English
Related papers

Related papers: A classical model for semiclassical state-counting

200 papers

We will argue in this paper that the type classification of v.Neumann algebras play an important role in a theory of quantum gravity and quantum space-time physics. We provide arguments that type $II_{\infty}$ and its representation as a…

General Relativity and Quantum Cosmology · Physics 2025-01-13 Manfred Requardt

We explore the relation between classical and quantum states in both open and closed (super)strings discussing the relevance of coherent states as a semiclassical approximation. For the closed string sector a gauge-fixing of the residual…

High Energy Physics - Theory · Physics 2008-11-26 Jose J. Blanco-Pillado , Alberto Iglesias , Warren Siegel

In this work, we address the question of the impossibility of certain single-letter formulas by exploiting the semi-algebraic nature of various entropy-constrained sets. The focus lies on studying the properties of the level sets of…

Mathematical Physics · Physics 2023-09-15 Vjosa Blakaj , Chokri Manai

Subentropy is an entropy-like quantity that arises in quantum information theory; for example, it provides a tight lower bound on the accessible information for pure state ensembles, dual to the von Neumann entropy upper bound in Holevo's…

Quantum Physics · Physics 2015-12-31 Nilanjana Datta , Tony Dorlas , Richard Jozsa , Fabio Benatti

We will give a new model for measurements of a quantum system such that the measuring apparatuses are described by a unital separable non-type I nuclear simple C$^*$-algebra equipped with certain unital endomorphisms and pure states. An…

Quantum Physics · Physics 2016-01-26 Akitaka Kishimoto

We prove a variety of new and refined uniform continuity bounds for entropies of both classical random variables on an infinite state space and of quantum states of infinite-dimensional systems. We obtain the first tight continuity estimate…

Quantum Physics · Physics 2024-11-20 Simon Becker , Nilanjana Datta , Michael G. Jabbour

In this paper we discuss the problem of splitting the total correlations for a bipartite quantum state described by the Von Neumann mutual information into classical and quantum parts. We propose a measure of the classical correlations as…

Quantum Physics · Physics 2009-11-07 S. Hamieh , J. Qi , D. Siminovitch , M. K. Ali

Developments in theoretical cosmology in the recent decades show a close connection with particle physics, quantum gravity and unified theories. Answers or hints to many fundamental questions in cosmology like the homogeneity and isotropy…

General Relativity and Quantum Cosmology · Physics 2007-05-23 B. L. Hu

We report on an "anti-Gleason" phenomenon in classical mechanics: in contrast with the quantum case, the algebra of classical observables can carry a non-linear quasi-state, a monotone functional which is linear on all subspaces generated…

Quantum Physics · Physics 2009-11-13 Michael Entov , Leonid Polterovich , Frol Zapolsky

"Nonfreeness" is the (negative of the) difference between the von Neumann entropies of a given many-fermion state and the free state that has the same 1-particle statistics. It also equals the relative entropy of the two states in question,…

Quantum Physics · Physics 2007-05-23 Alex D. Gottlieb , Norbert J. Mauser

In quantum statistical mechanics, equilibrium states have been shown to be the typical states for a system that is entangled with its environment, suggesting a possible identification between thermodynamic and von Neumann entropies. In this…

Quantum Physics · Physics 2017-06-28 Thibaut Josset

A unified conceptual foundation of classical and quantum physics is given, free of undefined terms. Ensembles are defined by extending the `probability via expectation' approach of Whittle to noncommuting quantities. This approach carries…

Quantum Physics · Physics 2007-05-23 Arnold Neumaier

The paper presents variational formulae for entropy-like functionals, including Segal and R\'enyi entropies, for normal states on semifinite von Neumann algebras. The considered functionals are of the form $\tau(f(h))$ where $\tau$ is a…

Operator Algebras · Mathematics 2025-10-10 Andrzej Łuczak , Hanna Podsędkowska , Rafał Wieczorek

We study the semiclassical Einstein field equations with a Klein-Gordon field in ultrastatic and static spacetimes. In both cases, the equations for the spacetime metric become constraint equations. In the ultrastatic case, the Hadamard…

General Relativity and Quantum Cosmology · Physics 2021-11-01 Benito A. Juárez-Aubry

A definition for the entanglement entropy in both Abelian and non-Abelian gauge theories has been given in the literature, based on an extended Hilbert space construction. The result can be expressed as a sum of two terms, a classical term…

High Energy Physics - Theory · Physics 2019-08-15 Upamanyu Moitra , Ronak M Soni , Sandip P. Trivedi

Let S be the von Neumann entropy of a finite ensemble E of pure quantum states. We show that S may be naturally viewed as a function of a set of geometrical volumes in Hilbert space defined by the states and that S is monotonically…

Quantum Physics · Physics 2009-11-10 Graeme Mitchison , Richard Jozsa

Despite conventional wisdom that spin-1/2 systems have no classical analog, we introduce a set of classical coupled oscillators with solutions that exactly map onto the dynamics of an unmeasured electron spin state in an arbitrary,…

Quantum Physics · Physics 2011-12-12 K. B. Wharton , R. A. Linck , C. H. Salazar-Lazaro

Entropy is a famous and well established concept in physics and engineering that can be used for explanation of basic fundamentals as well it finds applications in several areas, from quantum physics to astronomy, from network communication…

Quantum Physics · Physics 2020-01-03 R. V. Ramos

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

Large series of prime numbers can be superposed on a single quantum register and then analyzed in full parallelism. The construction of this Prime state is efficient, as it hinges on the use of a quantum version of any efficient primality…

Quantum Physics · Physics 2014-04-08 José Ignacio Latorre , Germán Sierra