REVIEW
Quantum Mechanics without Nonlocality
Quantum Physics · Submitted 21 Feb 2006 · 27 references
Pith's verdict: The paper's central claim that Born's rule fails for entangled states rests on an extra postulate that makes a concrete wrong prediction (no interference in 1D scattering), so the nonlocality argument collapses.
T0 · AI review
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Referee report
The paper
The paper claims
This paper argues that quantum nonlocality is an artifact of misapplying Born's rule to entangled states.
The reading
What carries the argument
The central object is the decomposition $\psi_{full}(x;E)=\psi_{ref}(x;E)+\psi_{tr}(x;E)$ of the stationary scattering solution into reflected and transmitted parts, together with the trimmed packets $\tilde{\psi}_{ref}$ and $\tilde{\psi}_{tr}$ that belong to opposite sides of the barrier's midpoint. These packets obey the time-dependent Schrödinger equation everywhere except at the midpoint, where the continuity equation is still satisfied. They serve as the unentangled, 'non-dendritic' states for which observables are defined; the original full state, being their superposition, is called entangled and is declared inaccessible to one-particle observables. This decomposition is what lets the paper locate nonlocality in the misapplication of the superposition principle rather than in any actual faster-than-light influence.
Extended reading notes
Core claim
The central claim is that quantum nonlocality is not an actual phenomenon. In the paper's view, it appears in quantum mechanics because the superposition principle does not conceptually separate unentangled states from superpositions of macroscopically distinct alternatives. For a particle completing a one-dimensional scattering, the full wave function can be uniquely written as $\psi_{full}=\psi_{ref}+\psi_{tr}$, and the two parts can be trimmed into wave packets that describe the reflected and transmitted sub-processes separately. Since these sub-processes are macroscopically distinct at the final stage, the one-particle state is an entangled one, and a particle, being indivisible, cannot be in two such alternatives simultaneously. Hence no observable exists for the entangled state, Born's rule does not apply to it, and Bell inequalities—which require averaging over an entangled state—have no clear physical sense. Their observed violation is therefore not evidence of nonlocality but only evidence that the correlations in the existing theory conflict with special relativity.
Load-bearing premise
The load-bearing premise, asserted in Section 4, is that a particle is an indivisible object that cannot take part in two or more alternative macroscopically distinct sub-processes, so that no observable can be defined for an entangled state.
Editorial extensions
If this is right
- Bell inequality violation experiments no longer count as evidence for nonlocality; on this view they show only that the correlations used in standard entangled-state calculations are incompatible with special relativity.
- Born's rule should be restricted to unentangled time-dependent states; expectation values computed on an entangled state are physically meaningless.
- For one-particle scattering, the only meaningful time is the dwell time, measurable with a non-demolishing clock; group and other characteristic times for the entangled state have no physical sense.
- For compound systems, correlation calculations are legitimate only when both events lie on a single 'non-dendritic' multi-particle trajectory, i.e., only for unentangled states.
- The superposition principle must be revised to distinguish macroscopically distinct states from their superpositions and to force any entangled state into a decomposition into unentangled states.
Reading between the lines
- If the paper is right, entanglement-based technologies that treat Bell-inequality violation as a resource—such as device-independent randomness expansion or quantum key distribution—would be relying on averages that are not physically defined, so their security analysis would need a local reinterpretation.
- The argument leaves the notion 'macroscopically distinct' unquantified; a general criterion would be needed before the no-observables rule could be applied beyond the scattering example, so the paper's proposal is best read as a challenge to define such a boundary.
- A direct test of the model is to check numerically whether the trimmed wave packets remain good solutions of the Schrödinger equation away from the midpoint for realistic potentials; if the equation is appreciably violated, the decomposition cannot be physically legitimate.
- If accepted, the decomposition suggests that single-particle entanglement and multiparticle entanglement may need different treatments, since the indivisibility premise applies literally only to a single particle; extending the rule to compound systems is an extrapolation the paper makes but does not prove.
Original abstract
We argue that quantum nonlocality of entangled states is not an actual phenomenon. It appears in quantum mechanics as a consequence of the inconsistency of its superposition principle with the corpuscular properties of a quantum particle. In the existing form, this principle does not distinguish between macroscopically distinct states of a particle and their superpositions: it implies introducing observables for a particle, even if it is in an entangled state. However, a particle cannot take part simultaneously in two or more alternative macroscopically distinct sub-processes. Thus, calculating the expectation values of the one-particle's observables, for entangled states, is physically meaningless: Born's formula is not applicable to such states. The same concerns the entangled states of compound quantum systems. In the {\it existing} quantum mechanics, introducing Bell's inequalities is fully legal. However, these inequalities imply averaging over an entangled state, and, hence, they have no basis for their clear physical interpretation. Experiments to confirm the violation of Bell's inequalities do not prove the existence of nonlocality in microcosm. They confirm only that correlations introduced in the existing theory of entangled states have no physical sense, for they contradict special relativity.
The compiled record
The paper's own sentences, arranged, kept beside the review and separate from it. Each label is drawn from a closed vocabulary; the number beside it is the probability the classifier gave that label. Numbers in the tables are the authors', checked by code. No sentence in this record was written by a model.
The abstract, sentence by sentence
We argue that quantum nonlocality of entangled states is not an actual phenomenon. It appears in quantum mechanics as a consequence of the inconsistency of its superposition principle with the corpuscular properties of a quantum particle. In the existing form, this principle does not distinguish between macroscopically distinct states of a particle and their superpositions: it implies introducing observables for a particle, even if it is in an entangled state. However, a particle cannot take part simultaneously in two or more alternative macroscopically distinct sub-processes. Thus, calculating the expectation values of the one-particle's observables, for entangled states, is physically meaningless: Born's formula is not applicable to such states. The same concerns the entangled states of compound quantum systems. In the {\it existing} quantum mechanics, introducing Bell's inequalities is fully legal. However, these inequalities imply averaging over an entangled state, and, hence, they have no basis for their clear physical interpretation. Experiments to confirm the violation of Bell's inequalities do not prove the existence of nonlocality in microcosm. They confirm only that correlations introduced in the existing theory of entangled states have no physical sense, for they contradict special relativity.
background contribution method result interpretation main claim
| # | sentence | role | the authors' own work | states the main conclusion | strength |
|---|---|---|---|---|---|
| s0 | We argue that quantum nonlocality of entangled states is not an actual phenomenon. | contribution 0.48 | 0.53 | 0.95 | asserted 0.93 |
| s1 | It appears in quantum mechanics as a consequence of the inconsistency of its superposition principle with the corpuscular properties of a quantum particle. | interpretation 0.82 | 0.20 | 0.16 | asserted 0.87 |
| s2 | In the existing form, this principle does not distinguish between macroscopically distinct states of a particle and their superpositions: it implies introducing observables for a particle, even if it is in an entangled state. | background 0.62 | 0.07 | 0.05 | asserted 0.99 |
| s3 | However, a particle cannot take part simultaneously in two or more alternative macroscopically distinct sub-processes. | background 0.34 | 0.10 | 0.06 | asserted 1.00 |
| s4 | Thus, calculating the expectation values of the one-particle's observables, for entangled states, is physically meaningless: Born's formula is not applicable to such states. | interpretation 0.53 | 0.26 | 0.16 | asserted 1.00 |
| s5 | The same concerns the entangled states of compound quantum systems. | result 0.49 | 0.17 | 0.04 | asserted 0.99 |
| s6 | In the {\it existing} quantum mechanics, introducing Bell's inequalities is fully legal. | background 0.98 | 0.05 | 0.03 | asserted 1.00 |
| s7 | However, these inequalities imply averaging over an entangled state, and, hence, they have no basis for their clear physical interpretation. | interpretation 0.87 | 0.14 | 0.08 | asserted 1.00 |
| s8 | Experiments to confirm the violation of Bell's inequalities do not prove the existence of nonlocality in microcosm. | interpretation 0.93 | 0.07 | 0.27 | asserted 1.00 |
| s9 | They confirm only that correlations introduced in the existing theory of entangled states have no physical sense, for they contradict special relativity. | interpretation 0.98 | 0.10 | 0.26 | asserted 1.00 |
What was examined, and what was not
- arXiv listing abstract v3
- full text
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- references and citing sentences
- relations to other papers
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- R cross-paper relations
References
How the literature uses it
Papers whose main result relates to this one's
States the same result 2 papers
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Consequently, there is no nonlocal influence between entangled particles in measurements.
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Here I discuss an experiment involving particles entangled in energy and time variables that shows that there is no nonlocal state reduction during measurements on entangled particles.
An experiment that proves the absence of nonlocality in quantum mechanics · 0.93
States a conflicting result 1 paper
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We show that the observed phenomenon of quantum nonlocality cannot be incorporated in a class of $\psi$-epistemic models.
Bell Nonlocality and the Reality of Quantum Wavefunction · 0.92
Discussion
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