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

  title={Reply to Comment on "Particle Path Through a Nested Mach-Zehnder Interferometer".},
  author={Robert B. Griffiths},
  journal={arXiv: Quantum Physics},
  • 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] 

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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

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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.

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.

Counterfactuality of ‘counterfactual

    communication. J. Phys. A,
  • 2015