Historical Considerations on the Conceptual Experiment by Einstein, Podolsky and Rosen

David Böhm

Gino Tarozzi, Alwyn van der Merwe

The Italian Debate on Quantum Paradoxes.- 1. The Epistemological Roots of Quantum Paradoxes.- Waves, Particles and Complementarity.- Chance: Chaos or Logic?.- Some Critical Considerations on the Present Epistemological and Scientific Debate on Quantum Mechanics.- 2. Einstein Locauty, Separable Reality, and Quantum Correlations.- Physical Consequences of Reality Criteria for Quantum Phenomena.- Possible Link Between EPR Paradox and Waves.- A Criticism of Some Recently Proposed Models that Violate the Bell Inequality.- A Phenomenological Analysis of the EPR Argument.- 3. Causal and Deterministic Interpretations of Quantum Formausm.- Causal versus Orthodox Interpretation of Quantum Mechanics.- Perspectives of Physical Determinism.- Determinism, Separability, and Quantum Mechanics.- 4. Quantum Theory and Gravitation.- Can Singularities and Multidimensional Spaces Influence the Evolution of Quantum Mechanical Systems?.- Subquantum Mechanics and Graviton Blas.- 5. Logic and Probability in Quantum Mechanics.- Foundations of Quantum Mechanics. A Quantum Probabilistic Approach.- On the Adequacy of a Nonclassical Logic for Quantum Theory.- Remarks on the Hypothesis of Hidden Variables.- 6. Historical Developments of the Einstein-Bohr Controversy.- Historical Considerations on the Conceptual Experiment by Einstein, Podolsky and Rosen.- Continuity and Discontinuity: The Einstein-Bohr Conflict of Ideas and the Bohr-Fock Discussion.- How Italian Philosophy Reacted to the Advent of Quantum Mechanics in the Thirties.- Italian Studies in the Foundations of Quantum Physics. A Bibliography (1965-1985).

D. F. Orsini, L. R. N. Oliveira, M. G. E. da Luz

From a phenomenological and experimental viewpoint, quantum mechanics is remarkably successful in explaining effects and processes in the microscopic world. Recently, however, a growing body of literature has revisited the theory's own formal foundations, specifically addressing issues of self-consistency and completeness. As a major historical example of these foundational challenges, the Einstein-Podolsky-Rosen (EPR) argument famously claimed that the theory is incomplete. While many valid criticisms and refutations of the EPR logic exist, they generally rely on a combination of technical results and conceptual objections to EPR's interpretive assumptions, thus transcending the plain quantum framework itself. Motivated by these trends of examining the theory's structural limits, here we revisit the EPR argument. Focusing on elements essential to the EPR reasoning, we first analyze general quantum correlations for EPR states: (i) the fact that their observables are always associated with non-commuting operators, and (ii) the nature of the correlated information obtained through measurement. From these two points alone, and relying strictly on the core rules of quantum mechanics, we demonstrate how to overturn the alleged EPR incompleteness without invoking any extraneous propositions. Consequently, we show that the standard formalism alone suffices to resolve such type of skepticism regarding the theory's physical reach. This offers, at least in a paradigmatic instance, a powerful indication of a structurally well-founded, self-consistent quantum theory.

Diederik Aerts

Bernard d’Espagnat

The difference between the conceptual framework of classical physics and that of quantum physics which is due to the nonseparability property of the latter theory is better understood in specific examples. This chapter uses some specific examples to test the validity, both in classical and in quantum mechanics, of two conceptual principles. First is Reality Principle . The very concept of a reality may be criticized by philosophically minded empiricists. A widespread opinion, however, is that somehow a physical reality does exist, which should not just amount to the talks we give about it. In their search for a criterion that would make it possible to recognize elements of reality, A. Einstein, B. Podolsky, and N. Rosen had to take such considerations into account. Second, Principle of the Separability of Mechanically Isolated Systems, one can easily guess that this second principle, which remains somewhat implicit in the work of Einstein and his colleagues may well be the source of insuperable difficulties.

Asher Peres, Paul Singer