Heat conduction in one dimensional nonintegrable systems
  Two classes of 1D nonintegrable systems represented by the Fermi-Pasta-Ulam (FPU) model and the discrete $\phi^4$ model are studied to seek a generic mechanism of energy transport in microscopic level sustaining macroscopic behaviors. The results enable us to understand why the class represented by the $\phi^4$ model has a normal thermal conductivity and the class represented by the FPU model does not even though the temperature gradient can be established. 
Bambi Hu, Baowen Li, and Hong Zhao (Department of Physics and Centre   for Nonlinear Studies, Hong Kong Baptist University, ...