Reference Frames Physical Enforcement of Spatial and Temporal Constraint

This paper defines reference frames strictly as physical systems, not abstract coordinate constructions. Using only established physics, it shows that a reference frame exists only where material structure enforces spatial and temporal constraints through stability, rigidity, energy management, and maintenance. By treating reference frames as stabilized measurement systems, the paper removes observer-dependence and mathematical idealization, grounding frames in mass, structure, and controlled interaction as necessary conditions for measurement comparability across space and time.