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Related papers: Quantum non-demolition measurements: Concepts, the…

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Quantum mechanics predicts the joint probability distribution of the outcomes of simultaneous measurements of commuting observables, but, in the state of the art, has lacked the operational definition of simultaneous measurements. The…

Quantum Physics · Physics 2009-10-31 Masanao Ozawa

The geometrical description of Quantum Mechanics is reviewed and proposed as an alternative picture to the standard ones. The basic notions of observables, states, evolution and composition of systems are analised from this perspective, the…

Mathematical Physics · Physics 2019-03-26 Florio M. Ciaglia , Alberto Ibort , Giuseppe Marmo

When quantum states are used to send classical information, the receiver performs a measurement on the signal states. The amount of information extracted is often not optimal due to the receiver's measurement scheme and experimental…

Quantum Physics · Physics 2018-04-25 Rui Han , Gerd Leuchs , Markus Grassl

Both classical and respectively quantum observables can be modeled as somewhat similar examples of random variables. In such a model the associated measurements preserve the values spectrum of an observable but change the corresponding…

Statistical Mechanics · Physics 2008-03-20 S. Dumitru , A. Boer

Although nondemolition, reliable, and instantaneous quantum measurements of some nonlocal variables are impossible, demolition reliable instantaneous measurements are possible for all variables. It is shown that this is correct also in the…

Quantum Physics · Physics 2009-11-11 Lev Vaidman , Izhar Nevo

Considering ultracold atoms traversing a high-Q Fabry-Perot cavity, we theoretically demonstrate a quantum nondemolition measurement of the photon number. This fully quantum mechanical approach may be understood utilizing concepts as…

Quantum Physics · Physics 2009-11-13 Jonas Larson , Mahmoud Abdel-Aty

The paper gives a systematic review of the basic ideas of (non-relativistic) quantum mechanics including all changes that result from previous work of the authors. This shows that the new theory is self-consistent and (in certain sense)…

Quantum Physics · Physics 2011-02-24 Petr Hajicek , Jiri Tolar

These are expanded lecture notes of a mini-course whose objectives were to introduce the basic concepts, constructions and techniques of noncommutative geometry, as well as their uses as a framework for modelling quantum spacetime. Key…

High Energy Physics - Theory · Physics 2025-12-08 Richard J. Szabo

Quantum mechanics predicts that measurements of incompatible observables carry a minimum uncertainty which is independent of technical deficiencies of the measurement apparatus or incomplete knowledge of the state of the system. Nothing yet…

Quantum Physics · Physics 2013-06-14 Davide Girolami , Tommaso Tufarelli , Gerardo Adesso

Every measurement on a quantum system causes a state change from the system state just before the measurement to the system state just after the measurement conditional upon the outcome of measurement. This paper determines all the possible…

Quantum Physics · Physics 2009-11-06 Masanao Ozawa

Quantum metrology holds the promise of an early practical application of quantum technologies, in which measurements of physical quantities can be made with much greater precision than what is achievable with classical technologies. In this…

Quantum Physics · Physics 2021-01-27 Jasminder S. Sidhu , Pieter Kok

Measurements destroy entanglement. Building on ideas used to study `quantum disentangled liquids', we explore the use of this effect to characterize states of matter. We focus on systems with multiple components, such as charge and spin in…

Strongly Correlated Electrons · Physics 2020-03-25 Daniel Ben-Zion , John McGreevy , Tarun Grover

We propose a scheme to realize a quantum non-demolition (QND) measurement of a superconducting flux qubit by a Josephson bifurcation amplifier. Our scheme can implement a perfect QND measurement for a qubit subject to a variable magnetic…

Mesoscale and Nanoscale Physics · Physics 2013-05-29 Ying-Dan Wang , Xiaobo Zhu , Christoph Bruder

The quantum mechanical measurement problem is the difficulty of dealing with the indefiniteness of the pointer observable at the conclusion of a measurement process governed by unitary quantum dynamics. There has been hope to solve this…

Quantum Physics · Physics 2007-05-23 P. Busch , A. Shimony

The concept of intrinsic and operational observables in quantum mechanics is introduced. In any realistic description of a quantum measurement that includes a macroscopic detecting device, it is possible to construct from the statistics of…

Quantum Physics · Physics 2016-09-08 B. G. Englert , K. Wodkiewicz

Through a new interpretation of Special Theory of Relativity and with a model given for physical space, we can find a way to understand the basic principles of Quantum Mechanics consistently from Classical Theory. It is supposed that…

Quantum Physics · Physics 2009-09-25 Kiyoung Kim

Quantum measurement is a fundamental cornerstone of experimental quantum computations. The main issues in current quantum measurement strategies are the high number of measurement rounds to determine a global optimal measurement output and…

Quantum Physics · Physics 2019-05-02 Laszlo Gyongyosi , Sandor Imre

In the measurement of a continuous observable Q, the pure components of the reduced state do, in general, depend on the initial state. For measurements which attempt to localize the measured system in a certain region R, the localized wave…

High Energy Physics - Phenomenology · Physics 2007-05-23 Kai J. Druhl

The standard presentation of the principles of quantum mechanics is critically reviewed both from the experimental/operational point and with respect to the request of mathematical consistency and logical economy. A simpler and more…

Quantum Physics · Physics 2012-02-02 F. Strocchi

Precision physics aims to use atoms and molecules to test and develop the fundamental theory of matter, possibly beyond the Standard Model. Most of the atomic and molecular phenomena are described by the QED (quantum electrodynamics) sector…

Chemical Physics · Physics 2024-06-11 Ádám Nonn , Ádám Margócsy , Edit Mátyus