Quantum mechanics: To be or not to be local

  title={Quantum mechanics: To be or not to be local},
  author={Alain Aspect},
  • A. Aspect
  • Published 19 April 2007
  • Physics
  • Nature
The experimental violation of mathematical relations known as Bell's inequalities sounded the death-knell of Einstein's idea of 'local realism' in quantum mechanics. But which concept, locality or realism, is the problem? Most of us, most of the time, can get along in life and in science with a sturdy concept of what is 'real'. Generally speaking, an external reality exists independent of observation. But in the world of quantum physics, where individual events are predicted only in terms of… 

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