Confined Curvature Bounce Theory: Covariant Matching Constraint Formulation

This manuscript introduces Confined Curvature Bounce Theory (CCBT), a speculative covariant effective model for nonsingular black-hole interiors and possible cosmological coupling. The theory proposes that when an invariant curvature threshold is reached, a confined curvature-bounce phase replaces the classical singularity, producing an internal support-scale expansion without requiring white-hole ejection. The model distinguishes the external apparent-horizon radius from the internal proper support length, introduces a hierarchy L₁ ≃ L₂ < L₃ <. . . < Lₙ << L₍+₁, and explores how the resulting active curvature sector could behave as an effective negative-pressure component after cosmological coarse-graining. The paper is presented as a theoretical hypothesis and effective-model framework, not as established physics or as a complete derivation from a confirmed theory of quantum gravity. Version 7: This version updates Confined Curvature Bounce Theory (CCBT) by incorporating covariant matching constraints and the distinction between internal support deconfinement and true covariant apparent-horizon disappearance. The manuscript consolidates the metastable quantum-geometric condensate formulation with later companion tests on dark-energy closure, ADM screening, near-horizon critical matching, projection-rate dynamics, and covariant spherical matching. The dark-energy extension is stated as conditional on front-normalized support growth, ADM screening, and covariant exterior matching.