Rings on strings in excitable media
arXiv:1712.04693 · doi:10.1088/1751-8121/aaa1ba
Abstract
We study the dynamics and interaction of coaxial vortex rings in the FitzHugh-Nagumo excitable medium. We find that threading vortex rings with a vortex string results in significant qualitative differences in their evolution and interaction. In particular, threading prevents the annihilation of rings in a head-on collision, allows generic ring overtaking, and can even reverse the direction of motion of a ring. We identify that an important mechanism for producing this new behaviour is that threaded vortex rings interact indirectly via induced twisting of the threading vortex string.
17 pages, 11 figures. To appear in Journal of Physics A