UCM Dark Matter Core Prediction: Test Against the LITTLE THINGS Dwarf Galaxy Survey

The U-Cell Model (UCM) predicts cored dark matter (DM) halo profiles (inner slope α → 0) and a radial acceleration scale g† = f_cold⁴ · c · H₀ = 1.207×10⁻¹⁰ m/s² from the substrate constant f_cold = √(2−π/2) = 0.6551, with zero free parameters. We test these predictions against 26 dwarf irregular galaxies from the LITTLE THINGS survey (Oh et al. 2015; Iorio et al. 2017), using high-resolution VLA HI rotation curves and ³DBAROLO mass models. The mean inner DM slope ⟨α⟩ = −0.32 ± 0.24 is consistent with the UCM cored prediction (α = 0) at 1.3σ, and 2.8σ shallower than the NFW cusp (α = −1). The test is structurally asymmetric: UCM predicts cores from first principles without feedback parameters; NFW predicts cusps equally without free parameters — and lies further from the data. The LITTLE THINGS baryonic Tully–Fisher relation confirms the UCM acceleration scale g† at V_c ∼ 15 km/s, five times below the SPARC median, without deviation. This paper bridges the UCM consistency test from Big Bang Nucleosynthesis (z ∼ 10⁹, Paper 25) to dwarf galaxy rotation curves (r ∼ 1 kpc), spanning fifteen orders of magnitude in spatial scale with a single algebraic constant. Part of the UCM preprint series (ORCID 0009-0005-5088-4339).