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Related papers: Higher-order uncertainty bounds for mixed states

200 papers

The uncertainty relation is one of the key ingredients of quantum theory. Despite the great efforts devoted to this subject, most of the variance-based uncertainty relations are state-dependent and suffering from the triviality problem of…

Quantum Physics · Physics 2018-03-08 Chen Qian , Jun-Li Li , Cong-Feng Qiao

The laws of quantum mechanics place fundamental limits on the accuracy of measurements and therefore on the estimation of unknown parameters of a quantum system. In this work, we prove lower bounds on the size of confidence regions reported…

Quantum Physics · Physics 2014-12-23 Michael Walter , Joseph M. Renes

Measurement uncertainty relations are quantitative bounds on the errors in an approximate joint measurement of two observables. They can be seen as a generalization of the error/disturbance tradeoff first discussed heuristically by…

Quantum Physics · Physics 2014-05-01 Paul Busch , Pekka Lahti , Reinhard F Werner

Heisenberg's uncertainty principle is formulated for a set of generalized measurements within the framework of majorization theory, resulting in a partial uncertainty order on probability vectors that is stronger than those based on…

Quantum Physics · Physics 2012-10-26 M. Hossein Partovi

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

Uncertainty relations (URs) like the Heisenberg-Robertson or the time-energy UR are often considered to be hallmarks of quantum theory. Here, a simple derivation of these URs is presented based on a single classical inequality from…

Quantum Physics · Physics 2015-09-14 Florian Fröwis , Roman Schmied , Nicolas Gisin

Heisenberg's uncertainty principle states that the position and momentum of a particle cannot be sharply determined simultaneously. Standard-deviation and entropic formulations capture the spread of the probability distribution but say…

Quantum Physics · Physics 2026-05-07 Jia-Yi Lin , Xin-Yu Li , Wei Wang , Shengjun Wu

We present observable upper bounds of squared concurrence, which are the dual inequalities of the observable lower bounds introduced in [F. Mintert and A. Buchleitner, Phys. Rev. Lett. 98, 140505 (2007)] and [L. Aolita, A. Buchleitner and…

Quantum Physics · Physics 2009-11-13 Cheng-Jie Zhang , Yan-Xiao Gong , Yong-Sheng Zhang , Guang-Can Guo

The optimal state-independent lower bounds for the sum of variances or deviations of observables are of significance for the growing number of experiments that reach the uncertainty limited regime. We present a framework for computing the…

Quantum Physics · Physics 2021-11-02 Lin Zhang , Shunlong Luo , Shao-Ming Fei , Junde Wu

We consider the Unambiguous State Discrimination (USD) of two mixed quantum states. We study the rank and the spectrum of the elements of an optimal USD measurement. This naturally leads to a partial fourth reduction theorem. This theorem…

Quantum Physics · Physics 2007-12-11 Philippe Raynal , Norbert Lütkenhaus

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 study the sum uncertainty relations based on variance and skew information for arbitrary finite N quantum mechanical observables. We derive new uncertainty inequalities which improve the exiting results about the related uncertainty…

Quantum Physics · Physics 2021-11-18 Qing-Hua Zhang , Shao-Ming Fei

We derive universal upper estimates for model-prediction error under moderate but otherwise unknown model uncertainty. Our estimates give upper bounds on the leading order trajectory-uncertainty arising along model trajectories, solely as…

Chaotic Dynamics · Physics 2021-02-03 Bálint Kaszás , George Haller

We show that the uncertainty relation as expressed in the Robertson-Schrodinger generalized form can be used to detect the mixedness of three-level quantum systems in terms of measureable expectation values of suitably chosen observables…

Quantum Physics · Physics 2013-03-14 S. Mal , T. Pramanik , A. S. Majumdar

This paper proposes hybrid high-order eigensolvers for the computation of guaranteed lower eigenvalue bounds. These bounds display higher order convergence rates and are accessible to adaptive mesh-refining algorithms. The involved…

Numerical Analysis · Mathematics 2026-04-23 Ngoc Tien Tran

We study entropic uncertainty relations by using stepwise linear functions and quadratic functions. Two kinds of improved uncertainty lower bounds are constructed: the state-independent one based on the lower bound of Shannon entropy and…

Quantum Physics · Physics 2018-11-14 Zhihua Chen , Zhihao Ma , Yunlong Xiao , Shao-Ming Fei

In this thesis we study the problem of unambiguously discriminating two mixed quantum states. We first present reduction theorems for optimal unambiguous discrimination of two generic density matrices. We show that this problem can be…

Quantum Physics · Physics 2007-05-23 Philippe Raynal

In this paper, we consider Wigner-Yanase-Dyson information as a measure of quantum uncertainty of a mixed state. We study some of the interesting properties of this generalized measure. The construction is reminiscent of the generalized…

Quantum Physics · Physics 2009-04-03 D. Li , X. Li , H. Huang , X. Li , L. C. Kwek

Quantification of coherence lies at the heart of quantum information processing and fundamental physics. Exact evaluation of coherence measures generally needs a full reconstruction of the density matrix, which becomes intractable for…

Quantum Physics · Physics 2021-06-28 Qi-Ming Ding , Xiao-Xu Fang , Xiao Yuan , Ting Zhang , He Lu

Measurement uncertainty relations are lower bounds on the errors of any approximate joint measurement of two or more quantum observables. The aim of this paper is to provide methods to compute optimal bounds of this type. The basic method…

Quantum Physics · Physics 2016-06-08 René Schwonnek , David Reeb , Reinhard F. Werner