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Updated: Jun 3, 2026
06:42
Generation and Coherent Control of Pulsed Quantum Frequency Combs
Published on: June 8, 2018
Sustained quantum coherence and entanglement in the avian compass
Erik M Gauger1, Elisabeth Rieper, John J L Morton
1Department of Materials, University of Oxford, Oxford, United Kingdom.
Physical Review Letters
|March 17, 2011
Summary
Life may exploit quantum phenomena like superposition and entanglement, as seen in birds' magnetic sense. These quantum effects persist longer in birds than in artificial systems, challenging the "warm and wet" life paradigm.
Area of Science:
- Quantum Biology
- Bio-magnetism
- Avian Navigation
Background:
- Quantum superposition and entanglement typically decay rapidly in artificial systems without cryogenic temperatures.
- The ability of certain migratory birds to sense Earth's magnetic field suggests a potential biological mechanism for quantum phenomena.
Purpose of the Study:
- To investigate whether life could have evolved to exploit delicate quantum phenomena.
- To analyze the duration of quantum effects in the avian compass using the radical pair model.
Main Methods:
- Application of quantum information theory.
- Analysis of experimental observations of the avian compass.
- Utilizing the established radical pair model.
Main Results:
- Quantum superposition and entanglement are sustained in the avian compass for at least tens of microseconds.
- The observed durations exceed those achieved in the best comparable artificial molecular systems.
Conclusions:
- Living systems, like the avian compass, can sustain quantum phenomena for significant durations.
- This finding challenges the notion that biological systems are too "warm and wet" for enduring quantum effects.
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