Eur. Phys. J. Special Topics 222, 601-608 (2013)
https://doi.org/10.1140/epjst/e2013-01865-4

Regular Article

Nonlinear normal modes and quanta in the β Fermi-Pasta-Ulam lattice

¹ Department of Physics, University of Pune, Pune P411007, India
² Nuclear Physics Division, Bhabha Atomic Research Centre, Mumbai 400085, India
³ Present address: Nuclear Physics Division, Bhabha Atomic Research Centre, Mumbai 400085, India

Received: 22 March 2013
Revised: 3 May 2013
Published online: 11 July 2013

Abstract

We enumerate simple periodic orbits for the well-known Fermi-Pasta-Ulam (FPU) problem. Using these solutions as simple modes for the problem, we construct quantum solutions of the corresponding problem. These studies present a natural generalization of the concept of phonon in the nonlinear realm.