Short Note / Cover Description:This manuscript presents the definitive formulation of the Z.I.P.P.E.D. Theory, a mechanical framework for spacetime tension that explains flat galactic rotation curves without invoking Dark Matter. Using the Delta Offset (Δ = 0.0004217358) and the Zwanenburg Constant (Z_c = 1.2 × 10^-10 m/s²), the theory reproduces observed galactic velocities across multiple spiral galaxies. The Milky Way Celsus Phenomenon is analyzed in detail, providing both empirical validation and predictive models for outer stellar disks. Extended Abstract / Desknotes:The Z.I.P.P.E.D. (Zipped/Unzipped Physical Elastic Dynamics) Theory offers a unifying framework for galactic dynamics by modeling spacetime as a mechanical tension system. In this approach: Delta Offset (Δ = 0.0004217358) represents the residual tension in spacetime, acting as both a physical and informational constant. Zwanenburg Constant (Z_c = 1.2 × 10^-10 m/s²) provides a linear acceleration term sufficient to explain the flatness of outer galactic rotation curves. The manuscript demonstrates that: Classical Newtonian and Einsteinian mechanics correctly describe inner stellar dynamics (within ~20–50 parsecs). Beyond the transition radius rtr_trt, Z.I.P.P.E.D.-dominated mechanics predict velocities consistent with observations, forming the characteristic "opstanding edge" of rotation curves. Empirical validation is performed against SPARC data and additional galaxies (NGC 3198, NGC 2403, UGC 128), showing residuals below 1 km/s. Predictive models provide testable velocity profiles for outer stellar disks and define the domain of applicability of the theory. This work closes the conceptual loop from microphysics (topological knots and vibrational energy) to galactic and cosmological scales, establishing a reproducible, falsifiable, and unified theory of rotational dynamics. It serves as a foundation for further exploration and peer validation of galactic behavior without Dark Matter assumptions. Keywords / Hashtags:#ZIPPEDTheory #DeltaOffset #ZwanenburgConstant #MilkyWayCelsus #GalacticDynamics #FlatRotationCurves #DarkMatterAlternative #Astrophysics #SPARCValidation #CosmicUnraveling #PredictiveGalacticModel #TopologicalSpacetime