The Icosahedral Geometry

NOTICE OF SUPERSESSION — Paper 91 v1.0. This version supersedes v0.5 (January 2026). The structural arguments v0.5 presented — the Borwein-Eisenstein correspondence at the closure threshold of 6 = D! = |U(ℤ[ω])|; the D(D+1) = 2·D! identity at D = 3; the 30° kissing half-angle; the 3√3 − 5 solid-angle gap; the connection to Klein's icosahedral group / A₅ — have been properly developed in current-discipline papers in the 2I Universe Programme: - Paper 12, Unity as Closure Capacity: The Borwein Threshold (10.5281/zenodo.18132551)- Paper 175, The Golden Motor (10.5281/zenodo.19283645)- Paper 198, What Eisenstein Was Tracking (10.5281/zenodo.20069158)- Paper 2, 2I Foundations: The Geometric Origin of Dimensionless Constants (10.5281/zenodo.18085101)- Paper 174, The Icosahedral Spectrum (10.5281/zenodo.19258779) Errata in v0.5: (i) Factual error in §4 — D = 1 also satisfies D(D+1) = 2·D! (1·2 = 2 = 2·1!), so v0.5's claim that D = 3 is "the unique dimension where" the identity holds is false; the correct statement is "the only non-trivial value." (ii) The "Theorem 1 (Borwein–Eisenstein Correspondence)" framing in §3 reads under current discipline as STRUCTURAL CORRESPONDENCE rather than Theorem — three quantities coinciding at 6 is suggestive but not a derivation chain. The kissing-number, 3√3 solid-angle gap, and quintic / A₅ arguments are of genuine programme interest and survive in the successor papers above. v0.5 §11 ("The Wiggle Room") remains undeveloped — a candidate for future work. v0.5 is preserved at version-specific DOI 10.5281/zenodo.18303793 for historical reference.