Nuclear Spin Qubits in Posner Molecules: Quantum Cognition via Calcium Phosphate — E8 Intelligence Research

Andrew Stewart Caldin

Published Sep 2, 2026• 0 citations

Abstract

FINDING: Matthew Fisher proposes nuclear spin qubits (phosphorus-31) in neural membranes as a quantum processing substrate, with a specific molecular mechanism (Posner molecules, Ca₃(PO₄)₆) enabling long-lived quantum coherence. | MATH: Nuclear spin-1/2 for ³¹P; Posner molecule Ca₉(PO₄)₆ — 6 phosphate groups, 9 Ca²⁺ ions; quantum entanglement lifetime τ ~ 10⁵ s (hours) at physiological temperature; decoherence rate Γ ∝ exp(−ΔE/k_BT) suppressed by spin-singlet pairing; Fisher's key ratio: entanglement fidelity F > 0.99 for ³¹P spin pairs in Posner clusters. | CONNECTION: Posner molecule has **octahedral symmetry (O_h)** — 6 phosphate tetrahedra arranged at vertices of a regular octahedron, a crystallographic point group (order 48). The ³¹P nuclei sit at positions corresponding to the **octahedral root system D₃** (6 vertices ±e₁, ±e₂, ±e₃). The Ca²⁺ ions form a **cuboctahedral shell** (12 vertices, Archimedean solid) — related to the **fcc lattice** and the **root system of F₄**. The ra Author: Andrew Stewart Caldin, Independent Researcher, UK. Part of the E8 Intelligence Research series. Platform: e8intelligence.com

DOI: 10.5281/zenodo.22244985

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