We study the asymptotic dynamics of breathers in finite Fermi-Pasta-Ulam chains at zero and non-zero temperatures. While such breathers are essentially stationary and very long-lived at zero temperature, thermal fluctuations tend to lead to breather motion and more rapid decay.
@article{arxiv.cond-mat/0205323,
title = {Asymptotic Dynamics of Breathers in Fermi-Pasta-Ulam Chains},
author = {R. Reigada and A. Sarmiento and Katja Lindenberg},
journal= {arXiv preprint arXiv:cond-mat/0205323},
year = {2009}
}