Corpus ID: 236447459

Effective stochastic model for chaos in the Fermi-Pasta-Ulam-Tsingou chain

  title={Effective stochastic model for chaos in the Fermi-Pasta-Ulam-Tsingou chain},
  author={Tomer Goldfriend},
Understanding the interplay between different wave excitations, such as phonons, localized solitons, and chaotic breathers, is crucial for developing coarse-grained descriptions of many-body, near-integrable systems. We treat the Fermi-Pasta-Ulam-Tsingou (FPUT) non-linear chain and show numerically that at short timescales, relevant to the maximal Lyapunov exponent, it can be modeled as a random perturbation of its integrable approximation— the Toda chain. At low energies, the Lyapunov… Expand

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