Abstract
The numerical computation of the largest Lyapunov exponent of a system composed by a heavy impurity embedded in a chain of anharmonic nearest-neighbor Fermi-Pasta-Ulam oscillators for various values of the impurity mass M was discussed. It was observed that the complete Lyapunov spectrum does not depend significantly on the impurity mass M. It was suggested that impurity does not contribute significantly to the dynamical instability (Chaos) of the chain and can be considered as a probe for the dynamics of the system to which the impurity was coupled. It was shown that the Kolmogorov-Sinai entropy of the chain has a crossover from weak to strong Chaos at the same value of the energy density as the crossover value of the largest Lyapunov exponent.
| Original language | English |
|---|---|
| Article number | 056204 |
| Pages (from-to) | 056204-1-056204-5 |
| Journal | Physical Review E - Statistical, Nonlinear, and Soft Matter Physics |
| Volume | 69 |
| Issue number | 5 1 |
| State | Published - May 2004 |
| Externally published | Yes |