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Breakdown of the Fluctuation-Dissipation Theorem for fast superdiffusion

Ismael V. L. Costa·Rafael Morgado·Marcos V. B. T. Lima·Fernando A. Oliveira
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Abstract

We study anomalous diffusion for one-dimensional systems described by a generalized Langevin equation. We show that superdiffusion can be classified in slow superdiffusion and fast superdiffusion. For fast superdiffusion we prove that the Fluctuation-Dissipation Theorem does not hold. We show as well that the asymptotic behavior of the response function is a stretched exponential for anomalous diffusion and an exponential only for normal diffusion.

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Ismael V. L. Costa, Rafael Morgado, Marcos V. B. T. Lima, Fernando A. Oliveira. 2002-07-30. Breakdown of the Fluctuation-Dissipation Theorem for fast superdiffusion. https://arxiv.org/abs/cond-mat/0207718

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