Retentive Architecture Beyond Dynamics: A Formal Framework for Structural Persistence in Post-Entropic Regimes

This work introduces a formal framework for retentive architecture, describing how structured difference can persist autonomously after the withdrawal of active dynamics. The paper defines retention as an architectural regime distinct from equilibrium, memory, or control, grounded in the principle of retentive genesis (ψ⁸), a minimal retentive Lagrangian (Λψ), and explicit threshold conditions governing stability. Retentive nodes (Ξ) are shown to arise when structured difference (Δψ) exceeds minimal signal, asymmetry, and scale thresholds, after which they exhibit post-dynamical stability, non-invasive observability, and domain-independent invariance. The framework provides a minimal, falsifiable, and substrate-independent model applicable across physical, informational, and cultural systems, offering a unified language for post-entropic structural persistence.