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Entanglement is Schrödinger’s name for superposition in a multi-particle system. In particular he called entangled states two-particle states that cannot be factored into products of two single-particle states in any representation. Multi-particle superposition is considered to be the characteristic trait of quantum mechanics [1]. If one cannot distinguish (even in principle) between different paths from source to detector, the amplitudes for these alternative paths add coherently, and multi-particle correlations appear. If it is possible in principle to distinguish, correlations vanish. Work by John Bell [2], by Daniel M. Greenberger, Michel A. Horne, and Anton Zeilinger [3], and by Lucien Hardy [4] pointed out that local-realistic theories cannot account for the twoand multiparticle correlations implied by the superposition principle. Local-realism is the name for Einstein’s assumption that nothing in physical reality happens fasten than light. The quantum mechanical violation of local-realism is now mostly called nonlocality. In spite of the loopholes in the experiments [5], it is today largely accepted that superluminal nonlocality is a feature of nature: most physicists will not