Collective effects in transport systems : From molecular motors to pedestrians

Cécile Appert-Rolland (Laboratoire de Physique Théorique, Université Paris-Sud) — April 20

Abstract :
Transport systems often rely on self-propelled agents. At our scale, these agents can be pedestrians or vehicles. But we also find self-propelled molecules inside our cells, the so-called molecular motors, which are responsible for the transport inside the cell. Here, we will focus on several collective effects that occur in these systems.
Inside cells, the transport of cargo often relies on several motors that pull at the same time, and possibly in opposite directions. While this may seem quite inefficient, we will propose several explanations why it may beneficial in the context of intracellular transport.
At the scale of pedestrians, the crossing of flows may lead to the spontaneous formation of structures that we are not necessarily aware of. In particular, we will address the formation of diagonals at the crossing of perpendicular flows.
As a last example, we will present a kinetic model for vehicles driving on a bidirectional road and discuss how the symmetry between the two lanes can be broken above a certain density.

Biography :
Cécile Appert-Rolland is a senior CNRS researcher in the Laboratoire de Physique Théorique at Paris-Sud University in Orsay.
Cécile is an expert in the theory of non-equilibrium transport phenomena. Since the 2000s, she started to investigate non-equilibrium transport in the context of road or pedestrian traffic, as well as intra-cellular transport.

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