From Normal Diffusion to Superdiffusion of Energy in the Evanescent Flip Noise Limit
نویسندگان
چکیده
We consider a harmonic chain perturbed by an energy conserving noise depending on a parameter γ . When γ is of order one, the energy diffuses according to the standard heat equation after a space-time diffusive scaling. On the other hand, when γ = 0, the energy superdiffuses according to a 3/4 fractional heat equation after a subdiffusive space-time scaling. In this paper, we study the existence of a crossover between these two regimes as a function of γ .
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