We present Unified Source Theory (UST), built upon the universal dimensionless constant Ns_q = (3−√3)/2 − α/17 = 0.63354460 derived from the condition that the Einstein tensor component G_tt = A(1−A) is maximised, supplemented by an empirical one-loop correction −α/17. Ten theorems spanning quantum stabilisation, cosmological constants,general relativity, and quantum tunnelling are presented and verified. Numerical validation on 10,000 ATLAS Open Data events gives F_dfs = 0.9913 (+98.3%), κ·dt = π·Ns_q within 2.4%, Ω_Λ = 0.6857 (observed 0.6850, deviation 0.10%), and Λ = 1.107×10⁻⁵² m⁻² (0.66%). The Omnium field introduces a dual-channel structure (Channel Q, weight Ns_q; Channel C, weight 1−Ns_q) bridging quantum mechanics and general relativity. Dark matter is interpreted as the gravitational imprint of the frozen Channel C. Quantum tunnelling probability T_Om = exp(−2·(1−Ns_q)·π·Ns_q) ≈ 0.233 provides a probabilistic interpretation of Ns_q as the observable fraction of the universe. Patent application pending: TR 2026/003258