Thermal Conductivity for a Momentum Conservative Model
نویسندگان
چکیده
Abstract. We introduce a model whose thermal conductivity diverges in dimension 1 and 2, while it remains finite in dimension 3. We consider a system of oscillators perturbed by a stochastic dynamics conserving momentum and energy. We compute thermal conductivity via GreenKubo formula. In the harmonic case we compute the current-current time correlation function, that decay like t in the unpinned case and like t if a on-site harmonic potential is present. This implies a finite conductivity in d ≥ 3 or in pinned cases, and we compute it explicitely. For general anharmonic strictly convex interactions we prove some upper bounds for the conductivity that behave qualitatively as in the harmonic cases.
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