Past Seminars Seminários Já Decorridos 2015

Enviromentally induced, emergent patterns in active suspensions. From confinement to hydrodynamic speed up.

By: Ignacio Pagonabarraga
From: University of Barcelona
At: Faculdade de Ciências, Ed. C1, 1.3.14
[2015-11-12] 11:15

Active systems generate motion due to energy consumption, usually associated to their internal internal metabolism. As a result, these systems are intrinsically out of equilibrium and their collective properties emerge from a balance  between particle direct interactions and the indirect coupling to the medium in which they displace. In the case of active particles suspended in a liquid, their dynamics  is affected by the liquid in which they swim. Moreover, usually active particles in the microscale (from molecular motors to microorganisms) move in constrained environments. Both the liquid and confinement interfere with the  internal mechanisms that generate  particle propulsion. Therefore, a consistent dynamical approach that accounts for the active particles and the liquid motion on the same footing is required  to analyze particle motion and quantify their self-assembly and ability to generate intermediate and large-scale structures.
I will analyze the impact that the environment has on the effective motion of different type of active particles, and the qualitatively new modes of motion that develop as a result of such  interactions.