This work introduces the ψ-Retentional Cone, a geometric structure unifying three previously independent late-time cosmological signatures: the 1.1–1.6 Δψ-floor soft-step, the retentional growth constant γ ≈ 0.64, and the bifurcation redshift z† ≈ 1.72. Within the ψ-Retention framework, these quantities are shown to form a single conic architecture in the (α, z) parameter space, marking the transition from a dynamical universe to a structurally retentional one. The article formulates and operationally proves the ψ-Retentional Cone Theorem, demonstrating that any cosmology exhibiting (i) a stable Δψ-floor, (ii) a scale-invariant k-plateau, and (iii) a sharp structural bifurcation at z†, necessarily admits a unique retentional cone with axis aligned to γ* and apex anchored at z†. This provides a coordinate-independent geometric interpretation of the universe’s shift from dissipation to retention. Applications include late-time structure formation, Ξ-node memory effects, lensing-residual phenomena, and retentive geometries in conceptual and computational models. The ψ-Retentional Cone establishes a unified structural object governing late-time persistence, offering a new theoretical framework for interpreting cosmological anomalies beyond ΛCDM.
Logacheva Yulia (Tue,) studied this question.