Weak values and the past of a quantum particle

• URL: http://arxiv.org/abs/2109.14060v5
• Date: Sun, 23 Apr 2023 05:03:07 GMT
• Title: Weak values and the past of a quantum particle
• Authors: Jonte R. Hance, John Rarity, and James Ladyman
• Abstract summary: We investigate four key issues with using a nonzero weak value of the spatial projection operator to infer the past path of a quantum particle. We note that weak measurements disturb a system, so any approach relying on such a perturbation to determine the location of a quantum particle describes the state of a disturbed system. We know of no experiment with testable consequences that demonstrates a connection between particle presence and weak values.
• Score: 0.0
• License: http://creativecommons.org/licenses/by/4.0/
• Abstract: 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 disturb a system, so any approach relying on such a perturbation to determine the location of a quantum particle describes the state of a disturbed system, not that of a hypothetical undisturbed system. Secondly, even assuming no disturbance, there is no reason to associate the non-zero weak value of an operator containing the spatial projection operator with the classical idea of `particle presence'. Thirdly, weak values are only measurable over ensembles, and so to infer properties of individual particles from values of them is problematic. Finally, weak value approaches to the path of a particle do not provide information beyond standard quantum mechanics (and the classical modes supporting the experiment). We know of no experiment with testable consequences that demonstrates a connection between particle presence and weak values.

Related papers

• Quantum Discord Witness with Uncharacterized Devices [18.751513188036334]
  We propose a new approach using uncharacterized measurements to witness quantum discord of an unknown bipartite state within arbitrary dimension system. The feature of high robustness against device imperfections, such as loss-tolerance and error-tolerance, shows our method is experimentally feasible.
  arXiv  Detail & Related papers  (2023-03-20T14:51:53Z)
• Experimental demonstration of separating the waveparticle duality of a single photon with the quantum Cheshire cat [18.728749435511805]
  We experimentally separated the wave and particle attributes of a single photon by exploiting the quantum Cheshire cat concept. By applying a weak disturbance to the evolution of the system, we achieve an effect similar to the quantum Cheshire cat.
  arXiv  Detail & Related papers  (2023-03-09T11:35:01Z)
• Comment on "Does the weak trace show the past of a quantum particle?" [0.0]
  We argue that null weak values of the spatial projectors are inadequate to infer the presence of a quantum particle at an intermediate time between preparation and detection. This conclusion relies on two arguments - (i) the role of the disturbance induced by a weak measurement, and (ii) classical-like features like continuous paths that must purportedly be associated with a quantum particle presence.
  arXiv  Detail & Related papers  (2022-02-23T15:47:03Z)
• Quantum reality with negative-mass particles [0.0]
  Physical interpretations of the time-symmetric formulation of quantum mechanics are discussed in terms of weak values. A top-down ontological model is introduced that treats the weak values of observables as physically real during the time between pre- and post-selection.
  arXiv  Detail & Related papers  (2022-01-24T08:09:35Z)
• Enhanced nonlinear quantum metrology with weakly coupled solitons and particle losses [58.720142291102135]
  We offer an interferometric procedure for phase parameters estimation at the Heisenberg (up to 1/N) and super-Heisenberg scaling levels. The heart of our setup is the novel soliton Josephson Junction (SJJ) system providing the formation of the quantum probe. We illustrate that such states are close to the optimal ones even with moderate losses.
  arXiv  Detail & Related papers  (2021-08-07T09:29:23Z)
• Quantum uncertainty as classical uncertainty of real-deterministic variables constructed from complex weak values and a global random variable [0.0]
  We construct a class of real-deterministic c-valued variables out of the weak values obtained via a non-perturbing weak measurement of quantum operators. We show that this class of c-valued physical quantities'' provides a real-deterministic contextual hidden variable model for the quantum expectation value of a certain class of operators.
  arXiv  Detail & Related papers  (2021-06-21T22:43:26Z)
• Non-equilibrium stationary states of quantum non-Hermitian lattice models [68.8204255655161]
  We show how generic non-Hermitian tight-binding lattice models can be realized in an unconditional, quantum-mechanically consistent manner. We focus on the quantum steady states of such models for both fermionic and bosonic systems.
  arXiv  Detail & Related papers  (2021-03-02T18:56:44Z)
• Mesoscopic quantum superposition states of weakly-coupled matter-wave solitons [58.720142291102135]
  We establish quantum features of an atomic soliton Josephson junction (SJJ) device. We show that the SJJ-model in quantum domain exhibits unusual features due to its effective nonlinear strength proportional to the square of total particle number. We have shown that the obtained quantum state is more resistant to few particle losses from the condensates if tiny components of entangled Fock states are present.
  arXiv  Detail & Related papers  (2020-11-26T09:26:19Z)
• Weak measurements, non-classicality and negative probability [0.0]
  It has been shown that nonexistence of a classical joint probability scheme gives rise to sufficiency conditions for nonlocality. The crux of the paper is that the pseudo-probabilities, which can take negative values, can be directly measured as anomalous weak values.
  arXiv  Detail & Related papers  (2020-06-22T17:08:05Z)
• Weak values from path integrals [0.0]
  We show how Feynman propagators can in principle be experimentally inferred from weak value measurements. We obtain expressions for weak values parsing unambiguously the quantum and the classical aspects of weak couplings between a system and a probe.
  arXiv  Detail & Related papers  (2020-02-03T15:45:15Z)
• Einselection from incompatible decoherence channels [62.997667081978825]
  We analyze an open quantum dynamics inspired by CQED experiments with two non-commuting Lindblad operators. We show that Fock states remain the most robust states to decoherence up to a critical coupling.
  arXiv  Detail & Related papers  (2020-01-29T14:15:19Z)

This list is automatically generated from the titles and abstracts of the papers in this site.

This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.