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Related papers: Improved unitary uncertainty relations

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In this paper, we use certain norm inequalities to obtain new uncertain relations based on the Wigner-Yanase skew information. First for an arbitrary finite number of observables we derive an uncertainty relation outperforming previous…

Quantum Physics · Physics 2020-08-26 Xiaofen Huang , Tinggui Zhang , Naihuan Jing

Uncertainty relation is one of the fundamental building blocks of quantum theory. Nevertheless, the traditional uncertainty relations do not fully capture the concept of incompatible observables. Here we present a stronger…

Quantum Physics · Physics 2017-01-05 Qiu-Cheng Song , Cong-Feng Qiao

The uncertainty relation is a distinguishing feature of quantum theory, characterizing the incompatibility of noncommuting observables in the preparation of quantum states. Recently, many uncertainty relations were proposed with improved…

Quantum Physics · Physics 2017-12-25 Zhi-Xin Chen , Jun-Li Li , Qiu-Cheng Song , Hui Wang , S. M. Zangi , Cong-Feng Qiao

We utilize quantum superposition principle to establish the improvable upper and lower bounds on the stronger uncertainty relation, i.e., the "weighted-like" sum of the variances of observables. Our bounds include some free parameters which…

Quantum Physics · Physics 2017-04-17 Jun Zhang , Yang Zhang , Chang-shui Yu

Uncertainty relations are old, yet potentially rewarding to explore. By introducing a quantity called the uncertainty matrix, we provide a link between purity and observable incompatibility, and derive several stronger uncertainty relations…

Quantum Physics · Physics 2018-07-02 Chiranjib Mukhopadhyay , Arun Kumar Pati

We derive several uncertainty relations for two arbitrary unitary operators acting on physical states of a Hilbert space. We show that our bounds are tighter in various cases than the ones existing in the current literature. Using the…

Quantum Physics · Physics 2016-10-12 Shrobona Bagchi , Arun Kumar Pati

We derive two quantum uncertainty relations for position and momentum coarse-grained measurements. Building on previous results, we first improve the lower bound for uncertainty relations using the Renyi entropy, particularly in the case of…

Quantum Physics · Physics 2012-11-06 Łukasz Rudnicki , Stephen P. Walborn , Fabricio Toscano

We construct a multi-observable uncertainty equality as well as an inequality based on the sum of standard deviations in the qubit system. The obtained equality indicates that the uncertainty relation can be expressed more accurately, and…

Quantum Physics · Physics 2020-06-08 Xiao Zheng , Shaoqiang Ma , Guofeng Zhang

Uncertainty relations are pivotal in delineating the limits of simultaneous measurements for observables. In this paper, we derive four novel uncertainty and reverse uncertainty relations for the sum of variances of two incompatible…

Quantum Physics · Physics 2025-08-05 M. Y. Abd-Rabbou , Cong-Feng Qiao

A smooth function of the second moments of $N$ continuous variables gives rise to an uncertainty relation if it is bounded from below. We present a method to systematically derive such bounds by generalizing an approach applied previously…

Quantum Physics · Physics 2016-10-18 Spiros Kechrimparis , Stefan Weigert

Uncertainty relations provide constraints on how well the outcomes of incompatible measurements can be predicted, and, as well as being fundamental to our understanding of quantum theory, they have practical applications such as for…

Quantum Physics · Physics 2013-05-30 Patrick J. Coles , Roger Colbeck , Li Yu , Michael Zwolak

Heisenberg-Robertson's uncertainty relation expresses a limitation in the possible preparations of the system by giving a lower bound to the product of the variances of two observables in terms of their commutator. Notably, it does not…

Quantum Physics · Physics 2015-01-07 Lorenzo Maccone , Arun K. Pati

We present a versatile inequality of uncertainty relations which are useful when one approximates an observable and/or estimates a physical parameter based on the measurement of another observable. It is shown that the optimal choice for…

Quantum Physics · Physics 2016-07-22 Jaeha Lee , Izumi Tsutsui

Recently, Maccone and Pati have given two stronger uncertainty relations based on the sum of variances and one of them is nontrivial when the quantum state is not an eigenstate of the sum of the observables. We derive a family of weighted…

Quantum Physics · Physics 2016-03-29 Yunlong Xiao , Naihuan Jing , Xianqing Li-Jost , Shao-Ming Fei

Uncertainty relations are a distinctive characteristic of quantum theory that impose intrinsic limitations on the precision with which physical properties can be simultaneously determined. The modern work on uncertainty relations employs…

Quantum Physics · Physics 2013-12-16 Shmuel Friedland , Vlad Gheorghiu , Gilad Gour

Uncertainty principle is one of the most essential features in quantum mechanics and plays profound roles in quantum information processing. We establish tighter summation form uncertainty relations based on metric-adjusted skew information…

Quantum Physics · Physics 2024-06-26 Cong Xu , Qing-Hua Zhang , Shao-Ming Fei

The entropic uncertainty relation proven by Maassen and Uffink for arbitrary pairs of two observables is known to be non-optimal. Here, we call an uncertainty relation optimal, if the lower bound can be attained for any value of either of…

We introduce two uncertainty relations based on the state-dependent norm of commutators, utilizing generalizations of the B\"ottcher-Wenzel inequality. The first relation is mathematically proven, while the second, tighter relation is…

Quantum Physics · Physics 2024-12-30 Aina Mayumi , Gen Kimura , Hiromichi Ohno , Dariusz Chruściński

We derive and experimentally investigate a strong uncertainty relation valid for any $n$ unitary operators, which implies the standard uncertainty relation as a special case, and which can be written in terms of geometric phases. It is…

We study uncertainty relations for pairs of conjugate variables like number and angle, of which one takes integer values and the other takes values on the unit circle. The translation symmetry of the problem in either variable implies that…

Quantum Physics · Physics 2018-04-03 Paul Busch , Jukka Kiukas , Reinhard F. Werner