Epidemic Spread on a Random Network (2D)

The 3D original generates and compares three landmark network models as static structures — Erdős–Rényi random, Barabási–Albert scale-free, Watts–Strogatz small-world. This 2D companion fixes the model to Erdős–Rényi and asks what happens on the network rather than how it is built: a discrete-time SIR epidemic spreads node to node along real edges, so the same giant-component threshold that decides whether the graph is even connected also decides whether an outbreak can reach more than a handful of nodes. Drag any node to rearrange the same force-directed layout the 3D page uses, tune infection probability and recovery time, and watch the susceptible/infected/recovered counts trace out on a live chart.