On the derivation of Fourier’s law for coupled anharmonic oscillators
نویسندگان
چکیده
We study the Hamiltonian system made of weakly coupled anharmonic oscillators arranged on a three dimensional lattice Z2N × Z2, and subjected to a stochastic forcing mimicking heat baths of temperatures T1 and T2 on the hyperplanes at 0 and N . We introduce a truncation of the Hopf equations describing the stationary state of the system which leads to a nonlinear equation for the two-point stationary correlation functions. We prove that these equations have a unique solution which, for N large, is approximately a local equlibrium state satisfying Fourier law that relates the heat current to a local temperature gradient. The temperature exhibits a nonlinear profile.
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