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Related papers: Linear entropy in quantum phase space

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We review recent developments in the theory of quantum dynamics in ultra-cold atomic physics, including exact techniques, but focusing on methods based on phase-space mappings that are appli- cable when the complexity becomes exponentially…

The geometric entanglement entropy of a quantum field in the vacuum state is known to be divergent and, when regularized, to scale as the area of the boundary of the region. Here we introduce an operational definition of the entropy of the…

High Energy Physics - Theory · Physics 2019-04-10 Eugenio Bianchi , Alejandro Satz

We define an entropy for a quantum field theory by combining quantum fluctuations, scaling and the maximum entropy concept. This entropy has different behavior in asymptotically free and non--asymptotically free theories. We find that the…

High Energy Physics - Theory · Physics 2009-09-25 J. Perez-Mercader

Entropy and free-energy estimation are key in thermodynamic characterization of simulated systems ranging from spin models through polymers, colloids, protein structure, and drug-design. Current techniques suffer from being model specific,…

Statistical Mechanics · Physics 2019-10-30 Ram Avinery , Micha Kornreich , Roy Beck

In this review we first introduce the general methods to calculate the entanglement entropy for free fields, within the Euclidean and the real time formalisms. Then we describe the particular examples which have been worked out explicitly…

High Energy Physics - Theory · Physics 2009-12-08 H. Casini , M. Huerta

Counting problems such as determining how many bit strings satisfy a given Boolean logic formula are notoriously hard. In many cases, even getting an approximate count is difficult. Here we propose that entanglement, a common concept in…

Statistical Mechanics · Physics 2013-04-03 Claudio Chamon , Eduardo R. Mucciolo

After a brief introduction to the concept of entanglement in quantum systems, I apply these ideas to many-body systems and show that the von Neumann entropy is an effective way of characterising the entanglement between the degrees of…

Statistical Mechanics · Physics 2009-11-13 John Cardy

We revisit the relationship between quantum separability and the sign of the relative q-entropies of composite quantum systems. The q-entropies depend on the density matrix eigenvalues p_i through the quantity omega_q = sum_i p_i^q. Renyi's…

Quantum Physics · Physics 2016-09-08 J. Batle , A. R. Plastino , M. Casas , A. Plastino

Quantum entanglement is one essential element to characterize many-body quantum systems. However, the entanglement measures are mostly discussed in Hermitian systems. Here, we propose a natural extension of entanglement and R\'enyi…

Strongly Correlated Electrons · Physics 2022-06-15 Yi-Ting Tu , Yu-Chin Tzeng , Po-Yao Chang

Resonance states of a two-electron quantum dot are studied using a variational expansion with both real basis-set functions and complex scaling methods. The two-electron entanglement (linear entropy) is calculated as a function of the…

Quantum Physics · Physics 2010-04-29 Federico M. Pont , Omar Osenda , Pablo Serra , Julio H. Toloza

We generalize the concept of the Wehrl entropy of quantum states which gives a basis-independent measure of their localization in phase space. We discuss the minimal values and the typical values of these R{enyi-Wehrl entropies for pure…

Quantum Physics · Physics 2009-11-07 Sven Gnutzmann , Karol Zyczkowski

In this four-part prospectus, we first give a brief introduction to the motivation for studying entanglement entropy and some recent development. Then follows a summary of our recent work about entanglement entropy in states with…

Quantum Physics · Physics 2009-08-18 Wenxin Ding

In this paper we calculate the entanglement entropy of two coupled gapless systems in general spatial dimension d. The gapless systems can be either conformal field theories (CFT), or Fermi liquids. We assume the two systems are coupled…

Strongly Correlated Electrons · Physics 2015-05-27 Cenke Xu

We study the entanglement entropy of harmonic oscillators in noncommutative phase space. We propose a new definition of quantum R\'enyi entropy based on Wigner functions in noncommutative phase space. Using the R\'enyi entropy, we calculate…

Mathematical Physics · Physics 2019-08-12 Bing-Sheng Lin , Jian Xu , Tai-Hua Heng

The Shannon entropy, and related quantities such as mutual information, can be used to quantify uncertainty and relevance. However, in practice, it can be difficult to compute these quantities for arbitrary probability distributions,…

Computation · Statistics 2017-10-11 Brendon J. Brewer

The entanglement entropy of a distinguished region of a quantum many-body system reflects the entanglement present in its pure ground state. In this work, we establish scaling laws for this entanglement for critical quasi-free fermionic and…

Quantum Physics · Physics 2014-11-11 M. Cramer , J. Eisert , M. B. Plenio

We replace a Hamiltonian with a modular Hamiltonian in the spectral form factor and the level spacing distribution function. This study establishes a connection between quantities within Quantum Entanglement and Quantum Chaos. To have a…

High Energy Physics - Theory · Physics 2022-11-15 Chen-Te Ma , Chih-Hung Wu

It is well known that loss of information about a system, for some observer, leads to an increase in entropy as perceived by this observer. We use this to propose an alternative approach to decoherence in quantum field theory in which the…

High Energy Physics - Theory · Physics 2015-05-18 Jurjen F. Koksma , Tomislav Prokopec , Michael G. Schmidt

As previously demonstrated, the entropy production -- a key quantity characterizing the irreversibility of thermodynamic processes -- is related to generation of correlations between degrees of freedom of the system and its thermal…

Quantum Physics · Physics 2023-06-29 Krzysztof Ptaszynski , Massimiliano Esposito

It is shown how the phase-damping master equation, either in Markovian and nonMarkovian regimes, can be obtained as an averaged random unitary evolution. This, apart from offering a common mathematical setup for both regimes, enables us to…

Quantum Physics · Physics 2015-06-26 D. Salgado , J. L. Sanchez-Gomez