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Published on: March 5, 2014
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Splashes in isotropic media.
1Department of Physics, University of Virginia, P.O. Box 400714, Charlottesville, Virginia 22904-4714, USA.
Physical Review. E
|March 18, 2023
Summary
Splashes in media arise from interfering excitations, with outcomes depending on wave velocities. Negative group velocities can cause converging wave fronts, observed in systems like superfluid helium.
Area of Science:
- Condensed Matter Physics
- Fluid Dynamics
- Wave Phenomena
Background:
- Linear response theory describes medium responses to perturbations.
- Splashes are complex wave phenomena resulting from localized disturbances.
- Understanding splash dynamics is crucial for various physical systems.
Purpose of the Study:
- To explain the physics of splashes in weakly absorbing isotropic media using linear response theory.
- To elucidate the role of phase and group velocities in splash formation and evolution.
- To identify conditions leading to converging wave fronts within splashes.
Main Methods:
- Application of linear response theory to analyze splash dynamics.
- Investigation of the interplay between phase and group velocities.
- Examination of extremal values of velocities and their impact on wave front behavior.
Main Results:
- Splashes result from the interference of collective excitations.
- Extremal phase and group velocities dictate splash features.
- Negative group velocity in a spectral range leads to converging wave fronts.
- Superfluid 4He exhibits splash features determined by five extremal velocities.
Conclusions:
- The study provides a theoretical framework for understanding splashes.
- Converging wave fronts are a key feature in certain splash scenarios, particularly in superfluid 4He.
- The findings are relevant to diverse physical systems, including water surfaces, 2D electron gases, and superfluids.
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