Abstract
Spatially distributed chemically reacting systems under far from equilibrium conditions can give rise to waves of chemical concentration. Such waves play a major role in a variety of phenomena in living systems. Probably the most well‐characterized chemical waves are those found in the Belousov–Zhabotinsky (BZ) reaction. If one or more species in a reaction that gives rise to chemical waves is photosensitive, light can be used to control these reaction–diffusion waves and wave‐driven active gel locomotion. For more details see the Concept article by I. R. Epstein and Q. Gao on page 11181 ff.