This paper reconstructs the full kinematic structure of special relativity within the Quantum Lattice Model (QLM) using only the per-radian Planck primitives ħ, ℓₚ, tₚ. Starting from the invariant lattice transport identity c = ℓₚ / tₚ, we show that Lorentz symmetry emerges as a structural consequence of invariant action transport rather than as an independently imposed geometric postulate. The analysis proceeds in three steps. First, action transport per lattice tick and per lattice spacing yields the invariant null bridge E/p = c for massless propagation. Second, proper time is defined operationally as invariant tick accumulation along worldlines, and radar synchronization combined with preservation of the null update bound uniquely determines the Lorentz boost and invariant interval. Third, invariance of the corresponding quadratic form in frequency space, together with the QLM wave relations E = ħω and p = ħk, yields the full relativistic energy–momentum invariant: E² − (pc) ² = (mc²) ². No preferred global lattice slicing is assumed, and no geometric symmetry is imposed a priori. The invariant spacetime interval arises as the macroscopic expression of a microscopic per-tick action-throughput constraint. Special relativity therefore appears as the unique coordinate structure compatible with invariant phase–action transport on the lattice. This work forms Part III of the Quantum Lattice Model series and establishes the special-relativistic sector of the framework from reduced-action primitives alone.
Quinton R. D. Tharp (Tue,) studied this question.