Conceptual problems in quantum mechanics

Decoherence is widely felt to have something to do with the quantum measurement problem, but getting clear on just what is made difficult by the fact that the ‘measurement problem’, as traditionally presented in foundational and philosophical discussions, has become somewhat disconnected from the conceptual problems posed by real physics. This, in turn, is because quantum mechanics as discussed in textbooks and in foundational discussions has become somewhat removed from scientific practice, especially where the analysis of measurement is concerned. This paper has two goals: firstly (§§1–2), to present an account of how quantum measurements are actually dealt with in modern physics (hint: it does not involve a collapse of the wave function) and to state the measurement problem from the perspective of that account; and secondly (§§3–4), to clarify what role decoherence plays in modern measurement theory and what effect it has on the various strategies that have been proposed to solve the measurement problem.

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Dirac, Von Neumann, and the Derivation of the Quantum Formalism

The Quantum Cookbook ◽

10.1093/oso/9780198827856.003.0011 ◽

2020 ◽

pp. 203-218

Author(s):

Jim Baggott

Keyword(s):

Hilbert Space ◽

Quantum Mechanics ◽

Critical Stage ◽

Von Neumann ◽

Quantum Formalism ◽

Conceptual Problems ◽

Underlying Reality

The evolution of quantum mechanics through the 1920s was profoundly messy. Some physicists believed that it was necessary to throw out much of the conceptual baggage that early quantum mechanics tended to carry around with it and re-establish the theory on much firmer ground. It was at this critical stage that the search for deeper insights into the underlying reality was set aside in favour of mathematical expediency. All the conceptual problems appeared to be coming from the wavefunctions. But whatever was to replace them needed to retain all the properties and relationships that had so far been discovered. Dirac and von Neumann chose to derive a new quantum formalism by replacing the wavefunctions with state vectors operating in an abstract Hilbert space, and formally embedding all the most important definitions and relations within a system of axioms.

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Conceptual problems in quantum mechanics

Soviet Physics Uspekhi ◽

10.1070/pu1992v035n10abeh002271 ◽

1992 ◽

Vol 35 (10) ◽

pp. 857-896 ◽

Cited By ~ 1

Author(s):

V P Demutskiĭ ◽

R V Polovin

Keyword(s):

Quantum Mechanics ◽

Conceptual Problems

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FUNDAMENTAL SPATIO-TEMPORAL DECOHERENCE: A KEY TO SOLVING THE CONCEPTUAL PROBLEMS OF BLACK HOLES, COSMOLOGY AND QUANTUM MECHANICS

International Journal of Modern Physics D ◽

10.1142/s0218271806009613 ◽

2006 ◽

Vol 15 (12) ◽

pp. 2181-2185 ◽

Cited By ~ 12

Author(s):

RODOLFO GAMBINI ◽

RAFAEL A. PORTO ◽

JORGE PULLIN

Keyword(s):

Black Holes ◽

Black Hole ◽

Quantum Mechanics ◽

Quantum Theory ◽

Measurement Problem ◽

Fundamental Level ◽

Black Hole Information ◽

Conceptual Problems ◽

Spatio Temporal ◽

Loss Of Coherence

Unitarity is a pillar of quantum theory. Nevertheless, it is also a source of several of its conceptual problems. We note that in a world where measurements are relational, as is the case in gravitation, quantum mechanics exhibits a fundamental level of loss of coherence. This can be the key to solving, among others, the puzzles posed by the black hole information paradox, the formation of inhomogeneities in cosmology and the measurement problem in quantum mechanics.

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- The Conceptual Problems of Quantum Mechanics

Quantum Mechanics ◽

10.1201/b19619-30 ◽

2015 ◽

pp. 392-429

Keyword(s):

Quantum Mechanics ◽

Conceptual Problems

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MEASUREMENT IN QUANTUM PHYSICS

International Journal of Modern Physics E ◽

10.1142/s0218301399000197 ◽

1999 ◽

Vol 08 (03) ◽

pp. 257-287 ◽

Cited By ~ 1

Author(s):

MICHAEL DANOS ◽

TIEN D. KIEU

Keyword(s):

Wave Function ◽

Quantum Mechanics ◽

Quantum Measurement ◽

Quantum Physics ◽

Quantum Fields ◽

Bell’S Inequalities ◽

Bell's Inequalities ◽

Conceptual Problems

The conceptual problems in quantum mechanics — related to the collapse of the wave function, the particle-wave duality, the meaning of measurement — arise from the need to ascribe particle character to the wave function. As will be shown, all these problems dissolve when working instead with quantum fields, which have both wave and particle character. Otherwise the predictions of quantum physics, including Bell's inequalities, coincide with those of the conventional treatments. The process of decoherence which governs the transfer of the results of the quantum measurement to the classical realm is also carefully discussed.

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