Reply to Comment on "Particle Path Through a Nested Mach-Zehnder Interferometer".

@article{Griffiths2017ReplyTC,
  title={Reply to Comment on "Particle Path Through a Nested Mach-Zehnder Interferometer".},
  author={Robert B. Griffiths},
  journal={arXiv: Quantum Physics},
  year={2017}
}
  • R. Griffiths
  • Published 5 December 2017
  • Physics
  • arXiv: Quantum Physics
While much of the technical analysis in the preceding Comment [1] is correct, in the end it confirms the conclusion reached in my previous work [2]: a consistent histories analysis provides no support for the claim of counterfactual quantum communication put forward in [3] 
View PDF on arXiv
16 Citations
Background Citations
2
Results Citations
2

16 Citations

When Photons Are Lying about Where They Have Been

The history of photons in a nested Mach–Zehnder interferometer with an inserted Dove prism with Bohmian trajectory of the photon is analyzed and it is argued that the Dove prism does not change the past of the photons.

Do weak values show the past of a quantum particle?

We investigate the use of weak values to determine the presence of an individual quantum particle. Specifically, we show issues with both Vaidman’s weak trace approach, and other approaches where a…

From a Quantum Paradox to Provably Counterfactual Disembodied Transport: Counterportation

We uncover a new quantum paradox, where a simple question about two identical systems of nested interferometers reveals surprising answers on the whereabouts of a photon, when considering weak…

Do the laws of physics prohibit counterfactual communication?

This paper proposes exactly such a counterfactual scheme where, unambiguously, none of Alice's photons that make it has been to Bob, and demonstrates counterfactuality experimentally by means of weak measurements, as well as conceptually using consistent histories.

Does the weak trace show the past of a quantum particle?

We investigate the weak trace approach to determining the path of a quantum particle. Specifically, obtaining the weak value of the position operator necessarily perturbs the system away from the…

Past of a particle in an entangled state

Vaidman has proposed a controversial criterion for determining the past of a single quantum particle based on the "weak trace" it leaves. We here consider more general examples of entangled systems…

From a Quantum Paradox to Counterportation

We uncover a new quantum paradox, where a simple question about two identical quantum systems reveals unsettlingly paradoxical answers when weak measurements are considered. Our resolution of the…

Weak values and the past of a quantum particle

We investigate four key issues with using a nonzero weak value of the spatial projection operator to infer the past path of an individual quantum particle. First, we note that weak measurements…

From counterportation to local wormholes

    Hatim Salih
    Computer Science
    Quantum Science and Technology
  • 2022
An experimental realisation of the protocol for the counterfactual disembodied transport of an unknown qubit where sender and receiver, remarkably, exchange no particles is proposed, and cavity quantum electrodynamics is employed, estimating resources for beating the classical fidelity limit.

How Quantum is Quantum Counterfactual Communication?

Quantum Counterfactual Communication is the recently-proposed idea of using quantum physics to send messages between two parties, without any matter/energy transfer associated with the bits sent.…

12 References

Comment on "Particle Path Through a Nested Mach-Zehnder Interferometer"

In a recent paper, arXiv:1604.04596, Griffiths questioned - based on an informative consistent-histories (CH) argument - the counterfactuality, for one of the bit choices, of Salih et al.'s protocol…

Particle Path Through a Nested Mach-Zehnder Interferometer

Possible paths of a photon passing through a nested Mach-Zehnder interferometer on its way to a detector are analyzed using the consistent histories formulation of quantum mechanics, and confirmed…

Comment on "Direct counterfactual transmission of a quantum state"

The protocol for counterfactual transmission of a qubit [Li et al., Phys. Rev. A 92, 052315 (2015)] relies on the counterfactuality of transmissions of bit 1 and of bit 0. Since counterfactuality of…

Protocol for direct counterfactual quantum communication.

Using the "chained" quantum Zeno effect, this work shows how, in the ideal asymptotic limit, information can be transferred between Alice and Bob without any physical particles traveling between them.

Comment on “Protocol for Direct Counterfactual Quantum Communication”

I argue that recent "Protocol for Direct Counterfactual Quantum Communication" by Salih et al. [PRL 110, 170502 (2013), arXiv:1206.2042] is counterfactual only for one type of the information bit.

Counterfactuality of ‘counterfactual’ communication

The counterfactuality of the recently proposed protocols for direct quantum communication is analyzed. It is argued that the protocols can be counterfactual only for one value of the transmitted bit.…

On the Consistent Histories Approach to Quantum Mechanics

We review the consistent histories formulations of quantum mechanics developed by Griffiths, Omnès and Gell-Mann and Hartle, and describe the classification of consistent sets. We illustrate some…

Consistent Quantum Theory

1. Introduction 2. Wave functions 3. Linear algebra in Dirac notation 4. Physical properties 5. Probabilities and physical variables 6. Composite systems and tensor products 7. Unitary dynamics 8.…

Direct counterfactual transmission of a quantum state

Counterfactuality of ‘counterfactual

    communication. J. Phys. A,
  • 2015