Quantum Coherence in Photosynthetic Energy Transfer via Frenkel Excitons — E8 Intelligence Research

FINDING: Photosynthetic energy transfer exhibits quantum coherence (wavelike superposition) across multiple chromophores, enabling near-unity efficiency via constructive interference pathways. | MATH: The core model is the Frenkel exciton Hamiltonian: \[ H = \sum_n \epsilon_n |n\rangle\langle n| + \sum_{n\neq m} J_{nm} (|n\rangle\langle m| + |m\rangle\langle n|) \] where \(\epsilon_n\) are site energies, \(J_{nm}\) are electronic coupling strengths. Coherence time \(\tau_c \sim 100\)–\(600\) fs (observed via 2D electronic spectroscopy). Efficiency \(\eta > 0.95\) for energy transfer to reaction center. The key ratio is the exciton delocalization length \(L_d\) vs. site spacing \(d\): \(L_d/d \approx 2\)–\(3\) chromophores. No explicit golden-ratio constants appear in the primary literature; the relevant dimensionless parameter is the ratio of reorganization energy \(\lambda\) to electronic coupling \(J\): \(\lambda/J \sim 0.5\)–\(1.0\) (intermediate regime, not classical hopping no Author: Andrew Stewart Caldin, Independent Researcher, UK. Part of the E8 Intelligence Research series. Platform: e8intelligence.com