ψ-Shadow Equation: The Retentive Trace Beyond Temporal Extinction

This micro-article introduces the ψ-Shadow Equation, a minimal formal construct describing the persistence of structural difference (Δψ) when classical time approaches extinction. The retentive shadow Sψ is defined as the deviation from the equilibrium floor Δψ₀, stabilized by the Ξ-node and emerging naturally from the ψ-Lagrangian. The work presents Sψ as a topological remainder independent of metric geometry and capable of surviving temporal collapse. This formulation expands the ψ⁸ architecture by establishing retentive shadows as fundamental invariants of structural continuity.