Physics

Prof. Surajit Sen
State University of New York,Buffalo, NY

A granular chain held between end walls is a strongly nonlinear (and non-integrable) dynamical system. Any perturbation initiated in this chain travels as a solitary wave. When dissipation is switched off, such a system would eventually end up with equipartitioned energy. This is the first example of a strongly nonlinear dynamical system that equipartitions and hence is a non-trivial extension of the works of Ruffo et al (1985) and Lvov et al (2015) on similar findings in the Fermi-Pasta-Ulam-Tsingou system in the weakly nonlinear regime. In spite of the attainment of equipartitioning, these systems also support unusual physical processes such as the existence of rogue fluctuations (like rogue waves in the seas) and co-existent states such as both solitary waves and phonon-like backgrounds with minimal interactions. The talk shall introduce the granular chain problem and develop the physics involved at a largely intuitive level.

Research partially supported by the US Army Research Office

Collaborators: Michelle Przedborski, Yoichi Takato, Alexandra Westley, Han Ding, Thad Harroun