Vicsek Flocking Model

Alignment, noise, and the order-disorder transition in self-propelled particles

Controls

Order Parameter

φ = 0.00
Phase: —
Initializing…

Physics

Vicsek model (1995): N particles move with constant speed v. Each updates heading to the mean angle of neighbors within radius r, plus noise η.

Order parameter: φ = |⟨e^{iθ}⟩| ∈ [0,1]

φ≈1 → ordered flock; φ≈0 → disordered gas. Critical noise η_c separates phases — a continuous phase transition.