Speaker
Ken Sekimoto
(University Paris Diderot and ESPCI)
Description
The first part of the talk deals with a method of
coarse-graining based on mechanical viewpoint. We study the
overdamped dynamics, either in equilibrium or
non-equilibrium, of dense medium consisting of mesoscopic
elements. Essentially based only on the
momentum-conservation, we found that the Irving-Kirkwood
type formula are the generic expressions for the macroscopic
momentum and angular momentum fluxes with whatsoever the
mesoscopic structures and dynamics,
In the second part we discuss the well-known Newton's cradle
but with a modified repulsive interaction. This system
realizes the separation of timescales of dynamics and, as a
result, the cluster of particles behaves as a single rigid
body. We show our numerical findings*, experimental
realizations, and the coarse-grained mechanical model.
Analogy is evoked to Mossbauer effects as quantum counterpart.
*PRL 104, 2010. The theoretical works have been done in
collaboration with Dr. Antoine Fruleux, and the experiments
are conducted by three students, Karim Alloubia, Romain
Arteil and Mehdi Benane.
