Boundary-Induced Vacuum Effects as Geometric Constraints

This paper establishes a physical necessity constraint on boundary-induced vacuum effects such as the Casimir effect. It demonstrates that once a boundary geometry is fixed, the dimensional form and separation scaling of the resulting vacuum response are determined solely by geometry. Material properties may modify the magnitude of the effect but cannot alter its geometric scaling without violating locality and dimensional consistency. By stripping away model-dependent calculations and interpretation, the paper functions as a no-go filter: any physically consistent description of boundary-modified vacuum energy must decompose into a geometry-fixed structure with only dimensionless material corrections.