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.
Andrew John Paton (Thu,) studied this question.