CDUFD Supplementary Material IV: Emergence of Spacetime, Gravity, and Cosmology from Macroscopic Self-Consistency and Lovelock Uniqueness

Version 2.0 (May 2026) represents a fundamental theoretical upgrade from the previous version. The three core changes are: (1) A rigorous methodological distinction between "emergence" (generation of novel macroscopic structures, e.g., the smooth manifold and metric from the discrete network) and "solution-space reduction" (screening of a pre-existing mathematical candidate space by physical constraints). (2) The gravitational dynamics derivation path is restructured around macroscopic self-consistency screening and Lovelock's uniqueness theorem---the Einstein-Hilbert action is the unique survivor after eliminating candidates that lack a stable vacuum. The Verlinde entropic gravity path is removed; Jacobson's thermodynamic derivation is repositioned as a consistency verification tool. (3) A new concept of "gravity as a coupled collective mode" is established: the relaxation of spacetime toward the self-dual point provides the universal reference dynamics that all matter fields follow according to their geometric coupling strength, providing the dynamical origin for the critical lag mechanism in the fermion mass spectrum. Three boundary open problems (axiomatization of z=1, critical scaling of G, and first-principles derivation of the entropy-area coefficient) are honestly marked.