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Related papers: Path summation and quantum measurements

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We derive stochastic master equation for a quantum system interacting with an environment prepared in a continuous-mode $N$-photon state. To determine the conditional evolution of the quantum system depending on continuous in time…

Quantum Physics · Physics 2020-02-11 Anita Dąbrowska , Gniewomir Sarbicki , Dariusz Chruściński

This paper aims to provide a consistent, finite-valued, and mathematically well-defined reformulation of the Feynman path-integral measure for quantum fields obtained by studying the Wiener stochastic process in the infinite-dimensional…

High Energy Physics - Theory · Physics 2024-06-18 A. A. Varshovi

We show that QM can be represented as a natural projection of a classical statistical model on the phase space $\Omega= H\times H,$ where $H$ is the real Hilbert space. Statistical states are given by Gaussian measures on $\Omega$ having…

Quantum Physics · Physics 2007-05-23 Andrei Khrennikov

We propose in this paper an alternative method for the quantisation of systems with first-class constraints. This method is a combination of the coherent-state-path-integral quantisation developed by Klauder, with the ideas of reduced state…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Charis Anastopoulos

We consider three types of entities for quantum measurements. In order of generality, these types are: observables, instruments and measurement models. If $\alpha$ and $\beta$ are entities, we define what it means for $\alpha$ to be a part…

Quantum Physics · Physics 2022-09-01 Stan Gudder

We present a new model for the continuous measurement of a coupled quantum dot charge qubit. We model the effects of a realistic measurement, namely adding noise to, and filtering, the current through the detector. This is achieved by…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 Neil P. Oxtoby , P. Warszawski , H. M. Wiseman , He-Bi Sun , R. E. S. Polkinghorne

Non-relativistic quantum mechanics is reformulated here based on the idea that relational properties among quantum systems, instead of the independent properties of a quantum system, are the most fundamental elements to construct quantum…

Quantum Physics · Physics 2021-04-20 Jianhao M. Yang

We develop a general framework to study quantum trajectories resulting from repeated random measurements subject to stationary noise, and generalize results of K\"ummerer and Maassen to this setting. The resulting trajectory of quantum…

Quantum Physics · Physics 2025-11-13 Owen Ekblad , Eloy Moreno-Nadales , Lubashan Pathirana , Jeffrey Schenker

Quantum trajectories are Markov processes describing the evolution of a quantum system subject to indirect measurements. They can be viewed as place dependent iterated function systems or the result of products of dependent and non…

Probability · Mathematics 2024-09-30 Tristan Benoist , Clément Pellegrini , Anna Szczepanek

Decoherence of a quantum system induced by the interaction with its environment (measuring medium) may be presented phenomenologically as a continuous (or repeated) fuzzy quantum measurement. The dynamics of the system subject to continuous…

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

Biconformal spaces contain the essential elements of quantum mechanics, making the independent imposition of quantization unnecessary. Based on three postulates characterizing motion and measurement in biconformal geometry, we derive…

High Energy Physics - Theory · Physics 2010-11-11 Lara B. Anderson , James T. Wheeler

Counting statistics of charge transfers in a point contact interacting with an arbitrary quantum system is studied. The theory for the charge specific density matrix is developed, allowing the evaluation of the probability of the outcome of…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 J. Rammer , A. L. Shelankov , J. Wabnig

A quantum mechanical theory is proposed which abandons an external parameter ``time'' in favor of a self-adjoint operator on a Hilbert space whose elements represent measurement events rather than system states. The standard quantum…

Quantum Physics · Physics 2009-09-29 Kim Bostroem

We introduce a measure of average dimensionality (or coherence) for high-dimensional quantum devices. This includes sets of quantum measurements, steering assemblages, and quantum channels. For measurements and channels, our measure…

Quantum Physics · Physics 2023-06-22 Thomas Cope , Roope Uola

One of the main postulates of quantum mechanics is that measurements destroy quantum coherence (wave function collapse). Recently it was discovered that in a many-body system dilute local measurements still preserve some coherence across…

Quantum Physics · Physics 2025-05-13 Aleksei Khindanov , Igor L. Aleiner , Lara Faoro , Lev B. Ioffe

Quantum state tomography is a technique in quantum information science used to reconstruct the density matrix of an unknown quantum state, providing complete information about the quantum state. It is of significant importance in fields…

Quantum Physics · Physics 2025-07-23 Wenlong Zhao , Da Zhang , Huili Zhang , Haifeng Yu , Zhang-qi Yin

Measurement is a fundamental notion in the usual approximate quantum mechanics of measured subsystems. Probabilities are predicted for the outcomes of measurements. State vectors evolve unitarily in between measurements and by reduction of…

General Relativity and Quantum Cosmology · Physics 2014-01-14 James B. Hartle

Information-theoretical restrictions on the information transfer in quantum measurements are studied. They are derived for the measurement of system S by detector D, registrated and processed by information system O. The formalism of…

Quantum Physics · Physics 2007-06-28 S. Mayburov

In measurement-based quantum computation, quantum algorithms are implemented via sequences of measurements. We describe a translationally invariant finite-range interaction on a one-dimensional qudit chain and prove that a single-shot…

Quantum Physics · Physics 2009-11-13 Dominik Janzing , Pawel Wocjan , Shengyu Zhang

It is proposed a possible new approach of quantum measurements (QMS), disconnected of the traditional interpretation of uncertainty relations and independent of any appeal to the strange idea of collapse (reduction) of wave functions. The…

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