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Related papers: On a new definition of quantum entropy

200 papers

Von Neumann entropy rate for open quantum systems is, in general, written in terms of entropy production and entropy flow rates, encompassing the second law of thermodynamics. When the open-quantum-system evolution corresponds to a quantum…

Quantum Physics · Physics 2022-01-05 Fabricio Toscano , Gustavo M. Bosyk , Steeve Zozor , Mariela Portesi

The entropy shows an unavoidable tendency of disorder in thermostatistics according to the second thermodynamics law. This provides a minimization entropy principle for quantum thermostatistics with the von Neumann entropy and nonextensive…

Quantum Physics · Physics 2021-04-09 M. X. Luo , X. Wang

The example provided in the comment [arXiv:0803.2241] concerns a situation where the system is initially at negative temperature. It is known that in such cases the Law of Entropy Decrease holds. Nevertheless, this does not challenge the…

Quantum Physics · Physics 2008-04-09 Michele Campisi

Adiabaticity is a cornerstone of many promising approaches to quantum control, computing, and simulation. In practice, however, there is always a trade-off. Although the deleterious effects of noise can be diminished by running a control…

Quantum Physics · Physics 2025-06-23 Pavel Zhelnin , Lucas Johns , Carlos A. Argüelles

Applying the theory of self-adjoint extensions of Hermitian operators to Koopman von Neumann classical mechanics, the most general set of probability distributions is found for which entropy is conserved by Hamiltonian evolution. A new…

Statistical Mechanics · Physics 2019-06-24 Gerard McCaul , Alexander Pechen , Denys I. Bondar

The second law of thermodynamics for adiabatic operations -- constraints on state transitions in closed systems under external control -- is one of the fundamental principles of thermodynamics. On the other hand, it is recently established…

Statistical Mechanics · Physics 2026-02-09 Yuuya Chiba , Yasushi Yoneta , Ryusuke Hamazaki , Akira Shimizu

A colloquial interpretation of entropy is that it is the knowledge gained upon learning the outcome of a random experiment. Conditional entropy is then interpreted as the knowledge gained upon learning the outcome of one random experiment…

Quantum Physics · Physics 2024-11-20 Gilad Gour , Mark M. Wilde , Sarah Brandsen , Isabelle Jianing Geng

Quantum dynamics controlled by a time-dependent coupling constant are studied. It is proven that an energy eigenstate expectation value of work done by the system in a quench process cannot exceed the work in the corresponding quasi-static…

Statistical Mechanics · Physics 2020-09-04 C. Itoi , M. Amano

We improve on our version of the second law of thermodynamics as a deterministic theorem for quantum spin systems in two basic aspects. The first concerns the general statement of the second law: spontaneous changes in an adiabatically…

Quantum Physics · Physics 2026-04-14 Walter F. Wreszinski

We take the view that the standard von Neumann definition, in which the entropy $S^{vN}$ of a pure state is zero, is in evident conflict with the statement of the second law that the entropy of the universe $S_{univ}$ increases in…

Quantum Physics · Physics 2018-10-25 George L. Barnes , Phillip C. Lotshaw , Michael E. Kellman

Entropy increase is fundamentally related to the breaking of time-reversal symmetry. By adding the 'extra dimension' associated with thermodynamic forces, we extend that discrete symmetry to a continuous symmetry for the dynamical…

Statistical Mechanics · Physics 2025-04-28 Aaron Beyen , Christian Maes

We give a simple proof of the uncertainty principle with quantum side information, as in [Berta et al. Nature Physics 6, 659 (2010)], invoking the monotonicity of the relative entropy. Our proof shows that the entropic uncertainty principle…

Quantum Physics · Physics 2011-12-08 Patrick J. Coles , Li Yu , Michael Zwolak

It was first suggested by David Z. Albert that the existence of a real, physical non-unitary process (i.e., "collapse") at the quantum level would yield a complete explanation for the Second Law of Thermodynamics (i.e., the increase in…

Quantum Physics · Physics 2018-07-24 R. E. Kastner

We define the entropy operator as the negative of the logarithm of the density matrix, give a prescription for extracting its thermodynamically measurable part, and discuss its dynamics. For an isolated system we derive the first, second…

Statistical Mechanics · Physics 2016-07-06 E. Solano-Carrillo , A. J. Millis

The second law of thermodynamics in nonextensive statistical mechanics is discussed in the quantum regime. Making use of the convexity property of the generalized relative entropy associated with the Tsallis entropy indexed by q, Clausius'…

Statistical Mechanics · Physics 2009-11-10 Sumiyoshi Abe , A. K. Rajagopal

The entropy accumulation theorem states that the smooth min-entropy of an $n$-partite system $A = (A_1, \ldots, A_n)$ is lower-bounded by the sum of the von Neumann entropies of suitably chosen conditional states up to corrections that are…

Quantum Physics · Physics 2019-07-23 Frédéric Dupuis , Omar Fawzi

We derive a generalization of Ehrenfest theorem valid for open quantum systems. From this result, we identify three contributions to the evolution of expected values: i) the explicit time dependence of the observable, ii) the…

Quantum Physics · Physics 2025-02-27 Andrés Vallejo , Alejandro Romanelli , Virginia Feldman , Raúl Donangelo

We analyze the production of entropy along non-equilibrium processes in quantum systems coupled to generic environments. First, we show that the entropy production due to final measurements and the loss of correlations obeys a fluctuation…

Quantum Physics · Physics 2018-08-08 Gonzalo Manzano , Jordan M. Horowitz , Juan M. R. Parrondo

The second law of nonequilibrium thermodynamics within the open system paradigm (a small system coupled to one or multiple baths) is derived. This is done by showing positivity of entropy production for arbitrary Hamiltonian dynamics for a…

Statistical Mechanics · Physics 2020-08-28 Philipp Strasberg

The entropy of a thermally isolated system should not decrease after a quench or external driving. For a classical system following Hamiltonian dynamics, we show how this statement emerges for a large system in the sense that the extensive…

Statistical Mechanics · Physics 2020-12-24 Udo Seifert