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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

Commutator-based entropic uncertainty relations in multidimensional position and momentum spaces are derived, twofold generalizing previous entropic uncertainty relations for one-mode states. They provide optimal lower bounds and imply the…

Quantum Physics · Physics 2021-08-02 Yichen Huang

Uncertainty relations describe the lower bound of product of standard deviations of observables. By revealing a connection between standard deviations of quantum observables and numerical radius of operators, we establish a universal…

Quantum Physics · Physics 2016-01-26 Jinchuan Hou , Kan He

We revisit entropic formulations of the uncertainty principle for an arbitrary pair of positive operator-valued measures (POVM) $A$ and $B$, acting on finite dimensional Hilbert space. Salicr\'u generalized $(h,\phi)$-entropies, including…

Quantum Physics · Physics 2015-06-18 S. Zozor , G. M. Bosyk , M. Portesi

Uncertainty relation lies at the heart of quantum mechanics, characterizing the incompatibility of non-commuting observables in the preparation of quantum states. An important question is how to improve the lower bound of uncertainty…

Quantum Physics · Physics 2017-05-25 Qiu-Cheng Song , Jun-Li Li , Guang-Xiong Peng , Cong-Feng Qiao

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

The uncertainty relation between angle and orbital angular momentum had not been formulated in a similar form as the uncertainty relation between position and linear momentum because the angle variable is not represented by a quantum…

Quantum Physics · Physics 2015-07-17 Shogo Tanimura

The information-theoretic formulation of quantum measurement uncertainty relations (MURs), based on the notion of relative entropy between measurement probabilities, is extended to the set of all the spin components for a generic spin s.…

Quantum Physics · Physics 2020-05-13 Alberto Barchielli , Matteo Gregoratti

The Heisenberg-Robertson uncertainty relation quantitatively expresses the impossibility of jointly sharp preparation of incompatible observables. However it does not capture the concept of incompatible observables because it can be trivial…

Quantum Physics · Physics 2016-05-25 Kunkun Wang , Xiang Zhan , Zhihao Bian , Jian Li , Yongsheng Zhang , Peng Xue

In this work we determine a lower bound to the mean value of the quantum potential for an arbitrary state. Furthermore, we derive a generalized uncertainty relation that is stronger than the Robertson-Schr\"odinger inequality and hence also…

Quantum Physics · Physics 2020-05-08 F. Nicacio , F. T. Falciano

Introductory courses on quantum mechanics usually include lectures on uncertainty relations, typically the inequality derived by Robertson and, perhaps, other statements. For the benefit of the lecturers, we present a unified approach --…

Quantum Physics · Physics 2023-12-18 Berthold-Georg Englert

Analyzing general uncertainty relations one can find that there can exist such pairs of non-commuting observables $A$ and $B$ and such vectors that the lower bound for the product of standard deviations $\Delta A$ and $\Delta B$ calculated…

Quantum Physics · Physics 2020-10-19 Krzysztof Urbanowski

A new lower boundary for the product of variances of two observables is obtained in the case, when these observables are entangled with the third one. This boundary can be higher than the Robertson--Schr\"odinger one. The special case of…

Quantum Physics · Physics 2017-11-13 V. V. Dodonov

We consider particles prepared by the von Neumann-L\"uders projection. For those particles the standard deviation of the momentum is discussed. We show that infinite standard deviations are not exceptions but rather typical. A necessary and…

Quantum Physics · Physics 2010-06-29 Thomas Schürmann , Ingo Hoffmann

A prominent formulation of the uncertainty principle identifies the fundamental quantum feature that no particle may be prepared with certain outcomes for both position and momentum measurements. Often the statistical uncertainties are…

Quantum Physics · Physics 2015-01-08 Fabian Furrer , Mario Berta , Marco Tomamichel , Volkher B. Scholz , Matthias Christandl

The well-known Robertson-Schr\"odinger uncertainty relations have state-dependent lower bounds which are trivial for certain states. We present a general approach to deriving tight state-independent uncertainty relations for qubit…

Quantum Physics · Physics 2016-02-26 Alastair A. Abbott , Pierre-Louis Alzieu , Michael J. W. Hall , Cyril Branciard

We analyze the weak and critical points of various uncertainty relations that follow from the inequalities for the norms of vectors in the Hilbert space of states of a quantum system. There are studied uncertainty relations for sums of…

Quantum Physics · Physics 2025-08-13 Krzysztof Urbanowski

Given two or more non-commuting observables, it is generally not possible to simultaneously assign precise values to each. This quantum mechanical uncertainty principle is widely understood to be encapsulated by some form of uncertainty…

Quantum Physics · Physics 2019-01-23 Paul Busch , Oliver Reardon-Smith

We consider the uncertainty between two pairs of local projective measurements performed on a multipartite system. We show that the optimal bound in any linear uncertainty relation, formulated in terms of the Shannon entropy, is additive.…

Quantum Physics · Physics 2018-03-28 Rene Schwonnek

For a pair of observables, they are called "incompatible", if and only if the commutator between them does not vanish, which represents one of the key features in quantum mechanics. The question is, how can we characterize the…

Quantum Physics · Physics 2019-10-02 Yunlong Xiao , Cheng Guo , Fei Meng , Naihuan Jing , Man-Hong Yung