Causal-Boundary Disformal Gravity: Exact Kinetic Freeze-Out and Controlled Strong-Field EFT Boundaries

We propose Causal-Boundary Disformal Gravity (CBDG), an effective field theory in which a scalar field is disformally coupled to pressureless dust, inducing a DBI kinetic structure with reality bound 2D₀X < 1. The exact Noether charge gives a positive freeze-out root R★ > 0 in homogeneous collapse. Ghost freedom, weak and strong energy conditions are proven in every timelike direction. The EFT boundary R_sc is a predictivity surface; the non-perturbative interior is reserved for numerical relativity.Document version: CBDG_v27.