Quantum Spin-1/2 Phosphorus as Neural Quantum Processing Substrate — E8 Intelligence Research

Andrew Stewart Caldin

Published Oct 7, 2026• 0 citations

Abstract

FINDING: Fisher's quantum cognition hypothesis posits nuclear spin-1/2 phosphorus atoms (³¹P) in phosphate molecules as a substrate for neural quantum processing, with decoherence timescales and spin-coupling geometry as the core mathematical structure. | MATH: Nuclear spin-1/2 (SU(2) symmetry); ³¹P gyromagnetic ratio γ ≈ 17.235 MHz/T; spin-spin coupling J-coupling (scalar, isotropic) and dipolar coupling (tensor, ∝ 1/r³); decoherence time T₂ ~ 10⁻³–10⁻⁰ s for nuclear spins in biological water; quantum error threshold ~10⁻⁴ per gate; Fisher's proposed "Posner molecule" Ca₉(PO₄)₆ — a 9-calcium, 6-phosphate cluster with ³¹P spins arranged in a specific crystallographic geometry (likely octahedral or trigonal prismatic coordination, giving rise to a 6-spin permutation symmetry group S₆). | CONNECTION: The Posner molecule's 6 phosphorus nuclei form a symmetric arrangement — the octahedral point group Oₕ (crystallographic symmetry, order 48) or a related trigonal prism (D₃ₕ). The 6-spin sys Author: Andrew Stewart Caldin, Independent Researcher, UK. Part of the E8 Intelligence Research series. Platform: e8intelligence.com

DOI: 10.5281/zenodo.23203984

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