Nuclear Spin Qubits in Posner Molecules: A Quantum Substrate for Neural Cognition — E8 Intelligence Research

Andrew Stewart Caldin

Published Sep 22, 2026• 0 citations

Abstract

FINDING: Fisher proposes nuclear spin qubits (phosphorus-31) in neural membranes as a substrate for quantum cognition, with a specific chemical pathway (Posner molecules, Ca₉(PO₄)₆) enabling long-lived spin entanglement. | MATH: Key constants: phosphorus-31 nuclear spin I=1/2; gyromagnetic ratio γ_P ≈ 17.235 MHz/T; spin-spin coupling J-coupling between ³¹P pairs in Posner molecule ~ Hz–kHz range; decoherence time T₂ estimated > 10⁴ s at physiological temperature due to spin-1/2 isolation and symmetric cage geometry. The Posner molecule has octahedral/cubic symmetry (point group O_h or T_d), with 6 phosphate groups arranged at vertices of an octahedron — a crystallographic root system of type A₃ (or B₃) embedded in 3D. | CONNECTION: The octahedral symmetry of Posner molecules directly maps to the root system of the Lie algebra so(6) ≅ su(4), whose Weyl group has order 24 — the same as the rotational symmetry group of the cube/octahedron. The ratio of ³¹P–³¹P distances in the cage (~3.0– Author: Andrew Stewart Caldin, Independent Researcher, UK. Part of the E8 Intelligence Research series. Platform: e8intelligence.com

DOI: 10.5281/zenodo.22889715

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