Vacuum Response Theory: Emergence of Fundamental Interactions, Spacetime Geometry, Quantum Mechanics, and Cosmology from Boundary-Induced Vacuum Reorganisation

We present Vacuum Response Theory (VRT), a unified framework in which spacetime geometry, gravitational dynamics, dark energy, quantum coherence, and nuclear structure emerge from a single physical principle: boundary-induced reorganisation of quantum vacuum energy. VRT distinguishes two vacuum states: the finite ordered quantum vacuum enclosed by a coherence boundary at the Hubble radius, and the surrounding infinite Primordial Dynamic Uncontrolled Vacuum (PDUV). The coherence boundary scale satisfies an exact relation derived from measured cosmological parameters alone. The growth rate β_DE = Ω_m/4 is derived from first principles; κ* = 3.77 is derived from the VRT boundary attractor equation to 0.11%. The covariant VRT action reproduces Einstein's field equations exactly, with γ = β = 1 proved as theorems. The VRT spacetime is geodesically complete with no event horizon. Galaxy rotation curves are reproduced without dark matter; the Hubble tension (ΔH₀ = 5.68 km/s/Mpc) is explained by logarithmic boundary thickness evolution. The Schrödinger and Dirac equations are derived from vacuum mode physics. Ten quantitative falsifiable predictions are presented, including a gravitational wave scalar breathing mode h_b = h_tensor/8, consistent with LVK O3 constraints and testable with LIGO O5. Three parameters remain to be derived from first principles: the inflation boundary speed v_B, the interpolation function ν(y), and the lepton mass ratios.