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Related papers: Quantum measurements and entropic bounds on inform…

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We consider highly inaccurate measurements made on classical stochastic and quantum systems. In the quantum case such a \e{weak} measurement preserves coherence between the system's alternatives. We demonstrate that in both cases the…

Quantum Physics · Physics 2026-03-16 D. Sokolovski , D. Alonso , S. Brouard

Many important properties of quantum channels are quantified by means of entropic functionals. Characteristics of such a kind are closely related to different representations of a quantum channel. In the Jamio{\l}kowski-Choi representation,…

Quantum Physics · Physics 2013-07-23 Alexey E. Rastegin

The uncertainty principle brings out intrinsic quantum bounds on the precision of measuring non-commuting observables. Statistical outcomes in the measurement of incompatible observables reveal a trade-off on the sum of corresponding…

Quantum Physics · Physics 2013-11-11 H. S. Karthik , A. R. Usha Devi , J. Prabhu Tej , A. K. Rajagopal

Entropic uncertainty relations are powerful tools, especially in quantum cryptography. They typically bound the amount of uncertainty a third-party adversary may hold on a measurement outcome as a result of the measurement overlap. However,…

Quantum Physics · Physics 2023-05-18 Walter O. Krawec

B. Schumacher and M. Westmoreland have established a quantum analog of a well-known classical information theory result on a role of relative entropy as a measure of non-optimality in (classical) data compression. In this paper, we provide…

Quantum Physics · Physics 2008-08-08 Alexei Kaltchenko

Integral representations of quantum relative entropy, and of the directional second and higher order derivatives of von Neumann entropy, are established, and used to give simple proofs of fundamental, known data processing inequalities: the…

Quantum Physics · Physics 2023-09-13 Péter E. Frenkel

We describe some applications of quantum information theory to the analysis of quantum limits on measurement sensitivity. A measurement of a weak force acting on a quantum system is a determination of a classical parameter appearing in the…

Quantum Physics · Physics 2012-03-28 Andrew M. Childs , John Preskill , Joseph Renes

Noisy quantum channels may be used in many information carrying applications. We show that different applications may result in different channel capacities. Upper bounds on several of these capacities are proved. These bounds are based on…

Quantum Physics · Physics 2009-10-30 Howard Barnum , M. A. Nielsen , Benjamin Schumacher

The paper gives a systematic review of the basic ideas of (non-relativistic) quantum mechanics including all changes that result from previous work of the authors. This shows that the new theory is self-consistent and (in certain sense)…

Quantum Physics · Physics 2011-02-24 Petr Hajicek , Jiri Tolar

The one-shot classical capacity of a quantum channel quantifies the amount of classical information that can be transmitted through a single use of the channel such that the error probability is below a certain threshold. In this work, we…

Quantum Physics · Physics 2013-01-29 Ligong Wang , Renato Renner

This note will introduce some notation and definitions for information theoretic quantities in the context of quantum systems, such as (conditional) entropy and (conditional) mutual information. We will employ the natural C*-algebra…

Quantum Physics · Physics 2007-05-23 Andreas Winter

While the quantum mutual information is a fundamental measure of quantum information, it is only defined for spacelike-separated quantum systems. Such a limitation is not present in the theory of classical information, where the mutual…

Quantum Physics · Physics 2024-10-04 James Fullwood , Zhen Wu , Arthur J. Parzygnat , Vlatko Vedral

We determine the capacity of compound classical-quantum channels. As a consequence we obtain the capacity formula for the averaged classical-quantum channels. The capacity result for compound channels demonstrates, as in the classical…

Quantum Physics · Physics 2009-02-16 Igor Bjelakovic , Holger Boche

There are several inequalities in physics which limit how well we can process physical systems to achieve some intended goal, including the second law of thermodynamics, entropy bounds in quantum information theory, and the uncertainty…

Quantum Physics · Physics 2016-07-19 Francesco Buscemi , Siddhartha Das , Mark M. Wilde

We introduce ways to measure information storage in quantum systems, using a recently introduced computation-theoretic model that accounts for measurement effects. The first, the quantum excess entropy, quantifies the shared information…

Quantum Physics · Physics 2010-04-05 James P. Crutchfield , Karoline Wiesner

Quantum mechanics and information theory are among the most important scientific discoveries of the last century. Although these two areas initially developed separately it has emerged that they are in fact intimately related. In this…

Quantum Physics · Physics 2009-11-07 V. Vedral

We present the amounts of information, fidelity, and reversibility obtained by arbitrary quantum measurements on completely unknown states. These quantities are expressed as functions of the singular values of a measurement operator…

Quantum Physics · Physics 2016-02-05 Hiroaki Terashima

Classical messages can be sent via a noisy quantum channel in various ways, corresponding to various choices of signal states of the channel. Previous work by Holevo and by Schumacher and Westmoreland relates the capacity of the channel to…

Quantum Physics · Physics 2007-05-23 Benjamin Schumacher , Michael D. Westmoreland

The uncertainty principle is a fundamental principle in quantum physics. It implies that the measurement outcomes of two incompatible observables can not be predicted simultaneously. In quantum information theory, this principle can be…

Quantum Physics · Physics 2016-06-24 F. Adabi , S. Salimi , S. Haseli

We generalize recent work of Massar and Popescu dealing with the amount of classical data that is produced by a quantum measurement on a quantum state ensemble. In the previous work it was shown how spurious randomness generally contained…

Quantum Physics · Physics 2009-11-06 A. Winter , S. Massar