STAGE 1 · RANDOM Maximum boundary energy cool STAGE 2 · CLUSTERING domain wall Domains reduce boundary energy cool STAGE 3 · ORDERED Minimum boundary energy BOUNDARY ENERGY high reduced minimal Left-handed Right-handed Domain wall Shear stress Shared flow

Figure 12.2. Spontaneous symmetry breaking as chirality clustering. Stage 1: Above TEW, orbital systems have random chiralities — every mismatched neighbor creates a shear boundary. Stage 2: As the universe cools, same-chirality systems cluster into domains, eliminating internal shear. Domain walls (counter-rotating boundaries between left and right domains) store the remaining boundary energy. Stage 3: One domain wins everywhere. Domain walls are pushed to the edges and dissipate. The substrate settles into its chirally ordered ground state at |φ| = v = 246 GeV.