BU04 Global Physical Admissibility under Single Universe Boundary Consistency

Abstract This paper develops Global Physical Admissibility under Single-Universe Boundary Consistency as a positive consequence theorem within the single-universe boundary framework. Its central claim is that global physical admissibility is not an independent assumption, but a standing derived from global boundary consistency. Let B_U denote the condition that physical boundary conditions remain globally identical, invariant, and non-drifting throughout the total domain U. The paper shows that once B_U holds, three consequences follow in a tightly ordered way: global law-level admissibility L_U, global constant-level admissibility C_U, and single-valued settlement admissibility R_{\text{single}}. The argument is deliberately restrictive. It does not claim that every local formula, approximation, or scale-dependent model automatically becomes globally valid. Instead, it distinguishes foundational admissibility from local effective success. What B_U secures is the standing of globally unified physical law, globally stable constant structure, and non-branching settlement within one ontological universe. This yields a clean criterion for separating universe-level physics from local projection-level theory. The paper therefore reframes admissibility as a structural consequence of a single globally fixed boundary background. Physical intelligibility at the highest level depends on the persistence of one coherent admissibility domain. Global physics is thus derived not from explanatory expansion, but from boundary consistency itself.