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Related papers: Quantum Theory of Measurement

200 papers

In this paper, I attempt a personal account of my understanding of the measurement problem in quantum mechanics, which has been largely in the tradition of the Copenhagen interpretation. I assume that (i) the quantum state is a…

Quantum Physics · Physics 2015-07-21 Caslav Brukner

In this study, we present a modified quantum theory, denoted as $QT^\ast$, which introduces mass-dependent decoherence effects. These effects are derived by averaging the influence of a proposed global quantum fluctuation in position and…

Quantum Physics · Physics 2024-12-18 Heinz-Jürgen Schmidt

The quantum measurement problem, understanding why a unique outcome is obtained in each individual experiment, is tackled by solving models. After an introduction we review the many dynamical models proposed over the years. A flexible and…

Quantum Physics · Physics 2015-05-28 Armen E. Allahverdyan , Roger Balian , Theo M. Nieuwenhuizen

The paper discuss the structure of quantum mechanics and uniqueness of its postulates. The Born rule for quantum probabilities is fixed by requirement of nonexistence of quantum telepathy. Von Neumann projection postulate describes the…

Quantum Physics · Physics 2015-08-25 Mikhail G. Ivanov

Using the kinematic constraints of classical bodies we construct the allowable wavefunctions corresponding to classical solids. These are shown to be long lived metastable states that are qualitatively far from eigenstates of the true…

Quantum Physics · Physics 2013-09-05 Clifford E Chafin

This is an attempt to create a consistent and non-trivial extension of quantum theory, describing in detail the quantum measurement process. A tentative but concrete model is presented, based on the concept of multiple…

Quantum Physics · Physics 2007-05-23 Jose L Balduz

A reformulation of a physical theory in which measurements at the initial and final moments of time are treated independently is discussed, both on the classical and quantum levels. Methods of the standard quantum mechanics are used to…

Quantum Physics · Physics 2016-11-09 Pavel Krtous

The only evidence we have for a discrete reality comes from quantum measurements; without invoking these measurements, quantum theory describes continuous entities. This seeming contradiction can be resolved via analysis that treats…

Quantum Physics · Physics 2011-06-08 Ken Wharton

We investigate the extent to which ``interaction-free'' measurements perturb the state of quantum systems. We show that the absence of energy exchange during the measurement is not a sufficient criterion to preserve that state, as the…

Quantum Physics · Physics 2009-11-06 S. Potting , E. S. Lee , W. Schmitt , I. Rumyantsev , B. Mohring , P. Meystre

Quantum coherence is a key resource in quantum information processing scenarios, and quantifying coherence is an important task for both quantum foundation and quantum technology. However, until now, all most of coherence measures are…

Quantum Physics · Physics 2017-10-24 Wei-Chen Wang , Mao-Fa Fang , Min Yu

In quantum mechanics, randomness is postulated as a separate axiom. De Broglie's theory allows one to reproduce quantum phenomena from completely deterministic formalism. But the question of the quantum randomness emergency in the de…

Quantum Physics · Physics 2024-08-16 Aleksei M. Aleshin , Vladimir V. Nikitin , Petr I. Pronin

A natural formulation of the theory of quantum measurements in continuous time is based on quantum stochastic differential equations (Hudson-Parthasarathy equations). However, such a theory was developed only in the case of…

Probability · Mathematics 2011-11-30 Ricardo Castro Santis , Alberto Barchielli

Stochastic mechanics is regarded as a physical theory to explain quantum mechanics with classical terms such that some of the quantum mechanics paradoxes can be avoided. Here we propose a new variational principle to uncover more insights…

Quantum Physics · Physics 2025-12-02 Jianhao M. Yang

Measurements with randomly chosen settings determine many important properties of quantum states without the need for a shared reference frame or calibration. They naturally emerge in the context of quantum communication and quantum…

The restricted-path-integral (RPI) theory of continuous quantum measurements including the evolution of the measured systems and phenomenon of decoherence is reviewed. The measured system is considered as an open quantum system but without…

Quantum Physics · Physics 2007-05-23 Michael B. Mensky

It is shown that having degenerate ground states over the domain of the wavefunction of a system is a sufficient condition for a quantum system to act as a measuring apparatus for the system. Measurements are then instances of spontaneous…

Quantum Physics · Physics 2010-08-17 Partha Ghose

Nonlocality is a distinctive feature of quantum theory, which has been extensively studied for decades. It is found that the uncertainty principle determines the nonlocality of quantum mechanics. Here we show that various degrees of…

Quantum Physics · Physics 2023-06-14 Ma-Cheng Yang , Jun-Li Li , Cong-Feng Qiao

The existence of incompatible measurements, epitomized by Heisenberg's uncertainty principle, is one of the distinctive features of quantum theory. So far, quantum incompatibility has been studied for measurements that test the preparation…

Quantum Physics · Physics 2017-03-16 Michal Sedlak , Daniel Reitzner , Giulio Chiribella , Mario Ziman

A goal of most interpretations of quantum mechanics is to avoid the apparent intrusion of the observer into the measurement process. Such intrusion is usually seen to arise because observation somehow selects a single actuality from among…

Quantum Physics · Physics 2007-05-23 Bruce Rosenblum , Fred Kuttner

We formulate the error and disturbance in quantum measurement by invoking quantum estimation theory. The disturbance formulated here characterizes the non-unitary state change caused by the measurement. We prove that the product of the…

Quantum Physics · Physics 2011-06-14 Yu Watanabe , Masahito Ueda