skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Correlations between chaos in a perturbed sine-Gordon equation and a truncated model system

Journal Article · · SIAM Journal of Mathematical Analysis (Society for Industrial and Applied Mathematics); (United States)
DOI:https://doi.org/10.1137/0521083· OSTI ID:7140466
 [1];  [2]; ;  [3];  [4]
  1. Los Alamos National Labs., NM (United States)
  2. L.A.M.F. Technical Univ. of Denmark, Lyngby (Denmark)
  3. Ohio State Univ., Columbus, OH (United States). Dept. of Mathematics
  4. Univ. of Arizona, Tucson, AZ (United States)

The purpose of this paper is to present a first step toward providing coordinates and associated dynamics for low-dimensional attractors in nearly integrable partial differential equations (pdes), in particular, where the truncated system reflects salient geometric properties of the pde. This is achieved by correlating: (1) numerical results on the bifurcations to temporal chaos with spatial coherence of the damped, periodically forced sine-Gordon equation with periodic boundary conditions; (2) an interpretation of the spatial and temporal bifurcation structures of this perturbed integrable system with regard to the exact structure of the sine-Gordon phase space; (3) a model dynamical systems problem, which is itself a perturbed integrable Hamiltonian system, derived from the perturbed sine-Gordon equation by a finite mode Fourier truncation in the nonlinear Schroedinger limit; and (4) the bifurcations to chaos in the truncated phase space. In particular, a potential source of chaos in both the pde and the model ordinary differential equation systems is focused on: the existence of homoclinic orbits in the unperturbed integrable phase space and their continuation in the perturbed problem. The evidence presented here supports the thesis that the chaotic attractors of the weakly perturbed periodic sine-Gordon system consists of low-dimensional metastable attacking states together with intermediate states that are O(1) unstable and correspond to homoclinic states in the integrable phase space. It is surmised that the chaotic dynamics on these attractors is due to the perturbation of these homocline integrable configurations.

OSTI ID:
7140466
Journal Information:
SIAM Journal of Mathematical Analysis (Society for Industrial and Applied Mathematics); (United States), Vol. 21:6; ISSN 0036-1410
Country of Publication:
United States
Language:
English