Eur. Phys. J. B 5, 793-800 (1998)
https://doi.org/10.1007/s100510050504

Metastable states in cellular automata for traffic flow^*

¹ Theoretische Physik/FB 10, Gerhard-Mercator-Universität Duisburg, 47048 Duisburg, Germany
² Institut für Theoretische Physik, Universität zu Köln, 50937 Köln, Germany

Corresponding author: ^a as@thp.uni-koeln.de

Received: 26 March 1998
Accepted: 17 April 1998
Published online: 15 October 1998

Abstract

Measurements on real traffic have revealed the existence of metastable states with very high flow. Such states have not been observed in the Nagel-Schreckenberg (NaSch) model which is the basic cellular automaton for the description of traffic. Here we propose a simple generalization of the NaSch model by introducing a velocity-dependent randomization. We investigate a special case which belongs to the so-called slow-to-start rules. It is shown that this model exhibits metastable states, thus sheding some light on the prerequisites for the occurance of hysteresis effects in the flow-density relation.