International Journal of Theoretical Physics

, Volume 51, Issue 6, pp 1783–1791 | Cite as

Nonlocal Appearance of a Macroscopic Angular Momentum

Article

Abstract

We discuss a type of measurement in which a macroscopically large angular momentum (spin) is “created” nonlocally by the measurement of just a few atoms from a double Fock state. This procedure apparently leads to a blatant nonconservation of a macroscopic variable—the local angular momentum. We argue that while this gedankenexperiment provides a striking illustration of several counter-intuitive features of quantum mechanics, it does not imply a non-local violation of the conservation of angular momentum.

Keywords

Nonlocality Quantum measurement Bose-Einstein condensate 

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Copyright information

© Springer Science+Business Media, LLC 2011

Authors and Affiliations

  1. 1.Institute for Quantum Optics and Quantum Information (IQOQI)Austrian Academy of SciencesViennaAustria
  2. 2.Low Temperature LaboratoryAalto UniversityAaltoFinland
  3. 3.Department of PhilosophyUniversity of ArizonaTucsonUSA

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