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Updated: May 9, 2026
06:42
Generation and Coherent Control of Pulsed Quantum Frequency Combs
Published on: June 8, 2018
Quantum coherence and entanglement in the avian compass
James A Pauls1, Yiteng Zhang, Gennady P Berman
1Goshen College, Goshen, Indiana 46526, USA.
Summary
Quantum entanglement in radical pairs may enable bird navigation via geomagnetic fields. However, current models lack orientation sensitivity, suggesting birds cannot directly use this for navigation.
Area of Science:
- Quantum Biology
- Bio-magnetism
- Avian Navigation
Background:
- The radical-pair mechanism is a leading theory for avian navigation in Earth's magnetic field.
- The role of quantum entanglement within this mechanism remains under-explored.
- Previous models have not fully elucidated the quantum aspects of this navigation strategy.
Purpose of the Study:
- To investigate the lifetime of radical-pair entanglement under varying magnetic field conditions.
- To assess the potential of radical-pair entanglement for avian navigation.
- To propose and analyze a modified model for enhanced entanglement sensitivity.
Main Methods:
- Theoretical study of radical-pair entanglement lifetime as a function of magnetic field magnitude and direction.
- Analysis of orientation sensitivity of entanglement in geomagnetic fields.
- Development of a novel model replacing hyperfine interactions with local magnetic fields.
Main Results:
- Radical-pair entanglement persists long enough in birds to be potentially utilized for navigation.
- Current radical-pair entanglement shows insufficient orientation sensitivity in the geomagnetic field for direct navigation.
- The proposed model demonstrates longer-lasting entanglement and angular sensitivity in weak magnetic fields.
Conclusions:
- Quantum entanglement in radical pairs is a plausible, yet not fully exploitable, component of avian magnetoreception.
- The proposed model offers a promising avenue for understanding orientation-dependent quantum effects in navigation.
- Further research is needed to refine models and experimentally verify the role of quantum entanglement in bird navigation.
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