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Physical Review A

Galilean covariance of a reduced density matrix

Paweł Caban, Kordian A. Smoliński, Zbigniew Walczak

Published Oct 21, 2003• 3 citations
Publisher

Abstract

We consider a system of two spin-s particles. We show that the reduced density matrix of this system obtained by tracing out over momentum is invariant under Galilean boosts and translations, and covariant under rotations. It implies that the spin entanglement of the system is the same for all Galilean observers.
DOI
10.1103/physreva.68.044101

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