Nuclear Spin Qubits in Neural Tissue: A Quantum Cognition Model — E8 Intelligence Research

FINDING: Matthew Fisher proposes nuclear spin qubits (phosphorus-31) in neural tissue as substrate for quantum cognition, with specific molecular and timescale constraints. | MATH: Fisher's model requires: (1) phosphorus-31 nuclear spin-1/2 with gyromagnetic ratio γ ≈ 17.235 MHz/T; (2) coherence time τ_c > 10⁻⁴ s (his "quantum coherence window"); (3) entanglement via dipolar coupling J between ³¹P spins in Posner molecules Ca₉(PO₄)₆ — the key symmetry is the octahedral/cubic arrangement of 6 phosphate groups; (4) spin decoherence rate Γ ∝ (Δω)²·τ_c⁻¹ where Δω is chemical shift dispersion; (5) quantum error correction threshold ~10⁻⁴ per operation. | CONNECTION: Posner molecule Ca₉(PO₄)₆ has crystallographic point group T_h (octahedral symmetry, order 24) — this is the same symmetry class as the root system of the F₄ Lie algebra (24 roots) and the 24-cell in 4D. The 6 phosphate groups form an octahedron (dual to cube), whose vertices correspond to ±e_i axes — a structure with exact 90° Author: Andrew Stewart Caldin, Independent Researcher, UK. Part of the E8 Intelligence Research series. Platform: e8intelligence.com