Reciprocal Constraint Closure and the Emergent Planck Boundary

This paper formalises a minimal structural mechanism by which lower-bound refinement scales emerge from reciprocal constraint interactions. When localisation cost scales inversely with resolution and induced backreaction scales proportionally with cost, a fixed-point admissibility boundary arises under the stated scaling assumptions. The Planck length appears as a special case under standard quantum and gravitational scaling relations. The formulation does not assume spacetime discreteness and introduces no modified dynamics. Instead, it identifies a structural admissibility limit generated by reciprocal scaling closure, providing a domain-neutral interpretation of minimal scale emergence as a boundary of permissible refinement. An optional final section provides interpretive placement of the closure mechanism within the Paton System’s admissibility framework without altering the derivation.