinct precessions, depending on the respective momenta, of the two spins. The charge and anomalous magnetic moment of each particle is taken into account. Consequences for entanglement and, more generally, on correlations, are derived. We start, however, with a compact derivation of the effects of Lorentz transformations on such entangled states, though that has been studied by several authors. Our formalism displays conveniently the analogies and the differences between the two cases. Moreover, combining the two, one obtains the case of constant, orthogonal electric and magnetic fields. More general perspectives are evoked in the concluding remarks.