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We investigate whether the presence or absence of correlations between subsystems of an N-partite quantum system is solely constrained by the non-negativity and monotonicity of mutual information. We argue that this relatively simple…

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

Consider an arbitrary local quantum field theory with a gap or an arbitrary gapless free theory. We consider states in such a theory, that describe two entangled particles localized in disjoint regions of space. We show that in such a…

Quantum Physics · Physics 2016-09-13 Swapnamay Mondal

A fluctuation theorem for the nonequilibrium entropy production in quantum phase space is derived, which enables the consistent thermodynamic description of arbitrary quantum systems, open and closed. The new treatment naturally generalizes…

Statistical Mechanics · Physics 2013-08-13 Sebastian Deffner

Quantum information-theoretic approach has been identified as a way to understand the foundations of quantum mechanics as early as 1950 due to Shannon. However there hasn't been enough advancement or rigorous development of the subject. In…

Quantum Physics · Physics 2018-07-04 Shubhayan Sarkar

We consider a many-body Hilbert space with a fixed global charge and show that the typical entanglement entropy of a subsystem, at the leading and subleading order in the thermodynamic limit, can be expressed in terms of a single quantity…

Quantum Physics · Physics 2026-04-30 Eugenio Bianchi , Pietro Donà , Erick Muiño

Control of open quantum dynamics is of great interest for realizing quantum technologies. Therefore, it is an important task to quantify and characterize the entropy for open quantum systems under decoherence. In this paper, we study the…

Quantum Physics · Physics 2024-05-21 Kohei Kobayashi

Starting from a many-body classical system governed by a trace-form entropy we derive, in the stochastic quantization picture, a family of non linear and non-Hermitian Schroedinger equations describing, in the mean filed approximation, a…

Statistical Mechanics · Physics 2007-05-23 A. M. Scarfone

When a quantum system is coupled to several heat baths at different temperatures, it eventually reaches a non-equilibrium steady state featuring stationary internal heat currents. These currents imply that entropy is continually being…

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

The von Neumann entropy of a generic quantum state is not unique unless the state can be uniquely decomposed as a sum of extremal or pure states. As pointed out to us by Sorkin, this happens if the GNS representation (of the algebra of…

High Energy Physics - Theory · Physics 2012-12-11 A. P. Balachandran , A. R. de Queiroz , S. Vaidya

A general and computable criterion for k-(in)separability in continuous multipartite quantum systems is presented. The criterion can be experimentally implemented with a finite and comparatively low number of local observables. We discuss…

Quantum Physics · Physics 2012-02-07 Andreas Gabriel , Marcus Huber , Sasa Radic , Beatrix C. Hiesmayr

The von Neumann entropy of a $k$-body reduced density matrix $\gamma_k$ quantifies the entanglement between $k$ quantum particles and the remaining ones. In this short paper, we rigorously prove general properties of this entanglement…

Quantum Physics · Physics 2024-12-17 Marius Lemm

It is argued that the partition of a quantum system into subsystems is dictated by the set of operationally accessible interactions and measurements. The emergence of a multi-partite tensor product structure of the state-space and the…

Quantum Physics · Physics 2011-04-29 Paolo Zanardi , Daniel Lidar , Seth Lloyd

By computing the local energy expectation values with respect to some local measurement basis we show that for any quantum system there are two fundamentally different contributions: changes in energy that do not alter the local von Neumann…

Quantum Physics · Physics 2008-08-04 Hendrik Weimer , Markus J. Henrich , Florian Rempp , Heiko Schröder , Günter Mahler

Bell suggested that a new perspective on quantum mechanics was needed. We propose a solution of the measurement problem based on a reconsideration of the nature of particles. The solution is presented with an idealized model involving…

History and Philosophy of Physics · Physics 2021-02-26 Raymond S. Mackintosh

We consider some basic problems associated with quantum mechanics of systems having a time-dependent Hilbert space. We provide a consistent treatment of these systems and address the possibility of describing them in terms of a…

Quantum Physics · Physics 2024-09-24 Ali Mostafazadeh

Within the unified framework of exploiting the relative entropy as a distance measure of quantum correlations, we make explicit the hierarchical structure of quantum coherence, quantum discord and quantum entanglement in multipartite…

Quantum Physics · Physics 2015-08-19 Yao Yao , Xing Xiao , Li Ge , C. P. Sun

For a closed bi-partite quantum system partitioned into system proper and environment we interprete the microcanonical and the canonical condition as constraints for the interaction between those two subsystems. In both cases the possible…

Quantum Physics · Physics 2009-11-07 J. Gemmer , G. Mahler

The thermodynamic entropy of an isolated system is given by its von Neumann entropy. Over the last few years, there is an intense activity to understand thermodynamic entropy from the principles of quantum mechanics. More specifically, is…

Quantum Physics · Physics 2016-07-19 S. Santhosh Kumar , S. Shankaranarayanan