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51.
A dynamical equation for quantum information density (QID) in curved spacetime is presented. The related fluctuation of QID with quantum Einstein equation is also discussed, which reveals the measuring of the dynamical mutual information condition using a Gaussian quantum channel. 相似文献
52.
Photorefractive two-beam coupling equations with multiple spatial–temporal features: an SVD approach
We analyze the evolution of multi-feature two-beam coupling, wherein each beam contains several spatial–temporal features
(spatial patterns modulated by different signals), using a one-dimensional plane wave model to describe the evolution of paired
components. This general scenario is of interest for analyzing signal-processing applications of photorefractives, such as
source-separation by orthogonalization of source-modulated spatial patterns. We use singular-value decomposition (SVD) to
express each beam as a simple superposition of modes that are both temporally uncorrelated and spatially orthogonal. We find
a solution that is a natural matrix generalization of the scalar solution for simple two-beam coupling, and a test for its
validity: the two operators that give the spatial overlap associated with the temporal basis signals in the two beams must
commute. Equivalently, this means that the same set of signals must be modulating the SVD modes in the two beams. Then the
SVD modes are preserved in the two-beam coupling evolution, with only their amplitudes changing.
Dedicated to Prof. Dr. Eckard Kr?tzig on the occasion of his 60th birthday.
Received: 10 November 1998 / Revised version: 13 January 1999 / Published online: 7 April 1999 相似文献
53.
54.
It is believed that some stars have two or more convection zones in close proximity near to the stellar photosphere. These zones are separated by convectively stable regions that are relatively narrow. Due to the close proximity of these regions it is important to construct mathematical models to understand the transport and mixing of passive and dynamic quantities. One key quantity of interest is a magnetic field, a dynamic vector quantity, that can drastically alter the convectively driven flows, and have an important role in coupling the different layers. In this Letter we present the first investigation into the effect of an imposed magnetic field in such a geometry. We focus our attention on the effect of field strength and show that, while there are some similarities with results for magnetic field evolution in a single layer, new and interesting phenomena are also present in a three layer system. 相似文献
55.
A. Isar A. Sandulescu W. Scheid 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2000,12(1):3-10
By using the Lindblad theory for open quantum systems, an analytical expression of the tunneling probability through an inverted
parabola is obtained. This penetration probability depends on the environment coefficients. It is shown that the tunneling
probability increases with the dissipation and the temperature of the thermal bath.
Received 15 October 1999 and Received in final form 5 January 2000 相似文献
56.
Xavier Frank 《Physics letters. A》2008,372(40):6155-6160
We investigate the chaotic dynamics of a bubble chain rising in a polymeric fluid by the experimental temporary measurements, cognitive modelling and analytical analysis. The competition between the stress creation and the relaxation displays complex dynamical features and leads to chaos through a sequence of period doubling bifurcations. 相似文献
57.
Drago?-Victor Anghel 《Physics letters. A》2008,372(36):5745-5747
I show that fractional exclusion statistics is manifested in general interacting systems and I calculate the exclusion statistics parameters. Most importantly, I prove that the mutual exclusion statistics parameters are proportional to the dimension of the Hilbert space on which they act [D.V. Anghel, J. Phys. A: Math. Theor. 40 (2007) F1013]. 相似文献
58.
Ming B. Yu 《Physics letters. A》2008,372(15):2572-2577
In the time-dependent projection operator formalism, the influence of environment upon a nonequilibrium open system is analyzed and an entropy equation is derived. The entropy production rate is given in terms of correlation functions of fluctuations of random forces and interacting random forces and cast into the Volterra equation formalism. 相似文献
59.
The power spectrum analysis using the Lomb-Scargle false alarm probability statistic shows a clear separation between the average and fluctuating parts of the state density in embedded two-body random matrix ensembles with a mean-field for both fermion and boson systems as well as in the nuclear shell model. 相似文献
60.
K. Wang P. Donnadieu P. Garoche 《The European Physical Journal B - Condensed Matter and Complex Systems》2000,13(2):279-287
We report on grain growth and related structure change in single phased Al-Li-Cu quasicrystals. The icosahedral phase grains
have been investigated using scanning ion microscopy and transmission electron microscopy. Regular boundaries between large
grains have been observed both before and after high temperature annealing. The electron diffraction study shows that the
grain growth is accompanied by a reduction of the phason-strains. The orientation relation between grains sets the 2-fold
icosahedral axes parallel, and the coincidence of the planes depends on the phason strain-field. The effect of phason-strain
field on these boundaries is discussed. It is proposed that the phason strain elimination can play a role in the grain growth.
Received 1 February 1999 and Received in final form 12 May 1999 相似文献