Belousov–Zhabotinsky Reaction
Belousov–Zhabotinsky is the famous oscillating reaction: a beaker that flips colour periodically instead of settling down. This simulation runs a compact cyclic model of it — three concentrations a, b and c live on every cell, each step every cell is stirred together with its neighbours (diffusion) and then a grows at b’s expense, b at c’s and c at a’s: chemical rock-paper-scissors. Started from pure random noise, the field synchronizes itself into expanding target rings and rotating spiral waves within seconds, the same structures seen in a thin dish of the real reagents. The α, β and γ sliders set the three reaction rates and change the wavelength and character of the waves, clicking or dragging injects excitation where you point, and stir re-randomizes the dish. Colours follow a ferroin-style blue–orange–white banding.
Runs 100% in your browser — simulations are computed locally on your device.
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Notes
- Boris Belousov found the oscillation in the 1950s while modelling the Krebs cycle — and journals rejected his paper as thermodynamically impossible. Anatol Zhabotinsky confirmed and extended the work in the 1960s, long before Belousov was vindicated.
- The real chemistry is bromate oxidising malonic acid, catalysed by cerium or ferroin; the Field–Körös–Noyes ("Oregonator") mechanism of 1972 explained the oscillation through a web of autocatalytic bromide reactions.
- A BZ dish is the canonical excitable medium: the same rotating spiral waves appear in heart muscle, where they underlie certain arrhythmias, and in aggregating slime-mould colonies.
- Runs 100% in your browser — simulations are computed locally on your device.
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