Coherent Motions in the Fermi-Pasta-Ulam Model
نویسنده
چکیده
1. Models of coupled oscillators 2. Two main classes (a) Models with on-site potentials; e.g. Frenkel-Kontorova or discrete NLS (b) Models with only nearest neighbor coupling; e.g. FPU type models 3. Focus on: (a) localized oscillations (b) traveling waves 4. Numerical experiments of Kruskal and Zabusky and the discovery of solitons. 5. The formal approximation of the FPU model by the KdV equation 6. A general method of justifying approximations by modulation equations 7. Details of the approximation proof in the case of the FPU model. ∗The work of the author is supported in part by the NSF under grant number DMS-0405724
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