ψ-Potential: The Residual Field of Retention — A Structural Energy Component Beyond Dynamical Spacetime

This work introduces the ψ-Potential — a residual, non-dynamical energy component arising from the Λψ term of ψ-Retention Cosmology. Unlike classical energy forms based on flux, curvature, or kinetic terms, the ψ-Potential persists when spacetime collapses, when geometry becomes undefined, and when dynamical evolution ceases to exist. It provides the structural substrate that stabilizes large-scale correlations, produces the late-time growth plateau, explains the Planck Aₗ anomaly, reduces the ISW amplitude, and links multiple cosmological tensions under a single invariant. The ψ-Potential remains finite in post-metric regimes, including black-hole interiors and near-singularity domains, and constitutes the first strictly structural energy component in cosmology — a pre-quark, pre-geometric field of persistence. This article formalizes the definition of ψ-Potential, derives its observational signatures, and establishes its role as the fundamental energy of retention in the ψ-Architecture Research Series (Vol. IV).