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Proof of Nishida's conjecture on anharmonic lattices

Bob Rink
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Abstract

We prove Nishida's 1971 conjecture stating that almost all low-energetic motions of the anharmonic Fermi-Pasta-Ulam lattice with fixed endpoints are quasi-periodic. The proof is based on the formal computations of Nishida, the KAM theorem, discrete symmetry considerations and an algebraic trick that considerably simplifies earlier results.

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Bob Rink. 2005-06-09. Proof of Nishida's conjecture on anharmonic lattices. https://doi.org/10.1007/s00220-005-1451-1

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