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Related papers: Uncertainty from the Aharonov-Vaidman Identity

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We report a universal improvement to the standard Robertson--Schr\"odinger uncertainty relation. Our result shows that the Robertson--Schr\"odinger lower bound can be supplemented by a new noncommutativity-induced term. This term represents…

Quantum Physics · Physics 2026-05-19 Gen Kimura , Aina Mayumi , Hiromichi Ohno , Jaeha Lee , Dariusz Chruściński

We investigate a generic discrete quantum system prepared in state $|\psi_\text{in}\rangle$, under repeated detection attempts aimed to find the particle in state $|d\rangle$, for example a quantum walker on a finite graph searching for a…

Quantum Physics · Physics 2020-07-01 Felix Thiel , Itay Mualem , David A. Kessler , Eli Barkai

A universal formulation of uncertainty relations for quantum measurements is presented with additional focus on the representability of quantum observables by classical observables over a given state. Owing to the simplicity and operational…

Quantum Physics · Physics 2022-04-01 Jaeha Lee

We investigate the Peres-Horodecki positive partial transpose (PPT) criterion in the context of conserved quantities and derive a condition of in- separability for a composite bipartite system depending only on the dimen- sions of its…

Quantum Physics · Physics 2016-12-21 Ashutosh K. Goswami , Prasanta K. Panigrahi

We analyze the uncertainty relation for the sum of variances, which is called in some papers, the stronger uncertainty relation for all incompatible observables. We show that this uncertainty relation for the sum of variances of the…

Quantum Physics · Physics 2025-03-13 K. Urbanowski

We establish the tightest possible Robertson-type preparation uncertainty relation, which explicitly depends on the eigenvalues of the quantum state. The conventional constant $ \tfrac{1}{4} $ is replaced by a state-dependent coefficient…

Quantum Physics · Physics 2025-12-23 Gen Kimura , Aina Mayumi , Haruki Yamashita

In this Letter, we show that the fulfillment of uncertainty relations is a sufficient criterion for a quantum-mechanically permissible state. We specifically construct two pseudo-spin observables for an arbitrary non-positive Hermitian…

Quantum Physics · Physics 2009-11-13 Hyunchul Nha , M. Suhail Zubairy

Gaussian distribution of a quantum state with continuous spectrum is known to maximize the Shannon entropy at a fixed variance. Applying it to a pair of canonically conjugate quantum observables $\hat x$ and $\hat p$, quantum entropic…

Quantum Physics · Physics 2015-07-21 Wonmin Son

The Cramer-Rao bound, satisfied by classical Fisher information, a key quantity in information theory, has been shown in different contexts to give rise to the Heisenberg uncertainty principle of quantum mechanics. In this paper, we show…

Quantum Physics · Physics 2022-11-23 Yakov Bloch , Eliahu Cohen

We revisit the problem of the uncertainty relation for angle by using quantum hydrodynamics formulated in the stochastic variational method (SVM), where we need not define the angle operator. We derive both the Kennard and…

Quantum Physics · Physics 2020-04-09 J. -P. Gazeau , T. Koide

By invoking quantum estimation theory we formulate bounds of errors in quantum measurement for arbitrary quantum states and observables in a finite-dimensional Hilbert space. We prove that the measurement errors of two observables satisfy…

Quantum Physics · Physics 2013-05-29 Yu Watanabe , Takahiro Sagawa , Masahito Ueda

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

The uncertainty relation and the probability interpretation of quantum mechanics are intrinsically connected, as is evidenced by the evaluation of standard deviations. It is thus natural to ask if one can associate a very small uncertainty…

Quantum Physics · Physics 2015-03-17 Kazuo Fujikawa , Koichiro Umetsu

Calling the quantity; 2delta(A)delta(B)/|<[A, B]>|, with non-zero denominator, the uncertainty product ratio or UPR for the pair of observables, (A, B), it is shown that any non-zero correlation coefficient between two observables raises,…

Quantum Physics · Physics 2007-05-23 Gordon N. Fleming

The uncertainty principle is one of the fundamental features of quantum mechanics and plays a vital role in quantum information processing. We study uncertainty relations based on metric-adjusted skew information for finite quantum…

Quantum Physics · Physics 2023-02-21 Qing-Hua Zhang , Jing-Feng Wu , Xiaoyu Ma , Shao-Ming Fei

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

Uncertainty relations are fundamental in quantum mechanics. Here I propose state-independent variance-based uncertainty relations for two or more arbitrary observables in finite dimensional spaces. The uncertainty relations provide…

Quantum Physics · Physics 2021-07-28 Yichen Huang

The Heisenberg uncertainty relation, which links the uncertainties of the position and momentum of a particle, has an important footprint on the quantum behavior of a physical system. Analogous to this principle, we propose that…

Quantum Physics · Physics 2026-02-18 Pratik Sathe , Luis Pedro García-Pintos , Francesco Caravelli

Complementarity restricts the accuracy with which incompatible quantum observables can be jointly measured. Despite popular conception, the Heisenberg uncertainty relation does not quantify this principle. We report the experimental…

The well-known Robertson-Schroedinger uncertainty relations miss an irreducible lower bound. This is widely attributed to the lower bound's state-dependence. Therefore, Abbott \emph{et al.} introduced a general approach to derive tight…

Quantum Physics · Physics 2020-10-14 Stephan Sponar , Armin Danner , Kazuma Obigane , Simon Hack , Yuji Hasegawa