LFIS–01: Derivation of the Cadence Law of Motion

LFIS–01 derives the Cadence Law of Motion (S14), the foundational acceleration relation of the Light Frame Infrastructure Series. The volume shows how the observed acceleration structure follows from Light-Balance Reference / C0-normalization, the finite representational contract, cadence action, Cadence Triangle geometry, frame saturation, frame matching, and curvature projection under slope invariance. The derivation is presented as infrastructure rather than phenomenology: no empirical fitting assumptions are introduced. LFIS–01 establishes the dynamical backbone used by later volumes in the series, while later LFIS volumes provide the full uniqueness proofs, three-mode consolidation, and downstream applications. This version includes refreshed axiom-language alignment, current A2/A3 naming, and final publication-pass cleanup for consistency with the LFIS Notation Guide and the refreshed LFIS 1–38 corpus.