Realism and the Physical World

  • A. J. LeggettEmail author


I consider the extent to which the applicability of the concept of classical realism is constrained, irrespective of the validity or not of the quantum formalism, by existing experiments both in the EPR-Bell setup, including recent experiments testing “nonlocal realistic” theories, and in the area of “macroscopic quantum coherence”. Unless we are willing to sacrifice one or more other intuitively plausible notions such as the conventional “arrow of time”, it appears impossible, in either context, to maintain the classical notion of realism. [Editors note: For a video of the talk given by Prof. Leggett at the Aharonov-80 conference in 2012 at Chapman University, see]


Quantum Mechanic Polarizer Setting Macroscopic Object Quantum Superposition Past Light Cone 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



This work was supported in part by the National Science Foundation through grant no. NSF-EIA-03-50842.


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Copyright information

© Springer-Verlag Italia 2014

Authors and Affiliations

  1. 1.Department of PhysicsNational University of SingaporeSingaporeSingapore
  2. 2.University of Illinois at Urbana-ChampaignUrbanaUSA

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