Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Zeitschrift für Naturforschung A

Surrealistic Bohm Trajectories

Berthold‐Georg Englert, Marian O. Scully, Georg Süssmann, HERBERT WALTHER

Published Dec 1, 1992• 237 citations
Publisher

Abstract

Abstract A study of interferometers with one-bit which-way detectors demonstrates that the trajectories, which David Bohm invented in his attempt at a realistic interpretation of quantum mechanics, are in fact surrealistic, because they may be macroscopically at variance with the observed track of the particle. We consider a two-slit interferometer and an incomplete Stern-Gerlach interferometer, and propose an experimentum crucis based on the latter.

DOI
10.1515/zna-1992-1201

Related papers

What is Surrealistic about Bohm Trajectories?

Marcelo Terra Cunha

We discuss interferometers in Bohmian quantum mechanics. It is shown that, with the correct configuration space, Bohm trajectories in a which way interferometer are not surrealistic, but behaves exactly as common sense suggests. Some remarks about a way to generalize Bohmian mechanics to treat density matrix are also made. PACS: 03.65.Bz, 03.75.Dg Key words: Bohm Trajectories, Which Way Interferometers, ESSW

arXiv:quant-ph/9809006•Sep 3, 1998•1 citation

What is Surrealistic about Bohm Trajectories

Marcelo Terra Cunha

We discuss interferometers in Bohmian quantum mechanics. It is shown that, with the correct configuration space, Bohm trajectories in a which way interferometer are not surrealistic, but behaves exactly as common sense suggests. Some remarks about a way to generalize Bohmian mechanics to treat density matrix are also made. PACS: 03.65.Bz, 03.75.Dg Key words: Bohm Trajectories, Which Way Interferometers, ESSW

Physics Letters A•Sep 7, 1998•0 citations

What is Surrealistic about Bohm Trajectories

Terra Cunha

We discuss interferometers in Bohmian quantum mechanics. It is shown that, with the correct configuration space, Bohm trajectories in a which way interferometer are not surrealistic, but behaves exactly as common sense suggests. Some remarks about a way to generalize Bohmian mechanics to treat density matrix are also made. PACS: 03.65.Bz, 03.75.Dg Key words: Bohm Trajectories, Which Way Interferometers, ESSW

•Sep 3, 1998•3 citations

Quantum Trajectories: Real or Surreal?

Basil J. Hiley, Peter Van Reeth

The claim of Kocsis et al. to have experimentally determined "photon trajectories" calls for a re-examination of the meaning of "quantum trajectories". We will review the arguments that have been assumed to have established that a trajectory has no meaning in the context of quantum mechanics. We show that the conclusion that the Bohm trajectories should be called "surreal" because they are at "variance with the actual observed track" of a particle is wrong as it is based on a false argument. We also present the results of a numerical investigation of a double Stern-Gerlach experiment which shows clearly the role of the spin within the Bohm formalism and discuss situations where the appearance of the quantum potential is open to direct experimental exploration.

Entropy•May 8, 2018•18 citations

Reply to Comment on "Surrealistic Bohm Trajectories"

Berthold‐Georg Englert, Marlan O. Scully, Georg Süssmann +1 more

Let us begin with a response to the summary of the Comment by D. Durr, W. Fusseder, S. Goldstein, and N. Zanghi [1]. We are accused to not stay inside orthodox quantum but to employ a naive, largely incoherent operationalism instead. We think that this charge is not justified, because we did apply standard quantum theory correctly and also followed the rules of Bohmian Mechanics (BM) carefully. In the following we react to the more essential points of the Comment in some detail. The Comment suggests that we have conceded many virtues to BM and that we have admitted that standard quantum theory is plagued by notorious conceptual difficulties. This is not the case. On the contrary, we maintain that BM is not needed to have the Schrodinger equation embedded into a physical theory. Standard quantum theory has already clarified the significance of Schrodinger's wave function as a tool used by theoreticians to arrive at probabalistic predictions. It is quite unnecessary, and indeed dangerous, to attribute any additional meaning to the (/^-function. The semantic difference between inconsistent and surrealistic is not the issue. It is the purpose of our paper to show clearly that the interpretation of the Bohm trajectory as the real retrodicted history of the atom observed on the screen is implausible, because this trajectory can be macroscopically at variance with the detected, actual way through the interferometer. And yes, we do have a framework to talk about path detection; it is based upon the local interaction of

Zeitschrift für Naturforschung A•Dec 1, 1993•24 citations

Comment on "Observing the Average Trajectories of Single Photons in a Two-Slit Interferometer"

Timothy M. Coffey, Róbert E. Wyatt

Kocsis et al. (Science, Reports 3 June 2011, p. 1170) state that the experimentally deduced average photon trajectories are identical to the particle trajectories of Bohm's quantum mechanics. No supporting evidence, however, was provided. The photon trajectories presented in their report do not converge to high probability regions, a familiar and necessary behavior of Bohm trajectories. We reanalyze their data and calculations, conclude that the average photon trajectories do indeed agree with Bohm, and discuss possible interpretations of this result.

arXiv:1109.4436•Sep 20, 2011•0 citations
Abstract A study of interferometers with one-bit which-way detectors demonstrates that the trajectories, which David Bohm invented in his attempt at a realistic interpretation of quantum mechanics, are in fact surrealistic, because they may be macroscopically at variance with the observed track of the particle. We consider a two-slit interferometer and an incomplete Stern-Gerlach interferometer, and propose an experimentum crucis based on the latter.
The claim of Kocsis et al. to have experimentally determined "photon trajectories" calls for a re-examination of the meaning of "quantum trajectories". We will review the arguments that have been assumed to have established that a trajectory has no meaning in the context of quantum mechanics. We show that the conclusion that the Bohm trajectories should be called "surreal" because they are at "variance with the actual observed track" of a particle is wrong as it is based on a false argument. We also present the results of a numerical investigation of a double Stern-Gerlach experiment which shows clearly the role of the spin within the Bohm formalism and discuss situations where the appearance of the quantum potential is open to direct experimental exploration.
Let us begin with a response to the summary of the Comment by D. Durr, W. Fusseder, S. Goldstein, and N. Zanghi [1]. We are accused to not stay inside orthodox quantum but to employ a naive, largely incoherent operationalism instead. We think that this charge is not justified, because we did apply standard quantum theory correctly and also followed the rules of Bohmian Mechanics (BM) carefully. In the following we react to the more essential points of the Comment in some detail. The Comment suggests that we have conceded many virtues to BM and that we have admitted that standard quantum theory is plagued by notorious conceptual difficulties. This is not the case. On the contrary, we maintain that BM is not needed to have the Schrodinger equation embedded into a physical theory. Standard quantum theory has already clarified the significance of Schrodinger's wave function as a tool used by theoreticians to arrive at probabalistic predictions. It is quite unnecessary, and indeed dangerous, to attribute any additional meaning to the (/^-function. The semantic difference between inconsistent and surrealistic is not the issue. It is the purpose of our paper to show clearly that the interpretation of the Bohm trajectory as the real retrodicted history of the atom observed on the screen is implausible, because this trajectory can be macroscopically at variance with the detected, actual way through the interferometer. And yes, we do have a framework to talk about path detection; it is based upon the local interaction of
Kocsis et al. (Science, Reports 3 June 2011, p. 1170) state that the experimentally deduced average photon trajectories are identical to the particle trajectories of Bohm's quantum mechanics. No supporting evidence, however, was provided. The photon trajectories presented in their report do not converge to high probability regions, a familiar and necessary behavior of Bohm trajectories. We reanalyze their data and calculations, conclude that the average photon trajectories do indeed agree with Bohm, and discuss possible interpretations of this result.