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Published on: December 4, 2017
Dielectric function beyond the random-phase approximation: kinetic theory versus linear response theory.
1Universität Rostock, Institut für Physik, 18051 Rostock, Germany. heidi.reinholz@uni-rostock.de
Summary
This study derives the frequency-dependent dielectric function for strongly coupled plasmas, comparing kinetic and linear response theories. It proves the Kohler variational principle extends to arbitrary frequencies, offering a unified approach for plasma physics research.
Area of Science:
- Plasma Physics
- Statistical Mechanics
- Theoretical Physics
Background:
- Calculating the frequency-dependent dielectric function is crucial for understanding plasma behavior.
- Existing methods often have limitations in scope and applicability, particularly for strongly coupled systems.
- Comparing kinetic theory and linear response theory provides insights into different theoretical frameworks.
Purpose of the Study:
- To derive and compare relations within kinetic theory and linear response theory for strongly coupled plasmas.
- To extend the Kohler variational principle to arbitrary frequencies.
- To establish a general approach to linear response theory for improved plasma modeling.
Main Methods:
- Derivation of frequency-dependent dielectric function using kinetic and linear response theories.
- Proof of the extension of the Kohler variational principle to arbitrary frequencies.
- Comparison with the Zubarev method for nonequilibrium statistical operators.
Main Results:
- The Kohler variational principle is shown to be a special case of the Zubarev method.
- The energy-dependent relaxation time approach in kinetic theory is valid only for static Lorentz plasmas.
- Linear response theory, including electron-electron interactions, is applicable for arbitrary frequencies and bremsstrahlung emission.
Conclusions:
- A general approach to linear response theory unifies different approximations for plasma dielectric functions.
- This framework allows for systematic improvements in modeling strongly coupled plasmas.
- The study provides a more comprehensive understanding of plasma behavior across various conditions.
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