English
Related papers

Related papers: Entropy fluctuations as a mixedness quantifier

200 papers

We revisit generalized entropic formulations of the uncertainty principle for an arbitrary pair of quantum observables in two-dimensional Hilbert space. R\'enyi entropy is used as uncertainty measure associated with the distribution…

Quantum Physics · Physics 2014-06-23 Steeve Zozor , Gustavo Martín Bosyk , Mariela Portesi

Entropic uncertainty relations, based on sums of entropies of probability distributions arising from different measurements on a given pure state, can be seen as a generalization of the Heisenberg uncertainty relation that is in many cases…

Quantum Physics · Physics 2007-05-23 Adam Azarchs

We consider shift spaces in which elements of the alphabet may overlap nontransitively. We define a notion of entropy for such spaces, give several techniques for computing lower bounds for it, and show that it is equal to a limit of…

Dynamical Systems · Mathematics 2010-11-16 Fabio Drucker , David Richeson , Jim Wiseman

Heisenberg's uncertainty principle has recently led to general measurement uncertainty relations for quantum systems: incompatible observables can be measured jointly or in sequence only with some unavoidable approximation, which can be…

Quantum Physics · Physics 2017-06-27 Alberto Barchielli , Matteo Gregoratti , Alessandro Toigo

After a brief historical review of ergodicity and mixing in dynamics, particularly in quantum dynamics, we introduce definitions of quantum ergodicity and mixing using the structure of the system's energy levels and spacings. Our…

Statistical Mechanics · Physics 2016-09-07 Dongliang Zhang , H. T. Quan , Biao Wu

We investigate the problem of the entropy of the mixture of sources. There is given an estimation of the entropy and entropy dimension of convex combination of measures. The proof is based on our alternative definition of the entropy based…

Information Theory · Computer Science 2011-10-31 Marek Smieja , Jacek Tabor

The entanglement entropy of a subsystem of a quantum system is expressed, in the replica approach, through analytic continuation with respect to n of the trace of the n-th power of the reduced density matrix. This trace can be thought of as…

High Energy Physics - Theory · Physics 2008-12-18 Michele Caraglio , Ferdinando Gliozzi

Various notions of fluctuations exist depending on the way one chooses to measure them. We discuss two extreme cases (continuous measurement versus long inter-measurement times) and we see their relation with entropy production and with…

Statistical Mechanics · Physics 2009-11-05 C. Maes , K. Netocny

A relationship between a recently introduced multipartite entanglement measure, state mixedness, and spin-flip symmetry is established for any finite number of qubits. It is also shown that, within those classes of states invariant under…

Quantum Physics · Physics 2009-11-10 Gregg Jaeger , Alexander V. Sergienko , Bahaa E. A. Saleh , Malvin C. Teich

Gravitational and hydrodynamical perturbations are analysed in a relativistic plasma containing a mixture of interacting fluids characterized by a non-negligible bulk viscosity coefficient. The energy-momentum transfer between the…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Massimo Giovannini

The trace over the degrees of freedom located in a subset of the space transforms the vacuum state into a mixed density matrix with non zero entropy. This is usually called entanglement entropy, and it is known to be divergent in quantum…

High Energy Physics - Theory · Physics 2009-11-10 H. Casini , M. Huerta

By introducing Hilbert space and operators, we show how probabilities, approximations and entropy encoding from signal and image processing allow precise formulas and quantitative estimates. Our main results yield orthogonal bases which…

Mathematical Physics · Physics 2009-11-13 Palle E. T. Jorgensen , Myung-Sin Song

We evoke situations where large fluctuations in the entropy are induced, our main example being a spacetime containing a potential black hole whose formation depends on the outcome of a quantum mechanical event. We argue that the…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Rafael Sorkin , Daniel Sudarsky

Kempf et al. in Ref. [1] have formulated a Hilbert space representation of quantum mechanics with a minimal measurable length. Recently it has been revealed, in the context of doubly special relativity, that a test particles' momentum…

High Energy Physics - Theory · Physics 2015-06-04 Kourosh Nozari , Amir Etemadi

We revisit the classical problem of inverting dimension-reducing linear mappings using the maximum entropy (MaxEnt) criterion. In the literature, solutions are problem-dependent, inconsistent, and use different entropy measures. We propose…

Machine Learning · Computer Science 2024-07-22 Paul M Baggenstoss

We investigate in detail the behavior of the bipartite fluctuations of particle number $\hat{N}$ and spin $\hat{S}^z$ in many-body quantum systems, focusing on systems where such U(1) charges are both conserved and fluctuate within…

Mesoscale and Nanoscale Physics · Physics 2012-01-10 H. Francis Song , Stephan Rachel , Christian Flindt , Israel Klich , Nicolas Laflorencie , Karyn Le Hur

The block entanglement entropy and fluctuations are investigated in one dimension in finite size correlated electron systems using the Gutzwiller wave function as a prototype correlated electron state. Entanglement entropy shows logarithmic…

Strongly Correlated Electrons · Physics 2014-07-07 Archak Purkayastha , V. Subrahmanyam

We present observable upper bounds of squared concurrence, which are the dual inequalities of the observable lower bounds introduced in [F. Mintert and A. Buchleitner, Phys. Rev. Lett. 98, 140505 (2007)] and [L. Aolita, A. Buchleitner and…

Quantum Physics · Physics 2009-11-13 Cheng-Jie Zhang , Yan-Xiao Gong , Yong-Sheng Zhang , Guang-Can Guo

A maximum entropy-based framework is presented for the synthesis of projections from multiple Earth climate models. This identifies the most representative (most probable) model from a set of climate models -- as defined by specified…

Geophysics · Physics 2017-08-23 Robert K. Niven

We report the creation of a wide range of quantum states with controllable degrees of entanglement and entropy using an optical two-qubit source based on spontaneous parametric downconversion. The states are characterised using measures of…

Quantum Physics · Physics 2009-11-07 A. G. White , D. F. V. James , W. J. Munro , P. G. Kwiat