Ising Model Sim

2D Ising model — watch the ferromagnetic phase transition at T_c ≈ 2.269

T = 2.27 J/k_B | M | = 0.00 E/N = 0.00

Temperature T: 2.27 Speed:

Magnetization history (|M|, red) and Energy/N (blue)

The 2D Ising model (Lenz 1920, Ising 1925, Onsager exact solution 1944) models ferromagnetism. Spins align at low T (ordered); disorder wins at high T. Critical temperature T_c = 2J/k_B ln(1+√2) ≈ 2.269 — a second-order phase transition.