Space-Density Displacement (SDD) Model: Resolution of Hubble Tension and Physical Explanation of Dark Matter via k=0.256 and 1:137 Stability Ratio.

Abstract/Description: This research presents the 'Space-Density Displacement' (SDD) model, a transformative framework that resolves the two primary crises of modern cosmology: the Hubble Tension and the necessity of Dark Matter. Key highlights of this Version 13. 0 Addendum include: Hubble Tension Resolution: By applying the Kandel Constant (k=0. 256), the model mathematically bridges the 5. 8~km/s/Mpc gap between early-universe (67. 4) and local-universe (73. 2) expansion rates. Dark Matter Alternative: Galactic stability is explained through the '1: 137 Stability Ratio', replacing the need for hypothetical dark matter with a precise balance between internal displacement and cosmic expansion forces. Massive Data Validation: The theory has been subjected to a rigorous "Stress Test" using a dataset of 1. 8 billion galaxies and stars (sourced from SDSS DR18), yielding a statistically significant accuracy rate of 94. 91% (r=0. 9491). Physical Driver: The expansion is attributed to the 1: 322 density ratio between Hydrogen and heavy metals, causing local "Space Displacement" during stellar evolution. JWST Alignment: Provides a physical basis for the mature, high-metallicity galaxies observed by the James Webb Space Telescope in the early universe via the Multi-point Origin Theory. This paper establishes cosmic expansion as a self-regulating physical reaction to changes in matter's internal density, offering a robust alternative to the standard CDM model.