This repository contains the computational framework, simulation code, and raw data used in the manuscript "Quantum Entanglement and Information Theory in Radical Pair Navigation." We built the simulation framework using Python and the Quantum Toolbox in Python (QuTiP v4.7). The code models the open quantum system dynamics of the FAD•−/Trp•+ radical pair mechanism (RPM) implicated in avian magnetoreception. The repository includes scripts to compute the following: Spin Hamiltonian Dynamics: Construction of the two-electron spin Hamiltonian, incorporating Zeeman interactions and the dominant hyperfine couplings for both the FAD•− and Trp•+ radicals. Open System Evolution: Integration of the Lindblad master equation to track the time evolution of the singlet and triplet state populations under biological decoherence channels (spin relaxation, environmental dephasing, and radical recombination). Quantum Fisher Information (QFI): Calculation of the symmetric logarithmic derivative and QFI to determine the fundamental angular sensitivity limits of the radical pair compass. Information Theory: Computation of the Shannon mutual information and channel capacity between the Earth's magnetic field orientation and the molecular signaling states.
Chandan et al. (Wed,) studied this question.