Seminar by Takayuki Hiraoka

Collective motion and pursuit-escape behavior in self-propelled particles

Takayuki Hiraoka, Meiji University, Japan.

Collective motion in biological objects such as birds, fish, and
insects has been the subject of mathematical modeling and simulation
studies since 1980s. The Vicsek model[1], despite its simplicity, show
some interesting properties such as a discontinous transition from
order to disorder and giant density fluctuations[2,3]. On the other
hand, the interactions are complex and diverse in actual biological
systems, and little is known about how the different interactions
influence the nature of collective motion. Here we describe the
behavior of purely repulsive self-propelled particle (SPP) model by
numerical simulations. The result indicates the universality of the
order-disorder transition in SPP systems[4]. I will also discuss an
ongoing project on its possible application to predator-prey dynamics.

[1] T. Vicsek et al., Phys. Rev. Lett. 75, 1226 (1995)
[2] J. Toner and Y. Tu, Phys. Rev. E 58, 4828 (1998)
[3] G. Gregoire and H. Chate, Phys. Rev. Lett. 92, 025702 (2004)
[4] T. Hiraoka, T. Shimada, and N. Ito, Phys. Rev. E 94, 62612 (2016)