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Vehicular Traffic: A System of Interacting Particles Driven Far From Equilibrium

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 نشر من قبل Debashish Chowdhury
 تاريخ النشر 1999
  مجال البحث فيزياء
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In recent years statistical physicists have developed {it discrete} particle-hopping models of vehicular traffic, usually formulated in terms of {it cellular automata}, which are similar to the microscopic models of interacting charged particles in the presence of an external electric field. Concepts and techniques of non-equilibrium statistical mechanics are being used to understand the nature of the steady states and fluctuations in these so-called microscopic models. In this brief review we explain, primarily to the nonexperts, these models and the physical implications of the results.



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In the so-called microscopic models of vehicular traffic, attention is paid explicitly to each individual vehicle each of which is represented by a particle; the nature of the interactions among these particles is determined by the way the vehicles i nfluence each others movement. Therefore, vehicular traffic, modeled as a system of interacting particles driven far from equilibrium, offers the possibility to study various fundamental aspects of truly nonequilibrium systems which are of current interest in statistical physics. Analytical as well as numerical techniques of statistical physics are being used to study these models to understand rich variety of physical phenomena exhibited by vehicular traffic. Some of these phenomena, observed in vehicular traffic under different circumstances, include transitions from one dynamical phase to another, criticality and self-organized criticality, metastability and hysteresis, phase-segregation, etc. In this critical review, written from the perspective of statistical physics, we explain the guiding principles behind all the main theoretical approaches. But we present detailed discussions on the results obtained mainly from the so-called particle-hopping models, particularly emphasizing those which have been formulated in recent years using the language of cellular automata.
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