SEMINAIRE MERCREDI 28 SEPTEMBRE 2005
14 heures
Salle Séminaire 5
Centre de Physique Théorique
Marseille-Luminy

Philippe Beltrame
Department of Aerodynamics and Fluid Mechanics,
Brandenburg University of Technology, Cottbus (Allemagne)

Title: Heteroclinic cycle dynamics and spherical symmetry: the Geoflow experiment

Abstract: This talk shall focus around heteroclinic orbits dynamics in the
framework of the GEOFLOW-experiment. This spherical Rayleigh-Bénard
experiment on the International Space Station (ISS) aims at
reproducing geo- or astro-physical convective motions. One important
aspect is the utilisation of a central force field, thus the spherical
symmetry is respected. It is already known that structurally stable
heteroclinic cycles between group orbits of equilibria (i.e.
steady-states) can arise due to the symmetry of the problem. We show
that a rich variety of cycles arise near the onset of convection for
the (2,3) and (3,4) mode interactions. The results point out, of
course, the role of the spherical symmetry in the existence of these
complex dynamics but also of other physical symmetries.