共查询到20条相似文献,搜索用时 46 毫秒
1.
X. Waintal D. Weinmann J.-L. Pichard 《The European Physical Journal B - Condensed Matter and Complex Systems》1999,7(3):451-456
For two particles in a disordered chain of length L with on-site interaction U, a duality transformation maps the behavior at weak interaction onto the behavior at strong interaction. Around the fixed
point of this transformation, the interaction yields a maximum mixing of the one body states. When (the one particle localization length), this mixing results in weak chaos accompanied by multifractal wave functions and
critical spectral statistics, as in the one particle problem at the mobility edge or in certain pseudo-integrable billiards.
In one dimension, a local interaction can only yield this weak chaos but can never drive the two particle system to full chaos
with Wigner-Dyson statistics.
Received: 22 May 1998 / Received in final form: 24 August 1998 / Accepted: 4 September 1998 相似文献
2.
X. Waintal J.-L. Pichard 《The European Physical Journal B - Condensed Matter and Complex Systems》1998,1(1):117-121
For N interacting particles in a one dimensional random potential, we study the structure of the corresponding network in Hilbert
space. The states without interaction play the role of the “sites”. The hopping terms are induced by the interaction. When
the one body states are localized, we numerically find that the set of directly connected “sites” is multifractal. For the
case of two interacting particles, the fractal dimension associated to the second moment of the hopping term is shown to characterize
the Golden rule decay of the non interacting states and the enhancement factor of the localization length.
Received: 17 April 1998 / Accepted: 14 May 1998 相似文献
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G. Abramson J.L. Vega 《The European Physical Journal B - Condensed Matter and Complex Systems》1999,9(2):361-364
Multifractal critical phenomena with infinite-temperature critical point and with complex coexistence of the infinite and
finite temperature critical points are considered and it is shown that strange attractors generated by cascades of period-doubling
bifurcations (Feigenbaum scenario) as well as fields of velocity differences in fluid turbulence belong to the former subclass
of the multifractal critical phenomena, while the real traffic processes and real currency exchange processes belong to the
last (complex) subclass of the multifractal critical phenomena. Data obtained by different authors are used for this purpose.
Received 5 February 1999 相似文献
6.
W. Jeżewski 《The European Physical Journal B - Condensed Matter and Complex Systems》2001,19(1):133-138
Scaling properties of the Gibbs distribution of a finite-size one-dimensional Ising model are investigated as the thermodynamic
limit is approached. It is shown that, for each nonzero temperature, coarse-grained probabilities of the appearance of particular
energy levels display multiscaling with the scaling length ℓ = 1/M
n, where n denotes the number of spins and Mn is the total number of energy levels. Using the multifractal formalism, the probabilities are argued to reveal also multifractal
properties.
Received 10 July 2000 and Received in final form 6 November 2000 相似文献
7.
Y. Rouault 《The European Physical Journal B - Condensed Matter and Complex Systems》1998,4(3):321-324
A living polymer system is used to study the effect of concentration on a broad, polydisperse two-dimensional polymer system.
It is found that the mean squared end-to-end radius of a chain of L monomers does not decrease by following a simple power law of the concentration but by a function of the form . An origin for such a behaviour is proposed.
Received: 21 November 1997 / Received in final form: 21 April 1998 / Accepted: 24 April 1998 相似文献
8.
N. Vandewalle M. Ausloos P. Boveroux A. Minguet 《The European Physical Journal B - Condensed Matter and Complex Systems》1998,4(2):139-141
From the analysis of (closing value) stock market index like the Dow Jones Industrial average and the S&P500 it is possible
to observe the precursor of a so-called crash. This is shown on the Oct. 1987 and Oct. 1997 cases. The data analysis indicates
that the index divergence has followed twice a “universal” behavior, i.e. a logarithmic dependence, superposed on a well defined oscillation pattern. The prediction of the crash date is remarkable
and can be done two months in advance. In the spirit of phase transition phenomena, the economic index is said to be analogous
to a signal signature found in a two dimensional fluid of vortices.
Received: 23 March 1998 / Revised and Accepted: 23 April 1998 相似文献
9.
D. Chowdhury A. Pasupathy S. Sinha 《The European Physical Journal B - Condensed Matter and Complex Systems》1998,5(3):781-786
In the Nagel-Schreckenberg model of vehicular traffic on single-lane highways vehicles are modelled as particles which hop
forward from one site to another on a one dimensional lattice and the inter-particle interactions mimic the manner in which
the real vehicles influence each other's motion. In this model the number of empty lattice sites in front of a particle is
taken to be a measure of the corresponding distance-headway (DH). The time-headway (TH) is defined as the time interval between the departures (or arrivals) of two successive particles recorded by a detector
placed at a fixed position on the model highway. We investigate the effects of spatial inhomogeneities of the highway (static
hindrances) on the DH and TH distributions in the steady-state of this model.
Received: 2 March 1988 / Revised: 13 April 1998 / Accepted: 17 April 1998 相似文献
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In the present paper we study the multifractal spectrum of local entropies. We obtain results, similar to those of the multifractal
analysis of pointwise dimensions, but under much weaker assumptions on the dynamical systems. We assume our dynamical system
to be defined by an expansive homeomorphism with the specification property. We establish the variational relation between
the multifractal spectrum and other thermodynamical characteristics of the dynamical system, including the spectrum of correlation
entropies.
Received: 22 September 1998 / Accepted: 11 December 1998 相似文献
12.
E. Nogueira Jr. R.F.S. Andrade S. Coutinho 《The European Physical Journal B - Condensed Matter and Complex Systems》2001,23(3):373-382
The role of the geometric fluctuations on the multifractal properties of the local magnetization of aperiodic ferromagnetic
Ising models on hierarchical lattices is investigated. The geometric fluctuations are introduced by generalized Fibonacci
sequences. The local magnetization is evaluated via an exact recurrent procedure encompassing real space renormalization group decimation. The symmetries of the local magnetization
patterns induced by the aperiodic couplings is found to be strongly (weakly) different, with respect to the ones of the corresponding
homogeneous systems, when the geometric fluctuations are relevant (irrelevant) to change the critical properties of the system.
At the criticality, the measure defined by the local magnetization is found to exhibit a non-trivial F(α) spectra being shifted to higher values of α when relevant geometric fluctuations are considered. The critical exponents
are found to be related with some special points of the F(α) function and agree with previous results obtained by the quite distinct transfer matrix approach.
Received 2 April 2001 and Received in final form 14 August 2001 相似文献
13.
B.A. Berg U.H.E. Hansmann 《The European Physical Journal B - Condensed Matter and Complex Systems》1998,6(3):395-398
Applied to statistical physics models, the random cost algorithm enforces a Random Walk (RW) in energy (or possibly other
thermodynamic quantities). The dynamics of this procedure is distinct from fixed weight updates. The probability for a configuration
to be sampled depends on a number of unusual quantities, which are explained in this paper. This has been overlooked in recent
literature, where the method is advertised for the calculation of canonical expectation values. We illustrate these points
for the 2d Ising model. In addition, we prove a previously conjectured equation which relates microcanonical expectation values to the
spectral density.
Received: 13 May 1998 / Received in final form and Accepted: 26 May 1998 相似文献
14.
A. Bershadskii 《The European Physical Journal B - Condensed Matter and Complex Systems》1999,9(4):691-693
It is shown that multifractal properties of some random and disordered systems can be simulated using thermodynamics of a
generalized ideal monoatomic gas in a fractal phase space.
Received 25 November 1998 and Received in final form 16 December 1998 相似文献
15.
Numerical data for the distribution of citations are examined for: (i) papers published in 1981 in journals which are catalogued
by the Institute for Scientific Information (783,339 papers) and (ii) 20 years of publications in Physical Review D, vols.
11-50 (24,296 papers). A Zipf plot of the number of citations to a given paper versus its citation rank appears to be consistent with a power-law dependence for leading rank papers, with exponent close to -1/2.
This, in turn, suggests that the number of papers with x citations, N(x), has a large-x power law decay , with .
Received: 12 May 1998 / Accepted: 12 May 1998 相似文献
16.
T.T. Truong 《The European Physical Journal B - Condensed Matter and Complex Systems》1998,5(3):697-703
We point out the existence of an alternative algebraic structure in Yang-Baxter algebra with trigonometric R-matrix, which appears to be the generalization of the Yangian in Yang-Baxter algebras with rational R-matrix and which is described most naturally by q-commutators. Some properties are presented, in particular in the case of the well-known symmetric six-vertex model.
Received: 13 February 1998 / Revised: 16 March 1998 / Accepted: 17 April 1998 相似文献
17.
A.B.C. Patzer C. Chang E. Sedlmayr D. Sülzle 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》1999,6(1):57-62
We present ab initio thermodynamic properties for seven different geometric isomers of molecular Al2O3 over a wide temperature range. The rigid rotator-harmonic oscillator approximation is used to calculate the partition function
as it is generally applied in thermodynamic studies of polyatomic molecules. The molecular data employed in setting up the
partition functions are taken from the theoretical results of ab initio MP2/6-31G(d) calculations. An analysis of the effects of the various contributions is made. The resulting thermodynamic functions
of Al2O3 are consistent with the JANAF thermochemical data compilation. Some thermochemical implications are discussed.
Received: 9 September 1998 / Received in final form: 2 October 1998 相似文献
18.
A. Arnéodo J.-F. Muzy D. Sornette 《The European Physical Journal B - Condensed Matter and Complex Systems》1998,2(2):277-282
We use wavelets to decompose the volatility (standard deviation) of intraday (S&P500) return data across scales. We show that
when investigating two-point correlation functions of the volatility logarithms across different time scales, one reveals
the existence of a causal information cascade from large scales (i.e. small frequencies) to fine scales. We quantify and visualize the information flux across scales. We provide a possible interpretation
of our findings in terms of market dynamics.
Received: 9 January 1998 / Received in final form and accepted: 13
January 1998 相似文献
19.
A wavelet-based method for multifractal image analysis. I. Methodology and test applications on isotropic and anisotropic random rough surfaces 总被引:3,自引:0,他引:3
A. Arnéodo N. Decoster S.G. Roux 《The European Physical Journal B - Condensed Matter and Complex Systems》2000,15(3):567-600
We generalize the so-called wavelet transform modulus maxima (WTMM) method to multifractal image analysis. We show that the
implementation of this method provides very efficient numerical techniques to characterize statistically the roughness fluctuations
of fractal surfaces. We emphasize the wide range of potential applications of this wavelet-based image processing method in
fundamental as well as applied sciences. This paper is the first one of a series of three articles. It is mainly devoted to
the methodology and to test applications on random self-affine surfaces (e.g., isotropic fractional Brownian surfaces and anisotropic monofractal rough surfaces). Besides its ability to characterize
point-wise regularity, the WTMM method is definitely a multiscale edge detection method which can be equally used for pattern
recognition, detection of contours and image denoising. Paper II (N. Decoster, S.G. Roux, A. Arnéodo, to be published in Eur.
Phys. J. B 15 (2000)) will be devoted to some applications of the WTMM method to synthetic multifractal rough surfaces. In paper III (S.G.
Roux, A. Arnéodo, N. Decoster, to be published in Eur. Phys. J. 15 (2000)), we will report the results of a comparative experimental analysis of high-resolution satellite images of cloudy
scenes.
Received 8 July 1999 相似文献
20.
A. Bershadskii 《The European Physical Journal B - Condensed Matter and Complex Systems》1998,3(2):141-142
It is shown that quasi Bernoulli fluctuations, which appear at a morphological phase transition, can be considered as a statistical
basis for multifractal processes with constant multifractal specific heat in a wide class of random and disordered systems.
This class contains at least following processes: percolation, diffusion-limited aggregation and corrosion, Lorenz like attractors,
and mesoscopic systems with Anderson transition.
Received: 14 April 1998 / Revised and Accepted: 20 April 1998 相似文献