Causal Memory Gravity II: Unified Cosmology and Galactic Dynamics with a DPN-Saturated SEM-RAR Response

Abstract

Spiral galaxies rotate faster in their outskirts than Newtonian dynamics predicts from their observed baryons, and they do so with striking regularity. Once the baryonic acceleration gb is known, the measured acceleration follows a tight radial acceleration relation across galaxies of very different mass, brightness, and morphology. Causal Memory Gravity (CMG) models spacetime at the Planck scale as a network whose slow modes give gravity a finite memory. This paper organizes the galactic response through two factors: a critical spectral-elastic memory (SEM) contribution √(g†gb) and a finite-channel occupancy factor x/(ex − 1), where x = √(gb/g†). Together they give: gobs = gb / [1 − exp(−√(gb/g†))] This is exactly the exponential radial acceleration relation, and it reproduces the baryonic Tully–Fisher scaling in the low-acceleration limit. The empirical law itself is not new; the paper adds a proposed physical decomposition. The square-root response follows from the stated static critical SEM action and conditional no-slip metric ansatz, while the occupancy factor remains to be tested against explicit DPN channel statistics. The profiled SPARC analysis of 175 galaxies and 3,391 rotation-curve points gives g† = 1.1735 × 10−10 m s−2 and an intrinsic velocity scatter σint = 5.83 km s−1. Because SEM–RAR is algebraically identical to exponential RAR, the difference lies in its proposed SEM/DPN interpretation rather than in a statistically distinct fit. The paper keeps three parameter levels separate: the action parameters ηact and βrate, the DESI-facing fixed-background closure ηcl and βIR, and the galactic scale g†. DESI gives Ag = 0.9962 ± 0.0437, a free-amplitude null test consistent with unity at 0.086σ. No fundamental identification between these parameter levels is imposed. The C4 high-N audit retains the conditional reduced benchmark: g† ≃ [ξ∞/(e − 1)] cβrate, with ξ∞ ≃ 0.297 and βrate/H0 ≃ 1.03 The elastic spectral gap remains construction-dependent. Galaxy lensing, clusters, and nonlinear structure provide separate tests; the CLASH/web pilot produced a gated data pipeline but no estimate of the cluster residual bC. The decisive next step is a common normalized DPN ensemble that returns the cosmological, nonlinear, and galactic response scales from one construction. For the full CMG corpus, theory map, and related materials, visit: cmg.beogradpc.com