The Dark Sector as a Classification Error

The Dark Sector as a Classification Error A Boundary Analysis of Dark Matter and Dark Energy This paper develops a structural analysis of ontological extraction in contemporary cosmology. Rather than proposing a new cosmological model or disputing the empirical success of Λ\LambdaΛCDM, the manuscript examines whether presently inferred dark-sector structure admits invariant primitive ontological extraction under representational redistribution preserving observational witness constraints. The central result is that dark-sector inference is structurally underdetermined across admissible representational schemes. In particular, explanatory load may be redistributed between: source-side augmentation (e.g., additional gravitating sectors), law-side modification, or alternative representational stabilization structures, while preserving the relevant observational witness class motivating the inference. The manuscript introduces a formalized extraction criterion based on invariance under observationally preserving representational transformation. Under this criterion, presently inferred dark-sector structure fails unique primitive ontological stabilization within the surrogate classes analyzed. A weak-field/Newtonian toy model is developed explicitly demonstrating: witness preservation, redistribution of explanatory load, and failure of invariant primitive extraction across distinct representational constructions. The paper carefully distinguishes: primitive ontology, effective/operational utility, and predictive adequacy. The argument does not deny: the empirical success of modern cosmology, the utility of effective dark-sector modeling, or the possibility of future physical discoveries. Instead, it establishes a boundary condition on when ontological extraction from surrogate-dependent cosmological structure is admissible. The manuscript is positioned as a foundations-oriented contribution at the intersection of: cosmological inference, structural realism, representational equivalence, and ontology in physics. This paper is downstream of: Minimal Conditions for Admissible Construction  The Structure of Admissibility