Nonlinear Physics seminar: "From robots uprising to rise of the dead — lessons in engineering and biology from a new type of active particles"

Date: 
Wed, 11/01/202312:00-13:30
Location: 
Danciger B Building, Seminar room
Lecturer:  Matan Yah Ben Zion
Abstract:



Cooperation is vital for the survival of a swarm. No single bird is faster than a jet plane, and no single fish is faster than a speed boat — humans beat individual animals in air, land, and sea. But, when animals cooperate and swarm, they beat us since biblical times. Inspired by non-equilibrium statistical physics I will shed light on cooperative behavior found in the animal kingdom. I will present our recent experimental findings of a new kind of self-propelled particle that is characterized by a charge-like parameter that generalizes the dynamics of known active particles. I will show that this parameter is empirically well-defined, has units of curvature, and stems from a mechanical description of a vibrating walker. I will show that when such a particle has a negative “active charge”, it is attracted to repulsive potentials, effectively going uphill. At the individual level, some animals are known to go uphill, and the proposed force-alignment response suggests a bio-mechanical contribution to this peculiar behavioral trait. Moreover, the force-alignment response leads to unique collective behavior. An ensemble of such active particles spontaneously coordinates the transport of much larger objects, alleviating the dependence on complex circuitry, sensors, or communication. We call such active particles “transportons”, and using both experiments and simulations, I will show that the transport propensity of a swarm of transporters is super-linear with group size, a hallmark of cooperation.