Quantum stochastic phase-space theorems lead to hidden causal loops in a model for measurement consistent with macroscopic realism, Bell nonlocality and no-signaling

• URL: http://arxiv.org/abs/2205.06070v4
• Date: Sat, 30 Nov 2024 00:24:59 GMT
• Title: Quantum stochastic phase-space theorems lead to hidden causal loops in a model for measurement consistent with macroscopic realism, Bell nonlocality and no-signaling
• Authors: M D Reid, P D Drummond,
• Abstract summary: We show how quantum measurement and nonlocality can be explained consistently with macroscopic realism and no-signaling. We analyze a measurement of $hatx$ on a system prepared in a superposition of eigenstates.
• Score: 0.0
• License:
• Abstract: In this paper, we show how quantum measurement and nonlocality can be explained consistently with macroscopic realism and no-signaling. We analyze a measurement of $\hat{x}$ on a system prepared in a superposition of eigenstates, with measurement modeled as amplification, realized by interacting the system with an amplifier. Deriving quantum stochastic path-integral theorems, we prove an equivalence between a phase-space probability distribution $Q(x,p)$ (which uniquely represents the quantum state) and stochastic trajectories for the amplified and attenuated variables, $x$ and $p$, that propagate backwards and forwards in time, respectively. For the superposition, but not the mixture, the backward and forward-propagating trajectories are connected by the initial-time conditional distribution $Q(p|x)$, leading to a causal loop. The joint densities for $x(t)$ and $p(t)$ yield $Q(x,p,t)$, confirming causal consistency. A feature is hidden noise associated with an eigenstate. Unlike the eigenvalue, this noise is not amplified. This motivates an ontological model for measurement, where the amplified amplitude x(t) gives the detected outcome, from which Born's rule follows. For macroscopic superpositions, we demonstrate consistency with macroscopic realism: Further, we evaluate the initial-time distribution $Q_{loop}(x,p)$ for the coupled trajectories conditioned on a given outcome, showing that this cannot correspond to a quantum state. Finally, we analyze Einstein-Podolsky-Rosen and Bell nonlocality. Our conclusion is a model for the collapse of the wave-function and nonlocality, consistent with three weak local realistic premises. We deduce a hybrid causal structure involving causal relations for amplified variables, demonstrating through explicit simulation how microscopic retrocausality can explain measurement and entanglement, without leading to retrocausality at a macroscopic level.

Related papers

• Resolving Schrödinger's analysis of the Einstein-Podolsky-Rosen paradox: an incompleteness criterion and weak elements of reality [0.0]
  The Einstein-Podolsky-Rosen (EPR) paradox was presented as an argument that quantum mechanics is an incomplete description of physical reality. Schrodinger pointed out that the correlated states of the paradox enable the simultaneous measurement of $hatx$ and $hatp$. We derive a criterion for the incompleteness of quantum mechanics, showing that the criterion is feasible for current experiments.
  arXiv  Detail & Related papers  (2024-11-30T09:18:45Z)
• Dynamically emergent correlations in bosons via quantum resetting [0.0]
  We study the nonequilibrium stationary state (NESS) induced by quantum resetting of a system of $N$ noninteracting bosons in a harmonic trap. We fully characterize the steady state by analytically computing several physical observables such as the average density, extreme value statistics, order and gap statistics. This is a rare example of a strongly correlated quantum many-body NESS where various observables can be exactly computed.
  arXiv  Detail & Related papers  (2024-07-29T18:00:35Z)
• Teaching ideal quantum measurement, from dynamics to interpretation [0.0]
  Ideal measurements are analyzed as processes of interaction between the tested system S and an apparatus A. Conservation laws are shown to entail two independent relaxation mechanisms. Born's rule then arises from the conservation law for the tested observable.
  arXiv  Detail & Related papers  (2024-05-29T22:36:06Z)
• Projected state ensemble of a generic model of many-body quantum chaos [0.0]
  The projected ensemble is based on the study of the quantum state of a subsystem $A$ conditioned on projective measurements in its complement. Recent studies have observed that a more refined measure of the thermalization of a chaotic quantum system can be defined on the basis of convergence of the projected ensemble to a quantum state design.
  arXiv  Detail & Related papers  (2024-02-26T19:00:00Z)
• Reinterpreting causal discovery as the task of predicting unobserved joint statistics [15.088547731564782]
  We argue that causal discovery can help inferring properties of the unobserved joint distributions' We define a learning scenario where the input is a subset of variables and the label is some statistical property of that subset.
  arXiv  Detail & Related papers  (2023-05-11T15:30:54Z)
• On counterfactual inference with unobserved confounding [36.18241676876348]
  Given an observational study with $n$ independent but heterogeneous units, our goal is to learn the counterfactual distribution for each unit. We introduce a convex objective that pools all $n$ samples to jointly learn all $n$ parameter vectors. We derive sufficient conditions for compactly supported distributions to satisfy the logarithmic Sobolev inequality.
  arXiv  Detail & Related papers  (2022-11-14T04:14:37Z)
• Geometric relative entropies and barycentric Rényi divergences [16.385815610837167]
  monotone quantum relative entropies define monotone R'enyi quantities whenever $P$ is a probability measure. We show that monotone quantum relative entropies define monotone R'enyi quantities whenever $P$ is a probability measure.
  arXiv  Detail & Related papers  (2022-07-28T17:58:59Z)
• Random quantum circuits transform local noise into global white noise [118.18170052022323]
  We study the distribution over measurement outcomes of noisy random quantum circuits in the low-fidelity regime. For local noise that is sufficiently weak and unital, correlations (measured by the linear cross-entropy benchmark) between the output distribution $p_textnoisy$ of a generic noisy circuit instance shrink exponentially. If the noise is incoherent, the output distribution approaches the uniform distribution $p_textunif$ at precisely the same rate.
  arXiv  Detail & Related papers  (2021-11-29T19:26:28Z)
• Graph-Theoretic Framework for Self-Testing in Bell Scenarios [37.067444579637076]
  Quantum self-testing is the task of certifying quantum states and measurements using the output statistics solely. We present a new approach for quantum self-testing in Bell non-locality scenarios.
  arXiv  Detail & Related papers  (2021-04-27T08:15:01Z)
• Generative Ensemble Regression: Learning Particle Dynamics from Observations of Ensembles with Physics-Informed Deep Generative Models [27.623119767592385]
  We propose a new method for inferring the governing ordinary differential equations (SODEs) by observing particle ensembles at discrete and sparse time instants. Particle coordinates at a single time instant, possibly noisy or truncated, are recorded in each snapshot but are unpaired across the snapshots. By training a physics-informed generative model that generates "fake" sample paths, we aim to fit the observed particle ensemble distributions with a curve in the probability measure space.
  arXiv  Detail & Related papers  (2020-08-05T03:06:40Z)
• Measurement-induced entanglement transitions in many-body localized systems [0.0]
  We investigate measurement-induced entanglement transitions in a system where the underlying unitary dynamics are many-body localized (MBL) This work further demonstrates how the nature of the measurement-induced entanglement transition depends on the scrambling nature of the underlying unitary dynamics. This leads to further questions on the control and simulation of entangled quantum states by measurements in open quantum systems.
  arXiv  Detail & Related papers  (2020-05-27T19:26:12Z)

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.