A central challenge faced by every discrete spacetime framework concerns the emergence of Lorentz symmetry. If physical reality is fundamentally discrete, why does nature appear continuous at observable scales? Why do relativistic phenomena emerge with such extraordinary precision? And why does a universal limiting speed exist? The present work proposes that Lorentz symmetry is not fundamental. Instead, it emerges as a large-scale effective property of discrete H₄ geometry. Building upon previous Parts of the Origin Geometry program, we investigate how statistical isotropy, multiscale screening, and elastic signal propagation collectively generate an effective Lorentzian spacetime description. The framework proposes that the observed velocity scale c corresponds to the maximum propagation speed of geometric disturbances supported by the H₄ substrate. At sufficiently large scales, local anisotropies become progressively screened, yielding an effectively isotropic continuum limit whose governing wave equations exhibit Lorentz invariance. The resulting picture suggests that relativistic spacetime may arise naturally from the collective behavior of an underlying discrete geometric medium. The framework remains intentionally conservative. No derivation of General Relativity is attempted. No quantum gravity model is introduced. Instead, the present Part investigates whether Lorentz symmetry itself may be understood as an emergent geometric phenomenon.
The Duy Tan Truong (Mon,) studied this question.