The Universal Coherence Ratio: From Qubits to Cosmos to Cortex — Why Coherence, Not Speed, Is the True Quantum Resource (Paper XIV-E)

The quantum computing narrative has been dominated by speed. This paper argues that the fundamental quantum resource is not computational acceleration but coherence maintenance. We demonstrate that the RCD framework reveals a characteristic coherence ratio α ≡ Γ/J appearing across radically different physical domains: superconducting qubits (~10⁻⁴), cosmological dark energy (~10⁻⁴), and neural systems (~0.1, critical regime). The universality refers to the structural form α = Γ/J and the necessity of N-signatures, not to a single numerical value. Key thesis: "RCD does not exploit quantum computers to compute more, but to remain coherent longer in regimes where classical control fails." This paper closes the XIV series by unifying mathematical foundations (XIV-A), cosmological application (XIV-B), impossibility theorem (XIV-C), and first-principles derivation (XIV-D) into a cross-domain framework with unified falsifiability criteria. Part of the XIV Series:- XIV-A: Structure (DOI: 10.5281/zenodo.18207097)- XIV-B: Cosmology (DOI: 10.5281/zenodo.18207197)- XIV-C: Necessity (DOI: 10.5281/zenodo.18207252)- XIV-D: First Principles (DOI: 10.5281/zenodo.18213618)- XIV-E: Unification (this paper)