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Related papers: An entropic uncertainty principle for mixed states

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An essential quantity in quantum information theory is the von Neumann entropy which depends entirely on the quantum density operator. Once known, the density operator reveals the statistics of observables in a quantum process, and the…

Systems and Control · Electrical Eng. & Systems 2023-09-08 Mark Balas , Vinod P. Gehlot , Tristan D. Griffith

One of the defining traits of quantum mechanics is the uncertainty principle which was originally expressed in terms of the standard deviation of two observables. Alternatively, it can be formulated using entropic measures, and can also be…

Quantum Physics · Physics 2015-09-30 Göktuğ Karpat , Jyrki Piilo , Sabrina Maniscalco

By carrying out appropriate continuous quantum measurements with a family of projection operators, a unitary channel can be approximated in an arbitrary precision in the trace norm sense. In particular, the quantum Zeno effect is described…

Mathematical Physics · Physics 2013-12-10 Toru Fuda

For a system randomly prepared in a number of quantum states, we present a lower bound for the distinguishability of the quantum states, that is, the success probability of determining the states in the form of entropy. When the states are…

Quantum Physics · Physics 2015-11-11 Seungho Yang , Jinhyoung Lee , Hyunseok Jeong

Coherence of a quantum state intrinsically depends on the choice of the reference basis. A natural question to ask is the following: if we use two or more incompatible reference bases, can~there be some trade-off relation between the…

Quantum Physics · Physics 2016-07-20 Uttam Singh , Arun Kumar Pati , Manabendra Nath Bera

We prove an entropic uncertainty relation for two quantum channels, extending the work of Frank and Lieb for quantum measurements. This is obtained via a generalized strong super-additivity (SSA) of quantum entropy. Motivated by Petz's…

Quantum Physics · Physics 2023-01-23 Li Gao , Marius Junge , Nicholas LaRacuente

Uncertainty principle is an inherent nature of quantum system that undermines the precise measurement of incompatible observables and hence the applications of quantum theory. Entanglement, another unique feature of quantum physics, was…

Quantum Physics · Physics 2020-09-30 Jun-Li Li , Cong-Feng Qiao

Heisenberg's uncertainty principle implies fundamental constraints on what properties of a quantum system can we simultaneously learn. However, it typically assumes that we probe these properties via measurements at a single point in time.…

Quantum Physics · Physics 2023-06-21 Yunlong Xiao , Yuxiang Yang , Ximing Wang , Qing Liu , Mile Gu

Quantum coherence characterizes the non-classical feature of a single party system with respect to a local basis. Based on a recently introduced resource framework, coherence can be regarded as a resource and be systematically manipulated…

Quantum Physics · Physics 2018-09-26 Yunchao Liu , Qi Zhao , Xiao Yuan

The uncertainty principle is one of the key concepts in quantum theory. This principle states that it is not possible to measure two incompatible observables simultaneously and accurately. In quantum information theory, the uncertainty…

Quantum Physics · Physics 2020-06-25 Soroush Haseli , Saeed Haddadi , Mohammad Reza Pourkarimi

In quantum information theory, von Neumann entropy plays an important role. The entropies can be obtained analytically only for a few states. In continuous variable system, even evaluating entropy numerically is not an easy task since the…

Quantum Physics · Physics 2015-05-13 Xiao-yu Chen

We show that a proper expression of the uncertainty relation for a pair of canonically-conjugate continuous variables relies on entropy power, a standard notion in Shannon information theory for real-valued signals. The resulting…

Quantum Physics · Physics 2018-01-16 Anaelle Hertz , Michael G. Jabbour , Nicolas J. Cerf

We analyze entropic uncertainty relations in a finite dimensional Hilbert space and derive several strong bounds for the sum of two entropies obtained in projective measurements with respect to any two orthogonal bases. We improve the…

Quantum Physics · Physics 2015-06-30 Łukasz Rudnicki , Zbigniew Puchała , Karol Życzkowski

The von Neumann entropy is a key quantity in quantum information theory and, roughly speaking, quantifies the amount of quantum information contained in a state when many identical and independent i.i.d. copies of the state are available,…

Quantum Physics · Physics 2019-06-05 P. Boes , J. Eisert , R. Gallego , M. P. Mueller , H. Wilming

The von Neumann entropy of an $n$-partite system $A_1^n$ given a system $B$ can be written as the sum of the von Neumann entropies of the individual subsystems $A_k$ given $A_1^{k-1}$ and $B$. While it is known that such a chain rule does…

Quantum Physics · Physics 2024-12-10 Ashutosh Marwah , Frédéric Dupuis

The uncertainty principle bounds the uncertainties about incompatible measurements, clearly setting quantum theory apart from the classical world. Its mathematical formulation via uncertainty relations, plays an irreplaceable role in…

Quantum Physics · Physics 2019-08-22 Yunlong Xiao , Kun Fang , Gilad Gour

We exhibit infinitely many new, constrained inequalities for the von Neumann entropy, and show that they are independent of each other and the known inequalities obeyed by the von Neumann entropy (basically strong subadditivity). The new…

Quantum Physics · Physics 2012-10-30 Josh Cadney , Noah Linden , Andreas Winter

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

We revisit generalized entropic formulations of the uncertainty principle for an arbitrary pair of quantum observables in two-dimensional Hilbert space. R\'enyi entropy is used as uncertainty measure associated with the distribution…

Quantum Physics · Physics 2014-06-23 Steeve Zozor , Gustavo Martín Bosyk , Mariela Portesi

We consider the problem of determining the mixed quantum state of a large but finite number of identically prepared quantum systems from data obtained in a sequence of ideal (von Neumann) measurements, each performed on an individual copy…

Quantum Physics · Physics 2009-11-10 Franz Embacher , Heide Narnhofer
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