Weak Chaos Detection in the Fermi-PASTA-Ulam-α System Using Q-Gaussian Statistics

  title={Weak Chaos Detection in the Fermi-PASTA-Ulam-$\alpha$ System Using Q-Gaussian Statistics},
  author={Chris G. Antonopoulos and Helen Christodoulidi},
  journal={Int. J. Bifurc. Chaos},
We study numerically statistical distributions of sums of orbit coordinates, viewed as independent random variables in the spirit of the Central Limit Theorem, in weakly chaotic regimes associated with the excitation of the first (k = 1) and last (k = N) linear normal modes of the Fermi–Pasta–Ulam-α system under fixed boundary conditions. We show that at low energies (E = 0.19), when k = 1 linear mode is excited, chaotic diffusion occurs characterized by distributions that are well approximated… 
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