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Related papers: Real-Valued Observables and Quantum Uncertainty

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Minimum-uncertainty squeezed states, related to a broad class of observables, are analyzed. Methods for characterizing such states are developed, which are based on numerical solutions of ordinary differential equations. As typical examples…

Quantum Physics · Physics 2007-12-24 E. Shchukin , W. Vogel , Th. Kiesel

We investigate the product form uncertainty relations of variances for $n\,(n\geq 3)$ quantum observables. In particular, tight uncertainty relations satisfied by three observables has been derived, which is shown to be better than the ones…

Quantum Physics · Physics 2016-08-12 Hui-Hui Qin , Shao-Ming Fei , Xianqing Li-Jost

We describe a scheme for the exploration of quantum gravity phenomenology focussing on effects that could be thought as arising from a fundamental granularity of space-time. In contrast with the simplest assumptions, such granularity is…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Yuri Bonder , Daniel Sudarsky

Constructive techniques to establish state-independent uncertainty relations for the sum of variances of arbitrary two observables are presented. We investigate the range of simultaneously attainable pairs of variances, which can be applied…

Quantum Physics · Physics 2019-04-26 Konrad Szymański , Karol Życzkowski

The uncertainty principle is often interpreted by the tradeoff between the error of a measurement and the consequential disturbance to the followed ones, which originated long ago from Heisenberg himself but now falls into reexamination and…

Quantum Physics · Physics 2018-03-29 Yu-Xiang Zhang , Shengjun Wu , Zeng-Bing Chen

Unsolved controversies about uncertainty relations and quantum measurements still persists nowadays. They originate around the shortcomings regarding the conventional interpretation of uncertainty relations. Here we show that the respective…

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

For sharp quantum observables the following facts hold: (i) if we have a collection of sharp observables and each pair of them is jointly measurable, then they are jointly measurable all together; (ii) if two sharp observables are jointly…

Quantum Physics · Physics 2008-12-08 Teiko Heinosaari , Daniel Reitzner , Peter Stano

In standard formulations of the uncertainty principle, two fundamental features are typically cast as impossibility statements: two noncommuting observables cannot in general both be sharply defined (for the same state), nor can they be…

Quantum Physics · Physics 2018-06-08 Tom Bullock , Paul Busch

From the premise that an observable is real after it is measured, we envisage a tomography-based protocol that allows us to propose a quantifier for the degree of indefiniteness of an observable given a quantum state. Then, we find that the…

Quantum Physics · Physics 2015-12-08 A. L. O. Bilobran , R. M. Angelo

Here the probability density of relativistic particles coordinates, satisfying the formal conditions of the quantum mechanics and the special relativity, is determined (under textbooks view, such density does not exist). It is specified for…

Quantum Physics · Physics 2009-03-17 V. F. Krotov

We demonstrate that quantum instruments can provide a unified operational foundation for quantum theory. Since these instruments directly correspond to laboratory devices, this foundation provides an alternate, more experimentally grounded,…

Quantum Physics · Physics 2013-08-13 Justin Dressel , Andrew N. Jordan

We formulate uncertainty relations for arbitrary $N$ observables. Two uncertainty inequalities are presented in terms of the sum of variances and standard deviations, respectively. The lower bounds of the corresponding sum uncertainty…

Quantum Physics · Physics 2015-09-24 Bin Chen , Shao-Ming Fei

The fundamental physical description of the Universe is based on two theories: Quantum Mechanics and General Relativity. Unified theory of Quantum Gravity (QG) is an open problem. Quantum Gravity Phenomenology (QGP) studies QG effects in…

General Relativity and Quantum Cosmology · Physics 2021-08-11 Vasil Todorinov

We discuss some applications of various versions of uncertainty relations for both discrete and continuous variables in the context of quantum information theory. The Heisenberg uncertainty relation enables demonstration of the EPR paradox.…

Quantum Physics · Physics 2014-10-23 Archan S. Majumdar , Tanumoy Pramanik

The formalism of covariant quantum theory, introduced by Reisenberger and Rovelli, casts the description of quantum states and evolution into a framework compatable with the principles of general relativity. The leap to this covariant…

Quantum Physics · Physics 2008-02-13 S. Jay Olson , Jonathan P. Dowling

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

We propose a unifying approach to the separability problem using covariance matrices of locally measurable observables. From a practical point of view, our approach leads to strong entanglement criteria that allow to detect the entanglement…

Quantum Physics · Physics 2007-10-04 O. Gühne , P. Hyllus , O. Gittsovich , J. Eisert

Recently,D.Mondal et.al[Phys. Rev. A. 95, 052117(2017)]creatively introduce a new interesting concept of reverse uncertainty relation which indicates that one cannot only prepare quantum states with joint small uncertainty, but also with…

Quantum Physics · Physics 2023-08-28 Xiao Zheng , Ai-Ling Ji , Guo-Feng Zhang

We present a new scheme of defining invariant observables for general relativistic systems. The scheme is based on the introduction of an observer which endowes the construction with a straightforward physical interpretation. The…

General Relativity and Quantum Cosmology · Physics 2014-05-23 Paweł Duch , Wojciech Kamiński , Jerzy Lewandowski , Jedrzej Świeżewski

In quantum mechanics, the Heisenberg uncertainty relation presents an ultimate limit to the precision by which one can predict the outcome of position and momentum measurements on a particle. Heisenberg explicitly stated this relation for…

Quantum Physics · Physics 2020-11-16 Han Bao , Shenchao Jin , Junlei Duan , Suotang Jia , Klaus Mølmer , Heng Shen , Yanhong Xiao