2002/04/30 by Hiroaki Terashima, Masahito Ueda
Physics and Astronomy · #quant-ph
published as Quantum Inf.Comput. 3 (2003) 224-228 · 7 pages, some discussions are omitted to shorten
arxiv created 2002/11/08 · arxiv updated 2009/12/01
Within the framework of relativistic quantum theory, we consider the Einstein-Podolsky-Rosen (EPR) gedanken-experiment in which measurements of the spin are performed by moving observers. We find that the perfect anti-correlation in the same direction between the EPR pair no longer holds in the observers' frame. This does not imply a breakdown of the non-local correlation. We explicitly show that the observers must measure the spin in appropriately chosen different directions in order to observe the perfect anti-correlation. This fact should be taken into account in utilizing the entangled state in quantum communication by moving observers.