Einstein relation in systems with anomalous diffusion

G. Gradenigo a,ba, D. Villamaina c, A. Vulpiani a

Acta Physica Polonica B 44 (2013) 899-912

We discuss the role of non-equilibrium conditions in the context of anomalous dynamics. We study in detail the response properties in different models, featuring subdiffusion and superdiffusion: in such models, the presence of currents induces a violation of the Einstein relation. We show how in some of them it is possible to find the correlation function proportional to the linear response, in other words, we have a generalized fluctuation-response relation.

  • a. CNR-ISC and Dipartimento di Fisica, Università Sapienza
    p.le A. Moro 2, 00185, Roma, Italy
  • b. Institut Physique Théorique (IPhT), CEA Saclay and CNRS URA 2306
    91191 Gif Sur Yvette, France
  • c. Laboratoire de Physique Théorique et Modèles Statistiques (LPTMS),
    CNRS : UMR8626 – Université Paris XI - Paris Sud