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arXiv · 1208.5621

Multicanonical distribution: Statistical equilibrium of multiscale systems

Domingos S. P. Salazar·Giovani L. Vasconcelos
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Abstract

A multicanonical formalism is introduced to describe statistical equilibrium of complex systems exhibiting a hierarchy of time and length scales, where the hierarchical structure is described as a set of nested "internal heat reservoirs" with fluctuating "temperatures." The probability distribution of states at small scales is written as an appropriate averaging of the large-scale distribution (the Boltzmann-Gibbs distribution) over these effective internal degrees of freedom. For a large class of systems the multicanonical distribution is given explicitly in terms of generalized hypergeometric functions. As a concrete example, it is shown that generalized hypergeometric distributions describe remarkably well the statistics of acceleration measurements in Lagrangian turbulence.

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BibTeXRIS

Domingos S. P. Salazar, Giovani L. Vasconcelos. 2012-11-14. Multicanonical distribution: Statistical equilibrium of multiscale systems. https://doi.org/10.1103/physreve.86.050103

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