TY - JOUR PY - 2014// TI - Probabilistic physical characteristics of phase transitions at highway bottlenecks: incommensurability of three-phase and two-phase traffic-flow theories JO - Physical review E: Statistical, nonlinear, and soft matter physics A1 - Kerner, Boris S. A1 - Klenov, Sergey L. A1 - Schreckenberg, Michael SP - 052807 EP - 052807 VL - 89 IS - 5 N2 - Physical features of induced phase transitions in a metastable free flow at an on-ramp bottleneck in three-phase and two-phase cellular automaton (CA) traffic-flow models have been revealed. It turns out that at given flow rates at the bottleneck, to induce a moving jam (F→J transition) in the metastable free flow through the application of a time-limited on-ramp inflow impulse, in both two-phase and three-phase CA models the same critical amplitude of the impulse is required. If a smaller impulse than this critical one is applied, neither F→J transition nor other phase transitions can occur in the two-phase CA model. We have found that in contrast with the two-phase CA model, in the three-phase CA model, if the same smaller impulse is applied, then a phase transition from free flow to synchronized flow (F→S transition) can be induced at the bottleneck. This explains why rather than the F→J transition, in the three-phase theory traffic breakdown at a highway bottleneck is governed by an F→S transition, as observed in real measured traffic data. None of two-phase traffic-flow theories incorporates an F→S transition in a metastable free flow at the bottleneck that is the main feature of the three-phase theory. On the one hand, this shows the incommensurability of three-phase and two-phase traffic-flow theories. On the other hand, this clarifies why none of the two-phase traffic-flow theories can explain the set of fundamental empirical features of traffic breakdown at highway bottlenecks.

Language: en

LA - en SN - 1539-3755 UR - http://dx.doi.org/ ID - ref1 ER -