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Related papers: Quantum Measurements Constrained by Symmetries

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We show that the quantum description of measurement based on decoherence fixes the bug in quantum theory discussed in [D. Frauchiger and R. Renner, {\em Quantum theory cannot consistently describe the use of itself}, Nat. Comm. {\bf 9},…

Quantum Physics · Physics 2018-10-17 Armando Relaño

Wigner-friend scenarios -- in which external agents describe a closed laboratory containing a friend making a measurement -- highlight the difficulties inherent to quantum theory when accounting for measurements. In non-relativistic…

Quantum Physics · Physics 2024-09-13 J. Allam , A. Matzkin

Measurement quantum mechanics, the theory of a quantum system which undergoes a measurement process, is introduced by a loop of mathematical equivalencies connecting previously proposed approaches. The unique phenomenological parameter of…

Condensed Matter · Physics 2009-10-28 Carlo Presilla , Roberto Onofrio , Ubaldo Tambini

The measurement process in quantum mechanics is usually described by the von Neumann projection postulate, which forms a basic constituent of the laws of quantum mechanics. Since this postulate requires the outside observer of the system,…

Quantum Physics · Physics 2009-11-11 Masahiro Morikawa , Akika Nakamichi

The theory of measurement is employed to elucidate the physical basis of general relativity. For measurements involving phenomena with intrinsic length or time scales, such scales must in general be negligible compared to the (translational…

General Relativity and Quantum Cosmology · Physics 2015-06-25 Bahram Mashhoon

Uncertainty principle is the basis of quantum mechanics. It reflects the basic law of the movement of microscopic particles. Wigner-Yanase skew information, as a measure of quantum uncertainties, is used to characterize the intrinsic…

Quantum Physics · Physics 2021-05-11 Limei Zhang , Ting Gao , Fengli Yan

Precise measurements of both the arrival time and carrier frequency of light pulses are essential for time-frequency-encoded quantum technologies. Quantum mechanics, however, imposes fundamental limits on the simultaneous determination of…

This paper develops an agent-centric account of measurement that treats the preferred-basis problem is fundamentally perspectival. On this view, the system--apparatus--environment decomposition and the observables that are apt to become…

Quantum Physics · Physics 2025-10-21 Peter W. Evans

The resource theories of quantum coherence attract a lot of attention in recent years. Especially, the monotonicity property plays a crucial role here. In this paper we investigate the monotonicity property for the coherence measures…

Quantum Physics · Physics 2017-08-02 Lian-He Shao , Yongming Li , Yu Luo , Zhengjun Xi

T. Riviere proved an energy quantization for Yang-Mills fields defined on n-dimensional Riemannian manifolds, when $n$ is larger than the critical dimension 4. More precisely, he proved that the defect measure of a weakly converging…

Analysis of PDEs · Mathematics 2007-05-23 Fethi Mahmoudi

We study successive measurements of two observables using von Neumann's measurement model. The two-pointer correlation for arbitrary coupling strength allows retrieving the initial system state. We recover Luders rule, the Wigner formula…

Quantum Physics · Physics 2009-01-22 Lars M. Johansen , Pier A. Mello

Measurements take a singular role in quantum theory. While they are often idealized as an instantaneous process, this is in conflict with all other physical processes in nature. In this Letter, we adopt a standpoint where the interaction…

Quantum Physics · Physics 2023-11-15 Nathan Shettell , Federico Centrone , Luis Pedro García-Pintos

Three recent arguments seek to show that the universal applicability of unitary quantum theory is inconsistent with the assumption that a well-conducted measurement always has a definite physical outcome. In this paper I restate and analyze…

Quantum Physics · Physics 2018-10-17 Richard A. Healey

Quantum mechanics sets severe limits on the sensitivity and required circulating energy in traditional free-mass gravitational-wave antennas. One possible way to avoid these restrictions is the use of intracavity QND measurements. We…

Quantum Physics · Physics 2009-10-31 Vladimir B. Braginsky , Michael L. Gorodetsky , Farid Ya. Khalili

Quantum theory in its conventional formulation is notoriously subject to various measurement-related paradoxes, as exemplified by the "Schrodinger's Cat" and "Wigner's Friend" thought experiments. It has been shown, for example by…

Quantum Physics · Physics 2024-10-04 R. E. Kastner

Quantum measurement is a physical process. What physical resources and constraints does quantum mechanics require for measurement to produce the classical world we observe? Treating measurement as a fully unitary quantum process, our goal…

Quantum Physics · Physics 2025-12-09 Vishal Johnson , Ashmeet Singh , Reimar Leike , Philipp Frank , Torsten Enßlin

The notion of state reduction employed by the standard quantum theory of measurement is difficult to accept for two reasons: It leaves open where and when the reduction takes place and it does not give any objective conditions under which…

Quantum Physics · Physics 2013-08-28 Petr Hajicek

In this essay, we argue that certain aspects of the measurement require revision in Quantum Gravity. Using entropic arguments, we propose that the number of measurement outcomes and the accuracy (or the range) of the measurement are limited…

High Energy Physics - Theory · Physics 2024-08-28 Juanca Carrasco-Martinez

According to quantum theory, the outcomes of future measurements cannot (in general) be predicted with certainty. In some cases, even with a complete physical description of the system to be measured and the measurement apparatus, the…

Quantum Physics · Physics 2012-07-16 Terence E. Stuart , Joshua A. Slater , Roger Colbeck , Renato Renner , Wolfgang Tittel

Analysing Quantum Measurement requires analysing the physics of amplification since amplification of phenomena from one scale to another scale is essential to measurement. There still remains the task of working this into an axiomatic…

Quantum Physics · Physics 2007-05-23 Joseph F. Johnson