A Primer on Computable Wavefunction Realism: A Finite-Information Ontology for Quantum Mechanics

Computable Wavefunction Realism (CWFR) is an ontological framework for quantum theory grounded in the semantic requirements of explanatory realism. Standard continuum ontology violates two stability conditions: domain instability, in which well-posed dynamics can map admissible states to states with non-denoting magnitudes; and range instability, in which predicates defined on topologically thin sets cannot ground stable physical distinctions. CWFR enforces the minimal corrections via four structural postulates: Lorentz-invariant spectral band-limitation; restriction to computable ontic states; admissible successor dynamics closed on the ontic domain; and predicate admissibility requiring open truth sets. The continuum Hilbert-space formalism is retained as semantic scaffolding rather than ontological furniture. Classical worlds emerge from refinement geometry as maximal diachronic threads through stability-predicate certifications, dissolving the preferred basis problem by identifying classical alternatives as history-dependent objects rather than components of an instantaneous state decomposition. Branching irreversibility follows as a logical consequence of witness-based certification, not a dynamical postulate. Probability operates on finite Boolean event algebras at every refinement stage, rendering standard frameworks for recovering the Born rule applicable without measure-theoretic idealization. This primer is self-contained and accessible to graduate students in physics, mathematics, and the philosophy of physics.