Input interpretation:

EPR paradox (physical principle)


The apparent paradox that arises when two quantum systems interact in such a way as to link both their spatial coordinates in a certain direction and their linear momenta in the same direction. As a result of this "entanglement," determining either position or momentum for one system would fix (respectively) the position or the momentum of the other, arguing that one cannot maintain both an intuitive condition of local action and the completeness of the quantum description by means of the wavefunction.

Alternate name:

Einstein-Podolsky-Rosen paradox


formulation date | 1935 (82 years ago)\nformulators | Albert Einstein  |  Boris Podolsky  |  Nathan Rosen\nadditional people involved | Alain Aspect  |  John Stewart Bell

Current evidence:

In 1964, John Bell showed that quantum mechanics and Einstein\'s assumptions lead to different results (by a factor of 3\/2 for certain correlations).\nMany Bell test experiments (e.g., those of Alain Aspect and others) all show that pure quantum mechanics, and not Einstein\'s "local realism" describe the physical world.\nMost physicists today believe that quantum mechanics is correct and that the EPR paradox is a "paradox" only because classical intuition does not correspond to physical reality.


physical paradoxes