Correlation functions of non-Markovian systems out of equilibrium: analytical expressions beyond single-exponential memory

  title={Correlation functions of non-Markovian systems out of equilibrium: analytical expressions beyond single-exponential memory},
  author={Timo J. Doerries and Sarah A. M. Loos and Sabine H. L. Klapp},
  journal={Journal of Statistical Mechanics: Theory and Experiment},
This paper is concerned with correlation functions of stochastic systems with memory, a prominent example being a molecule or colloid moving through a complex (e.g. viscoelastic) fluid environment. Analytical investigations of such systems based on non-Markovian stochastic equations are notoriously difficult. A common approximation is that of a single-exponential memory, corresponding to the introduction of one auxiliary variable coupled to the Markovian dynamics of the main variable. As a… 
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