CAT'S Theory — No Other Way 2: The Triadic Spectral Boundary, Bifurcated Intent, and the Gravitational Constant in a Plenum

This paper completes the gravitational sector of CAT'S Theory by deriving the dimensionless gravitational coupling α_G with zero free parameters. We recast gravity as Aetheric Buoyancy within an Ic (Intent) superfluid on S³, where Newton's constant G emerges as a curvature residue of displaced plenum volume. The integer skeleton α · (17²/5³) · (1/45)²⁶ is corrected by the plenum tension factor (1 − 1/2912), where 2912 = Σ · dΨ · w = 26 · 7 · 16 — the total geometric load of the plenum on closed-loop phase coherence. The result sits at −18.9 ppm from CODATA, within G's own 22 ppm measurement uncertainty. We define the Topological Tension Constant (δτ = π/2912) as the irreducible energy cost of maintaining a closed loop in a pressurized 26-dimensional spectral medium, derived strictly from the spectral budget, the Pattern dimension, and the writhe of the T₃,₈ knot. This ratio redefines inertia not as a property of mass, but as the manifest resistance of the plenum. The result is a total plenum ontology: one constraint, one solution, and no other way. Erratum (September 2026): The original April 2026 edition defined C⋆ ≈ 3.1405 as the ratio of measured α_G to the skeleton. Because the skeleton already carries π through α (Paper 190), this double-counted π. The corrected formula removes C⋆ and applies the plenum tension directly as (1 − 1/2912). The integer derivation of 2912 is unchanged. The numerical result is unchanged.