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Irreversible Dynamics of Vortex Reconnections in Quantum Fluids
Alberto Villois1, Davide Proment2, Giorgio Krstulovic3
1Department of Physics, University of Bath, Bath BA2 7AY, United Kingdom and School of Mathematics, University of East Anglia, Norwich Research Park, Norwich NR4 7TJ, United Kingdom.
Physical Review Letters
|October 30, 2020
Summary
Vortex reconnections in quantum fluids show time-irreversible dynamics, separating faster than approaching. This asymmetry is linked to sound pulse generation, offering insights into turbulent energy transfer.
Area of Science:
- Quantum fluid dynamics
- Turbulence theory
- Vortex dynamics
Background:
- Vortex reconnections are fundamental in fluid dynamics.
- Understanding their dynamics is crucial for turbulence.
- Quantum fluids offer a unique system to study these phenomena.
Purpose of the Study:
- To investigate the statistical properties of vortex reconnections in quantum fluids.
- To determine if vortex reconnection dynamics are time-reversible.
- To identify the physical mechanisms driving any observed irreversibility.
Main Methods:
- Statistical analysis of vortex reconnections.
- Numerical simulations using the Gross-Pitaevskii model.
- Evolution of various vortex Hopf link configurations.
Main Results:
- Vortex reconnection dynamics were found to be time-irreversible.
- Reconnecting vortices separate significantly faster than they approach.
- This asymmetry was quantitatively linked to the generation of a sound pulse post-reconnection.
Conclusions:
- The study provides evidence for time-irreversible vortex reconnection in quantum fluids.
- Sound pulse generation is identified as a key factor in this asymmetry.
- Findings may advance understanding of energy transfer in classical and quantum turbulence.
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