Realism in Quantum Mechanics and a New Version of the EPR Experiment

  • Karl Popper
Part of the Fundamental Theories of Physics book series (FTPH, volume 10)


Since 1927, physicists with few exceptions (Einstein, Podolsky and Rosen; de Broglie; Landé) accepted the Copenhagen interpretation of the quantum formalism, due to Heisenberg, Bohr and Pauli. Since 1934 I opposed this. I contended that the quantum formalism in its statistical interpretation (Einstein, Born) had no special epistemological consequences; that it could, and should, be interpreted realistically (and, of course, locally); and that the so-called indeterminacy relations were just scatter relations; and that the so-called ‘collapse of the wave packet’ was something that occurred in any probabilistic theory and had nothing to do with Planck’s quantum h and even less with an action at a distance. I now submit a new variant of the EPR experiment that can decide between a realistic interpretation and Copenhagen.


Quantum Theory Wave Packet Hide Variable Quantum Formalism Copenhagen Interpretation 
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Copyright information

© Karl R. Popper 1985

Authors and Affiliations

  • Karl Popper
    • 1
  1. 1.London School of Economics & Political ScienceLondonUK

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