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Related papers: Entropy of a quantum channel

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The proper definition of entropy is fundamental to the relationship between statistical mechanics and thermodynamics. It also plays a major role in the recent debate about the validity of the concept of negative temperature. In this paper,…

Statistical Mechanics · Physics 2015-11-18 Robert H. Swendsen

We describe analytical properties of the average output entropy of a quantum channel as a function of a pair (channel, input ensemble). In particular, tight semicontinuity bounds for this function with the rank/energy constraints are…

Quantum Physics · Physics 2024-04-12 M. E. Shirokov

A method of representing probabilistic aspects of quantum systems is introduced by means of a density function on the space of pure quantum states. In particular, a maximum entropy argument allows us to obtain a natural density function…

Quantum Physics · Physics 2015-06-26 D. C. Brody , L. P. Hughston

A new interpretation of entanglement entropy is proposed: entanglement entropy of a pure state with respect to a division of a Hilbert space into two subspaces 1 and 2 is an amount of information, which can be transmitted through 1 and 2…

General Relativity and Quantum Cosmology · Physics 2016-08-25 Shinji Mukohyama

We introduce an quantum entropy for bimodule quantum channels on finite von Neumann algebras, generalizing the remarkable Pimsner-Popa entropy. The relative entropy for Fourier multipliers of bimodule quantum channels establishes an upper…

Operator Algebras · Mathematics 2024-01-01 Zishuo Zhao

In this work we prove that the possibility of superactivation of quantum channel capacities is determined by the mathematical properties of the quantum relative entropy function. Before our work this fundamental and purely mathematical…

Quantum Physics · Physics 2012-06-26 Laszlo Gyongyosi , Sandor Imre

We define classical-quantum multiway channels for transmission of classical information, after recent work by Allahverdyan and Saakian. Bounds on the capacity region are derived in a uniform way, which are analogous to the classically known…

Quantum Physics · Physics 2016-11-15 Andreas Winter

The von Neumann entanglement entropy is a useful measure to characterize a quantum phase transition. We investigate the non-analyticity of this entropy at disorder-dominated quantum phase transitions in non-interacting electronic systems.…

Mesoscale and Nanoscale Physics · Physics 2008-01-27 X. Jia , A. R. Subramaniam , I. A. Gruzberg , S. Chakravarty

The quantum version of a fundamental entropic data-processing inequality is presented. It establishes a lower bound for the entropy that can be generated in the output channels of a scattering process, which involves a collection of…

Quantum Physics · Physics 2015-03-30 Giacomo De Palma , Andrea Mari , Seth Lloyd , Vittorio Giovannetti

The correspondence principle plays a fundamental role in quantum mechanics, which naturally leads us to inquire whether it is possible to find or determine close classical analogs of quantum states in phase space -- a common meeting point…

Quantum Physics · Physics 2022-01-28 A. S. Sanz

The aim of this work is to introduce the entanglement entropy of real and virtual excitations of fermion and photon fields. By rewriting the generating functional of quantum electrodynamics theory as an inner product between quantum…

High Energy Physics - Theory · Physics 2018-05-23 Juan Sebastian Ardenghi

Statistical correlations that can be generated across the nodes in a quantum network depend crucially on its topology. However, this topological information might not be known a priori, or it may need to be verified. In this paper, we…

Quantum Physics · Physics 2024-01-08 Daniel T. Chen , Brian Doolittle , Jeffrey M. Larson , Zain H. Saleem , Eric Chitambar

Currently, 'time' does not play any essential role in quantum information theory. In this sense, quantum information theory is underdeveloped similarly to how quantum physics was underdeveloped before Erwin Schrodinger introduced his famous…

Mesoscale and Nanoscale Physics · Physics 2019-09-04 Mohammad H. Ansari , Alwin van Steensel , Yuli V. Nazarov

We study quantum channels with respect to their image, i.e., the image of the set of density operators under the action of the channel. We first characterize the set of quantum channels having polytopic images and show that additivity of…

Quantum Physics · Physics 2015-10-15 Motohisa Fukuda , Ion Nechita , Michael M. Wolf

We compare the entropy-energy inequality and the von Neumann entropic inequality for three level atom implemented on superconducting circuits with Josephson junction. The positivity of entropy and energy relations for the qutrit system are…

Quantum Physics · Physics 2016-08-08 V. I. Man'ko , L. A. Markovich

We compare the thermodynamic entropy of a quantum Brownian oscillator derived from the partition function of the subsystem with the von Neumann entropy of its reduced density matrix. At low temperatures we find deviations between these two…

Quantum Physics · Physics 2009-11-13 Christian Hoerhammer , Helmut Buettner

We introduce a new notion of entropy for quantum states, called contextual entropy, and show how it unifies Shannon and von Neumann entropy. The main result is that from the knowledge of the contextual entropy of a quantum state of a…

Quantum Physics · Physics 2012-08-13 Carmen Maria Constantin , Andreas Doering

Entanglement is a special feature of the quantum world that reflects the existence of subtle, often non-local, correlations between local degrees of freedom. In topological theories such non-local correlations can be given a very intuitive…

High Energy Physics - Theory · Physics 2020-01-31 D. Melnikov , A. Mironov , S. Mironov , A. Morozov , An. Morozov

The notion of a partition on a set is mathematically dual to the notion of a subset of a set, so there is a logic of partitions dual to Boole's logic of subsets (Boolean subset logic is usually mis-specified as the special case of…

Quantum Physics · Physics 2018-03-06 David Ellerman

The relative entropy between quantum states quantifies their distinguishability. The estimation of certain relative entropies has been investigated in the literature, e.g., the von Neumann relative entropy and sandwiched R\'enyi relative…

Quantum Physics · Physics 2026-02-24 Jinge Bao , Minbo Gao , Qisheng Wang