We introduce analog integrated circuits that imitate a typical model of a reaction diffusion system, called the Belousov-Zhabotinsky (BZ) reaction. The BZ reaction gives us many insights into developing new architectures based on a new computing paradigm such as in active wave computing. The analog unit circuit exhibits both excitatory and oscillatory behaviors with very stiff responses, as obs...

The mechanistic origins of complex responses in chemical systems are traced to the role of chemical or thermal feedback arising from autocatalysis or self-heating. These simple building blocks, which occur widely in chemistry and biochemistry, support behavior ranging from simple clock reactions to sustained oscillations, chaos and spatial pattern formation. Examples discussed include the Belou...

Experiments on the Belousov-Zhabotinsky reaction in a well-stirred flow reactor elucidate one of the routes to chaos, subharmonic intermittency (type III interminency). Measurements conducted as a function of two independent control parameters demonstrate how difficult it is in practice to distinguish this route to chaos from subcritical period doubling transitions with similar chaotic time sig...

Domains containing spiral waves form on a stationary background in a photosensitive Belousov-Zhabotinsky reaction with light-induced alternating nonlocal feedback. Complex behavior of colliding and splitting wave fragments is found with feedback radii comparable to the spiral wavelength. A linear stability analysis of the uniform stationary states in an Oregonator model reveals a spatial symmet...

A pacemaker, regularly emitting chemical waves, is created out of noise when an excitable photosensitive Belousov-Zhabotinsky medium, strictly unable to autonomously initiate autowaves, is forced with a spatiotemporal patterned random illumination. These experimental observations are also reproduced numerically by using a set of reaction-diffusion equations for an activator-inhibitor model, and...

We demonstrate the existence of steadily translating filaments in the Belousov-Zhabotinsky reaction. The filaments have self-reinforcing shapes tracing planar hairpins and constant velocities that are inversely proportional to their width. These features are well described by an analytical solution of the mean curvature flow problem. Using numerical simulations based on an excitable reaction-di...

Spatiotemporal networks are studied in a photosensitive Belousov-Zhabotinsky medium that allows both local and nonlocal transmission of excitation. Local transmission occurs via propagating excitation waves, while nonlocal transmission takes place by nondiffusive jumps to destination sites linked to excited sites in the medium. Static, dynamic, and domain link networks are experimentally and co...

Experimental and computational studies of the formation and evolution of scroll waves in three-dimensional excitable media are presented. Scroll waves are initiated in the photosensitive Belousov-Zhabotinsky reaction by perturbing traveling waves transverse to their direction of propagation. Scroll rings are generated by perturbing circular waves, which expand or contract depending on the stren...