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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

This thesis consolidates, improves and extends the smooth entropy framework for non-asymptotic information theory and cryptography. We investigate the conditional min- and max-entropy for quantum states, generalizations of classical R\'enyi…

Quantum Physics · Physics 2015-03-20 Marco Tomamichel

The entanglement entropy of a pure quantum state of a bipartite system $A \cup B$ is defined as the von Neumann entropy of the reduced density matrix obtained by tracing over one of the two parts. Critical ground states of local…

Strongly Correlated Electrons · Physics 2008-11-26 Eduardo Fradkin , Joel E. Moore

We consider a quantum spin system consisting of a finite subsystem connected to infinite reservoirs at different temperatures. In this setup we define nonequilibrium steady states and prove that the rate of entropy production in such states…

Mathematical Physics · Physics 2009-10-31 David Ruelle

Entropy is the distinguishing and most important concept of our efforts to understand and regularize our observations of a very large class of natural phenomena, and yet, it is one of the most contentious concepts of physics. In this…

Quantum Physics · Physics 2007-05-23 Elias P. Gyftopoulos

We review with a tutorial scope the information theory foundations of quantum statistical physics. Only a small proportion of the variables that characterize a system at the microscopic scale can be controlled, for both practical and…

Statistical Mechanics · Physics 2007-05-23 R. Balian

One of the most counterintuitive aspects of quantum theory is its claim that there is 'intrinsic' randomness in the physical world. Quantum information science has greatly progressed in the study of intrinsic, or secret, quantum randomness…

In this article, we explore properties of pseudo entropy [1] in quantum field theories and spin systems from several approaches. Pseudo entropy is a generalization of entanglement entropy such that it depends on both an initial and final…

High Energy Physics - Theory · Physics 2021-09-22 Ali Mollabashi , Noburo Shiba , Tadashi Takayanagi , Kotaro Tamaoka , Zixia Wei

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

In order to quantify entanglement between two parts of a quantum system, one of the most used estimator is the Von Neumann entropy. Unfortunately, computing this quantity for large interacting quantum spin systems remains an open issue.…

Strongly Correlated Electrons · Physics 2011-05-26 S. Capponi , F. Alet , M. Mambrini

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

We investigate the information extractable from measurement distributions of two non-commuting spin observables in a multi-well spin-1 Bose-Einstein condensate. We provide a variety of analytic and numerical evidence that suitably chosen…

We define correlational (von Neumann) entropy for an individual quantum state of a system whose time-independent hamiltonian contains random parameters and is treated as a member of a statistical ensemble. This entropy is representation…

chao-dyn · Physics 2013-01-16 Valentin V. Sokolov , B. Alex Brown , Vladimir Zelevinsky

Quantum mechanical entanglement is a resource for quantum computation, quantum teleportation, and quantum cryptography. The ability to quantify this resource correctly has thus become of great interest to those working in the field of…

Quantum Physics · Physics 2009-11-07 J. R. Gittings , A. J. Fisher

The entanglement entropy of a pure quantum state of a bipartite system is defined as the von Neumann entropy of the reduced density matrix obtained by tracing over one of the two parts. Critical ground states of local Hamiltonians in one…

Strongly Correlated Electrons · Physics 2016-09-08 Eduardo Fradkin

For a quantum state undergoing unitary Schr\"odinger time evolution, the von Neumann entropy is constant. Yet the second law of thermodynamics, and our experience, show that entropy increases with time. Ingarden introduced the quantum…

Quantum Physics · Physics 2019-07-03 Craig S. Lent

Treating Coulomb scattering of two free electrons in a stationary approach, we explore the momentum and spin entanglement created by the interaction. We show that a particular discretisation provides an estimate of the von Neumann entropy…

Quantum Physics · Physics 2018-12-14 Peter Schattschneider , Stefan Löffler , Herbert Gollisch , Roland Feder

Observations or measurements taken of a quantum system (a small number of fundamental particles) are inherently random. If the state of the system depends on unknown parameters, then the distribution of the outcome depends on these…

Statistics Theory · Mathematics 2007-06-13 Richard D. Gill

The use of coarse graining to connect physical and information theoretic entropies has recently been given a precise formulation in terms of ``observational entropy'', describing entropy for observers with respect to a measurement. Here we…

Quantum Physics · Physics 2025-10-14 Leonardo Rossetti , Stefano Mancini , Andreas Winter , Joseph Schindler

We investigate the uncertainty associated with a joint quantum measurement of two components of spin of a spin-1/2 particle and quantify this in terms of entropy. We consider two entropic quantities: the joint entropy and the sum of the…

Quantum Physics · Physics 2015-05-13 Thomas Brougham , Erika Andersson , Stephen M Barnett