LFIS–10: Measurement Theory and the Optical Present

LFIS–10 establishes the measurement theory of Light Frame Cadence Geometry: how observers define time, distance, simultaneity, curvature, and measurement validity within finite representability bounds. The volume models an observer as a Light Frame constrained by the contract sphere, with clocks, rulers, signal paths, and observable domains all governed by cadence capacity and TS/TD accessibility. The volume derives cadence-clock behaviour from locally available cadence capacity, defines operational distance through symmetric TS-directed non-torsional return paths, and introduces the Optical Present as an observer-relative simultaneity structure based on phase-matched TS propagation. It also collects the signal-reconstruction rules by which observers infer geometry from time-of-flight, ray bending, redshift, and blueshift, using the photon-transport laws developed in LFIS–09. LFIS–10 completes the first observational infrastructure block of the Light Frame Infrastructure Series by connecting the geometric and electrodynamic volumes to operational measurement, representability-limited observability, and horizon-bounded signal access.