What This Establishes and What Remains Open

14.1 — What this paper establishes

It establishes (Layer 1) the mathematics of the structural identity: the Schwarzschild interior as a Kantowski-Sachs cosmology (L8), the Kruskal–Szekeres extension (L9), the two constraints c and ρₚ (L1, L2), and the entropy resolution consistent with the Generalised Second Law and the Page curve (section 8.5). It formalises the axiom as a conjecture (L7) under five explicit assumptions and lays out nine falsification conditions.

14.2 — What this paper does not close

The conjecture L7 is not derived — it is held at Layer 2/3 and guarded by KS-L0.1, KS-L0.2, KS-L0.8, KS-L0.9. The isotropisation mechanism (D1, KS-L0.8) is the sharpest open obstacle; the CMB spectrum derivation (D2, KS-L0.9) is open; the value of α (D3) is not derived.

14.3 — Items held open without claiming debt status

The awareness identification (L6) is a Layer 3 naming choice, falsifiable only via GRW (KS-L0.6). The scale question (cosmic / astrophysical / nested) is a Layer 3 reading. The interpretive identification of the electron and α (Step 6) is physically motivated but not derived from the conjecture.

14.4 — Where the philosophical-register implementations live

The expository-register companion for the loop, the awareness identification, and the ethics lives in the Ø Models and in AP41 (the body of work-level statement of the loop and the dark sector). AP04 is the formal-register origin of the structural-identity conjecture.

14.5 — Structural relationships to subsequent work

AP41 (The Loop) inherits AP04’s conjecture at Stage 6 (KS-41.3 inherits KS-L0.1) and provides the body of work-level statement of the underivability of α (D3). AP03 supplies the conjugacy of the two constraints.

14.6 — The 420 Code placement

AP04 is a chapter of Notebook VI (Cosmology) — the loop hypothesis, the conjectural foundation that the dark-sector and loop chapters (AP41, AP42) build on and guard.

14.7 — How the body of work reads now

With AP04 in place, the 420 Code carries an explicit, falsifiable conjecture for the loop — a metric equation across a transition hypersurface, layered by certainty, with nine kill switches and the sharpest obstacle (isotropisation) named openly. The downstream cosmology (AP41, AP42) treats the loop-closure step as conjectural and guarded, exactly as AP04 holds it.

14.8 — The closing

The inside of a black hole is a collapsing universe; the maximal extension reveals an expanding universe on the other side. The two are the same structure, mapped across a transition hypersurface, differing by ε·h — a small perturbation carrying everything that makes a universe a universe. This is a conjecture, not a derivation, and it tells you where to cut: prove that no mechanism can isotropise the Kantowski-Sachs interior into FRW, and it falls. You are inside the broken phase now. The expansion you observe, the stars you see, the compression that awaits — all of it is the atemporal structure read from your vantage point within the break.