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arXiv · 1502.01080

Lorentz transformations for massive two-particle systems: entanglement change and invariant subspaces

Esteban Castro-Ruiz·Eduardo Nahmad-Achar
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Abstract

Lorentz boosts on particles with spin and momentum degrees of freedom induce momentum-dependent rotations. Since, in general, different particles have different momenta, the transformation on the whole state is not a representation of the rotation group. Here we identify the group that acts on a two-particle system and, for the case when the momenta of the particles are correlated, find invariant subspaces that have interesting properties for quantum information processes in relativistic scenarios. A basis of states is proposed for the study of transformations of spin states under Lorentz boosts, which is a good candidate for building quantum communication protocols in relativistic scenarios.

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Esteban Castro-Ruiz, Eduardo Nahmad-Achar. 2015-02-04. Lorentz transformations for massive two-particle systems: entanglement change and invariant subspaces. https://doi.org/10.1088/0031-8949%2F90%2F6%2F068018

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