Functional Stability as a Cosmological Selection Criterion: A Framework for Universe Viability

We propose a formal framework in which cosmological existence is operationally equivalent to functional persistence: a universe exists if and only if its internal configuration does not collapse under its own rules. This framework, the Theory of Compiled Universes (TCU), generalises Smolin's Cosmological Natural Selection (CNS) by replacing its specific reproductive mechanism and selection criterion with a general functional stability criterion Δ applicable across logically distinct universe configurations. The central formalism introduces three connected structures. First, a unified stability criterion Δ(u,t) = (Λ̃(u,t), ε̃(u,t)) that distinguishes dynamic collapse (Lyapunov divergence) from entropic collapse (thermodynamic saturation), where the asymmetry between the two components is mandated by the second law of thermodynamics. Second, a Hellinger distance metric between the logical configurations of distinct universes, formalising multiversal isolation as a graded rather than binary property. Third, a differential prediction derived exclusively from the graded isolation principle: a CPT-symmetric partner universe with Hellinger distance H* ∈ (0,1) should produce gravitational overlap without electromagnetic interaction — a mechanism for dark matter that neither CNS nor the Boyle–Turok CPT model produces from this formalism. Additional predictions include Majorana neutrino mass (shared with Boyle, Finn & Turok 2018), suppression of primordial gravitational waves, and non-random low-frequency correlations in the CMB power spectrum. The exclusively differential prediction in the computational domain is the statistical clustering of functional universes in configuration space, testable by simulation.