Boundary Entanglement-Entropy Origin of Gravitational Dynamics, Quadratic-Curvature High-Energy Limit, and Three-Step Condensation Gravitational-Wave Spectrum in AQM

Paper XVII gave a closed chain for the recovery of Lorentzian causal structure, ADM type spacetime readout, the Einstein-Hilbert main term, and the Einstein-equation form limit in the low-energy boundary regime. The present paper addresses a different but immediately subsequent question: what is the dynamical origin of the gravitational action, why do quadratic curvature corrections naturally appear at high energy, and how should the massive spin-2 ghost candidate of quadratic-curvature gravity