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Logical entropy gives a measure, in the sense of measure theory, of the distinctions of a given partition of a set, an idea that can be naturally generalized to classical probability distributions. Here, we analyze how fundamental concepts…

Quantum Physics · Physics 2022-03-14 Boaz Tamir , Ismael L. Paiva , Zohar Schwartzman-Nowik , Eliahu Cohen

A $q$-deformed Weyl-Heisenberg algebra is used to define a deformed displacement operator giving rise to a naturally normalized nonlinear coherent states type. Robust maximally entangled deformed coherent states are studied and the effect…

Quantum Physics · Physics 2019-09-24 Mohamed Taha Rouabah , Noureddine Mebarki

In this letter, the number-phase entropic uncertainty relation and the number-phase Wigner function of generalized coherent states associated to a few solvable quantum systems with nondegenerate spectra are studied. We also investigate time…

Quantum Physics · Physics 2009-09-30 G. R. Honarasa , M. K. Tavassoly , M. Hatami

Entanglement is one of the pillars of quantum mechanics and quantum information processing, and as a result the quantumness of nonentangled states has typically been overlooked and unrecognized. We give a robust definition for the…

Quantum Physics · Physics 2007-05-23 Berry Groisman , Dan Kenigsberg , Tal Mor

Complexity in strongly correlated electron systems is analyzed by considering decoherence process between the localized state, |L> and the itinerant state, |I>. The coherent superposition state of a|I> + b|L> decoheres to the pointer states…

Strongly Correlated Electrons · Physics 2011-01-04 Byung Gyu Chae

We investigate the Weyl channels being covariant with respect to the maximum commutative group of unitary operators. This class includes the quantum depolarizing channel and the "two-Pauli" channel as well. Then, we show that our estimation…

Quantum Physics · Physics 2009-11-13 G. G. Amosov

We introduce a new notion of entropy for quantum states, called contextual entropy, and show how it unifies Shannon and von Neumann entropy. The main result is that from the knowledge of the contextual entropy of a quantum state of a…

Quantum Physics · Physics 2012-08-13 Carmen Maria Constantin , Andreas Doering

In a wide range of quantum gravity theories, quasiclassical geometries, which are solutions to the Einstein field equations approximately, are described by "coherent states." Here we propose a Hamiltonian formalism for gravitational…

General Relativity and Quantum Cosmology · Physics 2025-12-01 Sijia Wang , Achintya Sajeendran , Dong-han Yeom , Robert B. Mann , Joshua Foo

In a recent work, arXiv:2503.05884, we proposed a unified notion of nonclassicality that applies to arbitrary processes in quantum theory, including individual quantum states, measurements, channels, set of these, etc. This notion is…

Quantum Physics · Physics 2025-04-07 Yujie Zhang , Yìlè Yīng , David Schmid

We study the correlations of classical and quantum systems from the information theoretical points of view. We analyze a simple measure of correlations based on entropy (such measure was already investigated as the degree of entanglement by…

Quantum Physics · Physics 2012-09-13 Yuji Hirota , Dariusz Chruściński , Takashi Matsuoka , Masanori Ohya

The dynamical generation of entanglement in closed bipartite systems is investigated in the semiclassical regime. We consider a model of two particles, initially prepared in a product of coherent states, evolving in time according to a…

Quantum Physics · Physics 2015-05-19 A. D. Ribeiro , R. M. Angelo

The notion of semi-classical states is first sharpened by clarifying two issues that appear to have been overlooked in the literature. Systems with linear and quadratic constraints are then considered and the group averaging procedure is…

General Relativity and Quantum Cosmology · Physics 2014-11-17 Abhay Ashtekar , Luca Bombelli , Alejandro Corichi

The position and momentum space information entropies, of the ground state of the P\"oschl-Teller potential, are exactly evaluated and are found to satisfy the bound, obtained by Beckner, Bialynicki-Birula and Mycielski. These entropies for…

Quantum Physics · Physics 2009-11-10 Rajneesh Atre , Anil Kumar , C. Nagaraja Kumar , Prasanta K. Panigrahi

We construct a complete set of Wannier functions which are localized at both given positions and momenta. This allows us to introduce the quantum phase space, onto which a quantum pure state can be mapped unitarily. Using its probability…

Statistical Mechanics · Physics 2015-06-10 Xizhi Han , Biao Wu

Several important measures of quantum correlations of a state of a finite-dimensional composite system are defined as linear combinations of marginal entropies of this state. This paper is devoted to the infinite-dimensional generalizations…

Quantum Physics · Physics 2017-08-23 M. E. Shirokov

We study the contextuality of a three-level quantum system using classical conditional entropy of measurement outcomes. First, we analytically construct the minimal configuration of measurements required to reveal contextuality. Next, an…

Quantum Physics · Physics 2013-05-30 Pawel Kurzynski , Ravishankar Ramanathan , Dagomir Kaszlikowski

Special approximation technique for analysis of different characteristics of states of multipartite infinite-dimensional quantum systems is proposed and applied to study of the relative entropy of entanglement and its regularisation. We…

Quantum Physics · Physics 2024-01-11 M. E. Shirokov

As part of a wider study of coherent states in (loop) quantum gravity, we introduce a modification to the standard construction, based on the recently introduced (non-commutative) flux representation. The resulting quantum states have some…

General Relativity and Quantum Cosmology · Physics 2015-05-30 Daniele Oriti , Roberto Pereira , Lorenzo Sindoni

Quantum channels, also called quantum operations, are linear, trace preserving and completely positive transformations in the space of quantum states. Such operations describe discrete time evolution of an open quantum system interacting…

Quantum Physics · Physics 2011-10-04 Wojciech Roga

Unentangled pure states on a bipartite system are exactly the coherent states with respect to the group of local transformations. What aspects of the study of entanglement are applicable to generalized coherent states? Conversely, what can…

Quantum Physics · Physics 2009-11-07 H. Barnum , E. Knill , G. Ortiz , L. Viola