The Fermi-Pasta-Ulam paradox, Anderson Localization problem and the the generalized diffusion approach
نویسنده
چکیده
The goal of this paper is two-fold. First, based on the interpretation of a quantum tight-binding model in terms of a classical Hamiltonian map, we consider the Anderson localization (AL) problem as the Fermi-Pasta-Ulam (FPU) effect in a modified dynamical system containing both stable and unstable (inverted) modes. Delocalized states in the AL are analogous to the stable quasi-periodic motion in FPU; whereas localized states are analogous to thermalization, respectively. The second aim is to use the classical Hamilton map for a simplified derivation of exact equations for the localization operator H(z). The letter was presented earlier [J.Phys.: Condens. Matter 14 (2002) 13777] treating the AL as a generalized diffusion in a dynamical system. We demonstrate that counter-intuitive results of our studies of the AL are similar to the FPU counter-intuitivity. PACS numbers: 05.40.-a , 05.45.-a , 72.15.Rn ∗Electronic address: [email protected]
منابع مشابه
q-Breathers and the Fermi-Pasta-Ulam problem.
The Fermi-Pasta-Ulam (FPU) paradox consists of the non-equipartition of energy among normal modes of a weakly anharmonic atomic chain model. In the harmonic limit each normal mode corresponds to a periodic orbit in phase space and is characterized by its wave number q. We continue normal modes from the harmonic limit into the FPU parameter regime and obtain persistence of these periodic orbits,...
متن کاملDetecting chaos, determining the dimensions of tori and predicting slow diffusion in Fermi–Pasta–Ulam lattices by the Generalized Alignment Index method
The recently introduced GALI method is used for rapidly detecting chaos, determining the dimensionality of regular motion and predicting slow diffusion in multi–dimensional Hamiltonian systems. We propose an efficient computation of the GALIk indices, which represent volume elements of k randomly chosen deviation vectors from a given orbit, based on the Singular Value Decomposition (SVD) algori...
متن کاملTHE FERMI-PASTA-ULAM LATTICE Background The Fermi-Pasta-Ulam lattice is named after the experiments
The Fermi-Pasta-Ulam lattice is named after the experiments performed by Enrico Fermi, John Pasta, and Stanislaw Ulam in 1954-5 on the Los Alamos MANIAC computer, one of the first electronic computers. As reported in Ulam’s autobiography [Uh], Fermi immediately suggested using the new machine for theoretical work, and it was decided to start by studying the vibrations of a string under the infl...
متن کاملFrom Fermi-pasta-ulam Problem to Galaxies: the Quest for Relaxation
The major problem posed by the Fermi-Pasta-Ulam work was the relaxation (thermalization) of a many-body system. We review two approaches to this problem, the ergodic theory and Langevin (stochastic) equation ones, which have been applied for the description of statistical mechanics of stellar systems. Among the particular problems that we consider, are 1-dimensional long-range interacting syste...
متن کاملThe development of truncated inviscid turbulence and the Fermi-Pasta-Ulam problem.
A study was made of the possible similarity between the development of truncated, inviscid turbulence and the Fermi-Pasta-Ulam (FPU) problem. For the case of a constant time scale, which resembles the FPU problem, a significant increase in the time to achieve equipartition was found when the initial energy was decreased. At first a few modes were generated and only rather late in the spectral d...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 2008