title: Multicanonical distribution: statistical equilibrium of multiscale systems.
abstract: A multicanonical formalism is introduced to describe the 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.
authors.affiliation: Unidade de Educação a Distância e Tecnologia, Universidade Federal Rural de Pernambuco, 52171-900 Recife, Pernambuco, Brazil.
authors.forename: Domingos S P
authors.initials: DS
authors.lastname: Salazar
authors.forename: Giovani L
authors.initials: GL
authors.lastname: Vasconcelos
mesh_terms: D000054:Acceleration; D000465:Algorithms; D003198:Computer Simulation; D015233:Models, Statistical