title: Hidden geometry of traffic jamming.
abstract: We introduce an approach based on algebraic topological methods that allow an accurate characterization of jamming in dynamical systems with queues. As a prototype system, we analyze the traffic of information packets with navigation and queuing at nodes on a network substrate in distinct dynamical regimes. A temporal sequence of traffic density fluctuations is mapped onto a mathematical graph in which each vertex denotes one dynamical state of the system. The coupling complexity between these states is revealed by classifying agglomerates of high-dimensional cliques that are intermingled at different topological levels and quantified by a set of geometrical and entropy measures. The free-flow, jamming, and congested traffic regimes result in graphs of different structure, while the largest geometrical complexity and minimum entropy mark the edge of the jamming region.
authors.affiliation: Department for Theoretical Physics, Jožef Stefan Institute, 1000 Ljubljana, Slovenia.|Vinča Institute of Nuclear Sciences, University of Belgrade, 11351 Belgrade, Serbia.
authors.forename: Miroslav
authors.initials: M
authors.lastname: Andjelković
authors.affiliation: Department of Physics, Indian Institute of Technology Madras, Chennai 600036, India.
authors.forename: Neelima
authors.initials: N
authors.lastname: Gupte
authors.affiliation: Department for Theoretical Physics, Jožef Stefan Institute, 1000 Ljubljana, Slovenia.
authors.forename: Bosiljka
authors.initials: B
authors.lastname: Tadić