Process Dilatation (B-6) Light as Limiting Process Activation

This paper provides a structural account of light within Process Dilatation Theory (PDT). Light is interpreted neither as a particle, wave, nor field excitation, but as the limiting case of relational process activation under finite compatibility constraints. Building on the backbone-level assumption of a maximal admissible activation rate and on previous structural reconstructions of inertia, mass, energy, and gravitation (B-1 to B-5), the present work identifies light as the configuration in which internal binding vanishes and admissible relational transitions remain maximally available. The constant ccc is not introduced as a property of light but as a backbone-level upper bound on admissible activation rates. In the absence of internal binding, no structural degree of freedom remains that could reduce activation below this ceiling. Saturation of ccc therefore appears as a structural consequence rather than a dynamical postulate. Qualitative features traditionally associated with light — absence of rest characterization, limiting propagation speed, and sensitivity to relational inhomogeneities — are reconstructed within a carrier-free process framework. Interference phenomena are interpreted structurally as comparability effects between admissible activation routes. No dynamical equations, field primitives, or spacetime geometry are assumed. Quantitative reconstruction is deferred to subsequent C-level developments.