Nuclear Spin Qubits in Posner Molecules: A Physical Basis for Quantum Cognition — E8 Intelligence Research

FINDING: Matthew Fisher proposes nuclear spin qubits (phosphorus-31) in Posner molecules as the physical substrate for quantum cognition, with decoherence timescale ~10⁵ s and a specific six-spin cluster geometry. | MATH: Fisher's model requires \( ^{31}\text{P} \) nuclear spin \( I = 1/2 \), gyromagnetic ratio \( \gamma/2\pi \approx 17.235 \, \text{MHz/T} \); Posner molecule \( \text{Ca}_9(\text{PO}_4)_6 \) contains 6 phosphate groups → 6 coupled spins; decoherence time \( T_2 \sim 10^5 \, \text{s} \) at physiological temperature via spin-freezing (Zeno-like effect); quantum error threshold satisfied if \( T_2 / T_{\text{gate}} > 10^4 \). Key symmetry: Posner cluster has \( S_6 \) (or \( C_3 \)) rotational symmetry — a 60° rotation axis, linking to hexagonal/crystallographic order. | CONNECTION: The \( S_6 \) point group (proper 6-fold rotation) is a crystallographic symmetry — directly related to the hexagonal lattice (root system \( A_2 \), base-60 division of circle). The 6-spin cl

Author: Andrew Stewart Caldin, Independent Researcher, UK. Part of the E8 Intelligence Research series. Platform: e8intelligence.com