φ < 0 (trough) φ ≈ 0 φ > 0 (crest) localized quantum

Scalar Field on a Lattice (2D)

This 2D companion drives the exact same finite-difference Klein-Gordon field equation as the 3D version, but renders φ as a flat colour heatmap instead of a tilted 3D surface — a clean top-down read of wave propagation and, as the mass term rises, the field's tendency to clump into short-lived, particle-like lumps.