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Related papers: Entropy, von Neumann and the von Neumann entropy

200 papers

Entropy can signify different things: For instance, heat transfer in thermodynamics or a measure of information in data analysis. Many entropies have been introduced and it can be difficult to ascertain their different importance and…

Mathematical Physics · Physics 2025-07-10 Henrik Jeldtoft Jensen , Piergiulio Tempesta

Thermodynamics can be formulated in either of two approaches, the phenomenological approach, which refers to the macroscopic properties of systems, and the statistical approach, which describes systems in terms of their microscopic…

Quantum Physics · Physics 2019-05-01 Mirjam Weilenmann , Lea Krämer Gabriel , Philippe Faist , Renato Renner

Entropy is a quantity which is of great importance in physics and chemistry. The concept comes out of thermodynamics, proposed by Rudolf Clausius in his analysis of Carnot cycle and linked by Ludwig Boltzmann to the number of specific ways…

Popular Physics · Physics 2015-11-25 Amelia Carolina Sparavigna

A dynamical estimate is given for the Boltzmann entropy of the Universe, under the simplifying assumptions provided by Newtonian cosmology. We first model the cosmological fluid as the probability fluid of a quantum-mechanical system. Next,…

Quantum Physics · Physics 2023-07-19 D. Cabrera , P. Fernandez de Cordoba , J. M. Isidro

Entropy is one of the central quantities in thermodynamics, whose flow between two systems determines the statistics of energy transfers. In quantum systems entropy is non-linear in density matrix whose time evolution is cumbersome. Using…

Mesoscale and Nanoscale Physics · Physics 2019-12-06 Mohammad H. Ansari

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

Using convex Grothendieck fibrations, we characterize the von Neumann entropy as a functor from finite-dimensional non-commutative probability spaces and state-preserving *-homomorphisms to real numbers. Our axioms reproduce those of Baez,…

Quantum Physics · Physics 2022-03-22 Arthur J. Parzygnat

We normalize the combinatorial Laplacian of a graph by the degree sum, look at its eigenvalues as a probability distribution and then study its Shannon entropy. Equivalently, we represent a graph with a quantum mechanical state and study…

Disordered Systems and Neural Networks · Physics 2012-04-24 Filippo Passerini , Simone Severini

We introduce superdensity operators as a tool for analyzing quantum information in spacetime. Superdensity operators encode spacetime correlation functions in an operator framework, and support a natural generalization of Hilbert space…

Quantum Physics · Physics 2018-10-17 Jordan Cotler , Chao-Ming Jian , Xiao-Liang Qi , Frank Wilczek

This paper explores the fundamental relationship between the geometry of entanglement and von Neumann entropy, shedding light on the intricate nature of quantum correlations. We provide a comprehensive overview of entanglement, highlighting…

Quantum Physics · Physics 2024-06-03 Ramita Sarkar , Soumik Mahanti , Prasanta K. Panigrahi

Entropy is a very useful concept from physics that tries to explain how a system behaves from a point of view of the thermodynamics. However, there are two ways to explain entropy, and it depends on if we are studying a microsystem or a…

General Finance · Quantitative Finance 2024-07-02 Martin Pomares Calero

In order to undestand how the complex concept of entropy emerged,we propose a trip towards the past reviewing the works of Clausius, Boltzmann, Gibbs and Planck. In particular, since the Gibbs's work is not very well known, we present a…

History and Philosophy of Physics · Physics 2015-06-11 L. Benguigui

Entropy is a fundamental property of both classical and quantum systems, spanning myriad theoretical and practical applications in physics and computer science. We study the problem of obtaining estimates to within a multiplicative factor…

Quantum Physics · Physics 2021-11-23 Tom Gur , Min-Hsiu Hsieh , Sathyawageeswar Subramanian

The paper is devoted to the investigation of Segal's entropy in semifinite von Neumann algebras. The following questions are dealt with: semicontinuity, the 'ideal-like' structure of the linear span of the set of operators with finite…

Operator Algebras · Mathematics 2024-02-20 Andrzej Łuczak

This manuscript introduces a computationally efficient method to calculate the nonlinearity of a quantum feature map, as well as a method for determining whether a quantum feature map will have a high concentration of quantum states. The…

Quantum Physics · Physics 2025-10-31 Andrew Vlasic , Payal Solanki , Anh Pham

Von Neumann obtained the formula for the entropy of a quantum state by assuming the validity of the second law of thermodynamics in a thought experiment involving semipermeable membranes and an ideal gas of quantum-labeled particles.…

Quantum Physics · Physics 2022-08-03 Shintaro Minagawa , Hayato Arai , Francesco Buscemi

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 use of the von Neumann entropy in formulating the laws of thermodynamics has recently been challenged. It is associated with the average work whereas the work guaranteed to be extracted in any single run of an experiment is the more…

Quantum Physics · Physics 2015-07-13 Dario Egloff , Oscar C. O. Dahlsten , Renato Renner , Vlatko Vedral

We have presented first an axiomatic derivation of Boltzmann entropy on the basis of two axioms consistent with two basic properties of thermodynamic entropy. We have then studied the relationship between Boltzmann entropy and information…

General Physics · Physics 2007-12-22 C. G. Chakrabarti , Indranil Chakrabarty

Entropy-like functionals on operator algebras have been studied since the pioneering work of von Neumann, Umegaki, Lindblad, and Lieb. The most well-known are the von Neumann entropy $trace (\rho\log \rho)$ and a generalization of the…

Optimization and Control · Mathematics 2008-07-19 Tryphon T. Georgiou