Quantum Foundations of the Radical-Pair Mechanism


Quantum biology is a new swiftly growing scientific synthesis merging quantum information science with the phenomenological wealth and complexity of biological systems.

Recent theoretical and experimental evidence supports the early intuition of the founding fathers of quantum mechanics that biological systems should be influenced by the intricacies of quantum physics. Currently, quantum biology is explored mainly along three fronts: photosynthesis, magnetoreception and olfaction. Quantum biology is not about the “static”, atomistic aspect of biological structure but about dynamic effects related to quantum coherence and entanglement influencing biological function. Quantum biology is a uniquely interdisciplinary field combining quantum science, physical chemistry, biochemistry and biology.

Quantum Foundations of the Radical-Pair Mechanism

Our contributions

We were one among the few groups that pioneered the field of quantum biology. We introduced the study of the fundamental quantum dynamics of the radical-pair mechanism. Radical-ion-pair reactions are spin-dependent biochemical reactions relevant to photosynthesis and the avian magnetic compass.

The radical-pair mechanism, the cornerstone of the field of spin chemistry, was known since the 1960’s. We unraveled the rich quantum-information science behind this biological mechanism, showing that concepts like quantum measurements, the quantum Zeno effect, measures of quantum coherence and even the quantum-communications concept of quantum retrodiction are necessary to understand the underlying quantum dynamics of radical-pairs.

Most recently, we introduced the tools of quantum metrology to estimate the fundamental magnetic sensitivity of this kind of biochemical magnetometers. 

In a nutshell, we have shown that almost the entire conceptual framework of modern quantum science is required to understand the spin dynamics of a biochemical reaction, thus making a very strong case for the paradigm of quantum biology. We have published several papers on the subject, along with a comprehensive review.