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Related papers: The von Neumann Entropy for Mixed States

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We investigate the average entropy of a subsystem within a global unitary orbit of a given mixed bipartite state in the finite-dimensional space. Without working out the closed-form expression of such average entropy for the mixed state…

Quantum Physics · Physics 2017-03-22 Lin Zhang , Hua Xiang

The von Neumann entropy and the subentropy of a mixed quantum state are upper and lower bounds, respectively, on the accessible information of any ensemble consistent with the given mixed state. Here we define and investigate a set of…

Quantum Physics · Physics 2007-05-23 Sarah R. Nichols , William K. Wootters

We provide a generalized treatment of uncertainties, von Neumann entropy, and squeezing in entangled bipartite pure state of two-level atoms. We observe that when the bipartite state is entangled, though the von Neumann entropy of the…

Quantum Physics · Physics 2025-06-04 Ram Narayan Deb

A large class of strongly correlated quantum systems can be described in certain large-N limits by quadratic in field actions along with self-consistency equations that determine the two-point functions. We use the replica approach and the…

Strongly Correlated Electrons · Physics 2024-02-20 Siqi Shao , Yashar Komijani

We ask the question whether entropy accumulates, in the sense that the operationally relevant total uncertainty about an $n$-partite system $A = (A_1, \ldots A_n)$ corresponds to the sum of the entropies of its parts $A_i$. The Asymptotic…

Quantum Physics · Physics 2022-10-05 Frederic Dupuis , Omar Fawzi , Renato Renner

The notion of conditional entropy is extended to noncomposite systems. The q-deformed entropic inequalities, which usually are associated with correlations of the subsystem degrees of freedom in bipartite systems, are found for the…

Quantum Physics · Physics 2019-02-12 Vladimir N. Chernega , Olga V. Man'ko , Vladimir I. Man'ko

Strong subadditivity of von Neumann entropy, proved in 1973 by Lieb and Ruskai, is a cornerstone of quantum coding theory. All other known inequalities for entropies of quantum systems may be derived from it. Here we prove a new inequality…

Quantum Physics · Physics 2007-05-23 Noah Linden , Andreas Winter

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 study the von Neumann entropy of the partial trace of a system of two two-level atoms (qubits) in a dispersive cavity where the atoms are interacting collectively with a single mode electromagnetic field in the cavity. We make a contrast…

Quantum Physics · Physics 2021-10-01 Ram Narayan Deb

The entanglement entropy (von Neumann entropy) has been used to characterize the complexity of many-body ground states in strongly correlated systems. In this paper, we try to establish a connection between the lower bound of the von…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 S. Ryu , Y. Hatsugai

Given the algebra of observables of a quantum system subject to selection rules, a state can be represented by different density matrices. As a result, different von Neumann entropies can be associated with the same state. Motivated by a…

Quantum Physics · Physics 2021-05-25 Paolo Facchi , Giovanni Gramegna , Arturo Konderak

We study the atom-field interaction when the field is in a mixture of coherent states. We show that in this case it is possible to calculate analytically the field entropy for times of the order of twice the collapse time. Such analytical…

Quantum Physics · Physics 2016-08-17 A. Zuniga-Segundo , R. Juarez-Amaro , O. Aguilar-Loreto , H. M. Moya-Cessa

We consider the von Neumann entropy of a thermal mixed state in quantum systems derived from mirror curves, where the kinetic terms are exponential functions of the momentum operators. Using the mathematical results on the asymptotics of…

High Energy Physics - Theory · Physics 2023-10-10 Min-xin Huang

Based on the recently introduced averaging procedure in phase space, a new type of entropy is defined on the von Neumann lattice. This quantity can be interpreted as a measure of uncertainty associated with simultaneous measurement of the…

Quantum Physics · Physics 2009-11-07 Sumiyoshi Abe , J. Zak

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

We show for a general pure entangled state of two two-level atoms, the von Neumann entropy of the partial traces can be directly measured from the magnitude of the mean spin vector of a single atom of the pair. We emphasize the fact that…

Quantum Physics · Physics 2020-06-02 Ram Narayan Deb

The dynamics of an entangled atomic system in a partial interaction with entangled cavity fields, characterizing an entanglement swapping, have been studied through the use of Von Neuman entropy. We consider the interaction via two-photon…

Quantum Physics · Physics 2015-05-18 Wen-Chao Qiang , W. B. Cardoso , Xin-Hui Zhang

In this article, we present quantum algorithms for estimating von Neumann entropy and Renyi entropy, which are crucial physical and information-theoretical properties of a given quantum state $\rho$. Although there have been existing works…

Quantum Physics · Physics 2025-02-12 Nhat A. Nghiem , Tzu-Chieh Wei

We show that the entropy production in small open systems coupled to environments made of extended baths is predominantly caused by the displacement of the environment from equilibrium rather than, as often assumed, the mutual information…

Statistical Mechanics · Physics 2019-11-19 Krzysztof Ptaszynski , Massimiliano Esposito

We consider information characteristics of single qudit state (spin j=9/2), such as von Neumann entropy, von Neumann mutual information. We review different mathematical properties of these information characteristics: subadditivity and…

Quantum Physics · Physics 2018-07-03 V. I. Manko , T. Sabyrgaliyev
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