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Updated: Apr 15, 2026
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Visually Based Characterization of the Incipient Particle Motion in Regular Substrates: From Laminar to Turbulent Conditions
Published on: February 22, 2018
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Influence of the medium's dimensionality on defect-mediated turbulence
Ghislain St-Yves1, Jörn Davidsen1
1Complexity Science Group, Department of Physics and Astronomy, University of Calgary, Canada T2N 1N4.
Summary
The dimensionality of excitable media significantly impacts defect-mediated turbulence near spiral instabilities, but not in fully developed turbulence. This finding is crucial for understanding complex dynamics in systems like the heart.
Area of Science:
- Nonlinear dynamics
- Complex systems
- Biophysics
Background:
- Spatiotemporal chaos in oscillatory and excitable media is characterized by phase singularities (defects).
- Understanding defect-mediated turbulence and its dependence on system dimensionality is crucial.
- The role of ventricular wall thickness in cardiac fibrillation remains debated.
Purpose of the Study:
- To investigate how changing the dimensionality of an excitable medium from 2D to 3D affects defect-mediated turbulence.
- To determine if changes in turbulent behavior are due to dimensionality or other factors.
- To compare 3D turbulent dynamics with known instabilities like negative line tension.
Main Methods:
- Studied defect-mediated turbulence in a conceptual model of excitable media.
- Compared turbulence in quasi-2D and 3D systems.
- Employed filament tracking to analyze statistical properties.
Main Results:
- Medium thickness had no significant effect on fully developed turbulence, far from onset.
- A clear transition in turbulence occurred near spiral instability when dimensionality changed.
- Observed transition and mechanism change were solely due to dimensionality, not model-specific.
Conclusions:
- Dimensionality is a key factor driving transitions in turbulent dynamics in excitable media.
- 3D turbulent dynamics exhibit distinct statistical properties compared to 2D or filament instability-driven turbulence.
- The observed 3D turbulent dynamics are robust and not limited to specific models.
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