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Violation 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 normal superdiffusion and fast superdiffusion. For fast superdiffusion, we prove that the Fluctuation-Dissipation Theorem does not hold, which induces an effective temperature in the system. This effective temperature is a signature of metastability found in many complex system such as Spin-Glass and granular material.

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Ismael V. L. Costa, Rafael Morgado, Marcos V. B. T. Lima, Fernando A. Oliveira. 2003-04-11. Violation of the fluctuation-dissipation theorem for fast superdiffusion. https://doi.org/10.1209/epl%2Fi2003-00514-3

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