The Permission Geometry of α≈1/137 Why Enclosure, Dimensionality, and Matter Close in Three Dimensions

This paper presents a conjectural extension of a grammar-layer foundations framework in which the fine-structure constant α ≈ 1/137 is interpreted as a geometric permission threshold. The work explains why stable matter closes only in three dimensions, why light remains non-noun and timeless, and why physical constants must lie within a Goldilocks band that permits enclosure without saturation. The framework advances by negative proof, identifying failure modes outside the viable regime, and proposes falsifiable structural constraints and experimental probes without deriving constants or introducing new dynamics.