Reaction–diffusion scale selection simulation

Does a structureless chemical soup spontaneously organise into a pattern with a reproducible length scale — set by the chemistry, not by the random seed?

▶ Run the simulationSee the measured result

Units: dimensionless Gray–Scott length units (k_max = 0.5258853 rad/unit; F=0.0866, k=0.0605, Du=0.16, Dv=0.08)

How the lab tests it

Run the Gray–Scott two-species reaction–diffusion system on a toroidal grid from a noisy uniform soup; once it settles, measure the characteristic wavelength λ from the first off-zero peak of the spatial autocorrelation of the activator field, and re-seed to see whether λ recurs while the pattern never does.

What it looks for

a reproducible, seed-independent characteristic wavelength λ (same physics → same scale) — an emergent length with no clean closed-form value (this is the self-replicating/pulse regime, not a linear Turing bifurcation with an analytic wavelength)