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Updated: Jun 28, 2026
11:03
An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
Published on: December 4, 2017
Velocity statistics distinguish quantum turbulence from classical turbulence
M S Paoletti1, Michael E Fisher, K R Sreenivasan
1Department of Physics, Department of Geology, and Institute for Research in Electronics and Applied Physics, University of Maryland, College Park, Maryland 20742, USA.
Physical Review Letters
|November 13, 2008
Summary
Quantum turbulence in superfluid helium-4 exhibits non-Gaussian velocity distributions with power-law tails, unlike classical fluid turbulence. Quantized vortex reconnections are identified as the source of these unique statistical features.
Area of Science:
- Quantum fluid dynamics
- Superfluidity
- Turbulence
Background:
- Classical turbulence exhibits near-Gaussian velocity statistics.
- Quantum turbulence in superfluids presents unique phenomena.
- Understanding quantum turbulence is crucial for fundamental physics.
Purpose of the Study:
- To investigate the velocity distributions in decaying quantum turbulence.
- To compare quantum turbulence statistics with classical turbulence.
- To identify the mechanisms driving the observed statistical features.
Main Methods:
- Analysis of solid hydrogen tracer trajectories in superfluid 4He.
- Examination of quantized vortex reconnection events.
- Application of scaling arguments to theoretical models.
Main Results:
- Observed strongly non-Gaussian velocity distributions.
- Identified 1/v(3) power-law tails in velocity distributions.
- Demonstrated that quantized vortex reconnections generate these power-law tails.
Conclusions:
- Quantum turbulence in superfluid 4He has distinct statistical properties compared to classical fluids.
- Quantized vortex reconnections are a key mechanism shaping quantum turbulence.
- The findings advance the understanding of quantum fluid dynamics.
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