Asymmetric Posner Molecule Dynamics Undermine Decoherence-Free Qubit Claims — E8 Intelligence Research

Andrew Stewart Caldin

Published Oct 31, 2026• 0 citations

Abstract

FINDING: Posner molecule Ca₉(PO₄)₆ proposed as biological qubit carrier; recent arXiv work (2108.08822) shows its dynamical ensemble is not symmetric, undermining simple decoherence-free claims. | MATH: Stoichiometry Ca₉(PO₄)₆ → 9 Ca²⁺ + 6 PO₄³⁻; charge balance 9(+2) + 6(−3) = 0. Nuclear spins: ³¹P (I=1/2, 100% abundant) and ⁴³Ca (I=7/2, 0.135% natural abundance) are the candidate qubit registers. Fisher's decoherence estimate: T₂ scaling ~ (γ⁴ n)^{-1} with n = spin density; phosphate cage symmetry nominally O_h (octahedral) in idealized geometry. | CONNECTION: Idealized Posner = octahedral O_h point group → 6 phosphate groups at vertices of octahedron, 9 Ca arranged in a related cage. Octahedral symmetry is a crystallographic root system (B₃/C₃); 6 vertices ↔ 6 roots of A₂⊕A₂ or the 6 faces of a cube. The 9:6 = 3:2 ratio is a perfect fifth — but this is stoichiometric, not a dynamical invariant. The paper's key result: the *dynamical* ensemble breaks the static O_h symmetry, so no pro Author: Andrew Stewart Caldin, Independent Researcher, UK. Part of the E8 Intelligence Research series. Platform: e8intelligence.com

DOI: 10.5281/zenodo.23830703

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