Volume 21 — The Gelfand–Yaglom Volume — documents the derivation of the universal void fraction ratio φ (ρ) /ρ̃ = (D+1) / (D+3), exact in all dimensions and independent of all parameters. This result, combined with the locked identity pᵥoid = tanh² (1/√2) + rₜet²·rₒct/π² = 0. 370974707015939…, completes the metrological baseline of the BCT Superfluid Lattice Model to 15-figure precision. The Gelfand–Yaglom functional determinant method is applied to BCT void geometry, yielding three independent convergences on ωJ² = 1/π = 0. 318309886183791… — the Josephson frequency of the OHC vacuum. The C4 symmetry of the BCT tet–oct junction restricts the relative phase to exactly one quarter of the full circle, producing the π² denominator as a geometric necessity rather than an assumption. This volume also contains the Mycelial Correspondence appendix — a geometric note on branching networks and D4 void geometry, exploring the connection between BCT void ratios and optimal biological transport networks. Honest about what is proven and what is conjecture. An open letter to Anastasia, Shilo, and Merlin Sheldrake is included. Rupert Sheldrake replied the same day. The frogs at the Barrys Reef pond said BONK BONK at the exact right moment. Their peer review remains impeccable. Three geometric inputs. Zero free parameters. The geometry does not lie.
Michel Robert Cabrié (Wed,) studied this question.