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Related papers: What Quantum Measurements Measure

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The effects of any quantum measurement can be described by a collection of measurement operators {M_m} acting on the quantum state of the measured system. However, the Hilbert space formalism tends to obscure the relationship between the…

Quantum Physics · Physics 2009-11-07 Holger F. Hofmann

The superposition of quantum states lies at the heart of physics and has been recently found to serve as a versatile resource for quantum information protocols, defining the notion of quantum coherence. In this contribution, we report on…

Quantum Physics · Physics 2019-10-16 Valeria Cimini , Ilaria Gianani , Marco Sbroscia , Jan Sperling , Marco Barbieri

There has been a strong recent interest in applying quantum mechanics (QM) outside physics, including in cognitive science. We analyze the applicability of QM to two basic properties in opinion polling. The first property (response…

Neurons and Cognition · Quantitative Biology 2017-02-08 Andrei Khrennikov , Irina Basieva , Ehtibar N. Dzhafarov , Jerome R. Busemeyer

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

``Weak'', ``protective'', and ``delayed observation'' measurements are analyzed in the framework of the Bohm interpretation of quantum theory. It is argued that the above varieties of measurements manifest some difficulties of the Bohm…

Quantum Physics · Physics 2007-05-23 Yakir Aharonov , Lev Vaidman

Quantum measurement finds the observed system in a collapsed state, rather than in the state predicted by the Schr\"odinger equation. Yet there is a relatively spread opinion that the wavefunction collapse can be explained by unitary…

Quantum Physics · Physics 2016-02-08 Ovidiu Cristinel Stoica

If the block universe view is correct, the future and the past have similar status and one would expect physical theories to involve final as well as initial boundary conditions. A plausible consistency condition between the initial and…

Quantum Physics · Physics 2007-05-23 D. J. Miller

We develop the contextual measurement model (CMM) which is used for clarification of the quantum foundations. This model matches with Bohr's views on the role of experimental contexts. CMM is based on contextual probability theory which is…

Quantum Physics · Physics 2025-11-21 Andrei Khrennikov

Quantum mechanics is usually presented starting from a series of postulates about the mathematical framework. In this work we show that those same postulates can be derived by assuming that measurements are discrete interactions: that is,…

Quantum Physics · Physics 2008-01-08 Gabriele Carcassi

For theoretical approach of quantum measurements it is proposed a set of reconsidered conjectures. The proposed approach implies linear functional transformations for probability density and current but preserves the expressions for…

Quantum Physics · Physics 2007-05-23 S. Dumitru

In response to recent criticisms by Okon and Sudarsky, various aspects of the consistent histories (CH) resolution of the quantum measurement problem(s) are discussed using a simple Stern-Gerlach device, and compared with the alternative…

Quantum Physics · Physics 2015-07-29 Robert B. Griffiths

It is a crucial feature of quantum mechanics that not all measurements are compatible with each other. However, if measurements suffer from noise they may lose their incompatibility. Here, we consider the effect of white noise and determine…

Quantum Physics · Physics 2026-01-30 Martin J. Renner

Quantum sensing is commonly described as a constrained optimization problem: maximize the information gained about an unknown quantity using a limited number of particles. Important sensors including gravitational-wave interferometers and…

Quantum Physics · Physics 2020-08-05 Morgan W. Mitchell

We present the quantum measurement problem as a serious physics problem. Serious because without a resolution, quantum theory is not complete, as it does not tell how one should - in principle - perform measurements. It is physical in the…

Quantum Physics · Physics 2018-07-23 Nicolas Gisin

The more information a measurement provides about a quantum system's position statistics, the less information a subsequent measurement can provide about the system's momentum statistics. This information trade-off is embodied in the…

Quantum Physics · Physics 2016-05-16 Gregory A. Howland , James Schneeloch , Daniel J. Lum , John C. Howell

What is the observer's role in quantum measurement? Obviously, observers prepare the apparatus, observe and interpret the measured results. Although the observer will have a certain influence on the measurement results by setting up the…

Quantum Physics · Physics 2022-11-01 Lizhi Xin , Houwen Xin

Standard quantum measurements are projective. However, the full scope of quantum measurements is represented by positive operator-valued measures (POVMs) and many of these break the limitations of projective measurements as resources in…

A method is proposed that allows one to infer the sum of the values of an observable taken during contacts with a pointer state. Hereby the state of the pointer is updated while contacted with the system and remains unchanged between…

Statistical Mechanics · Physics 2020-11-06 Juzar Thingna , Peter Talkner

We establish connections between the requirement of measurability of a probability space and the principle of complimentarity in quantum mechanics. It is shown that measurability of a probability space implies the dependence of results of…

Quantum Physics · Physics 2007-05-23 D. A. Slavnov

Experimentally observed violations of Bell inequalities rule out local realistic theories. Consequently, the quantum state vector becomes a strong candidate for providing an objective picture of reality. However, such an ontological view of…

Quantum Physics · Physics 2007-05-23 Bernd A. Berg