Independent Convergence: IE-004 and the Universality of Coupling Attractors

Establishes IE-004: independent systems with diverse physical origins converge on alpha=1.920=48/25 through different d-cascade trajectories. Five independent domains analyzed: biological thermoregulation, urban heat island, Passivhaus thermal dynamics, ancient architectural thermal mass, nuclear physics. Independent confirmation: Neilsen et al. (2015) Sgr A* X-ray flare analysis (xi=1.92±0.03). Convergence is a universal attractor not a coincidence. GCT Letters series.