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Entropy and Variational Formulation of Relativistic Fluid Dynamics
Asher Yahalom1,2,3
1Department of Electrical & Electronic Engineering, Faculty of Engineering, Ariel University, Ariel 40700, Israel.
Entropy (Basel, Switzerland)
|December 24, 2025
Summary
This study extends variational analysis to relativistic non-barotropic flows, introducing a new Eulerian formulation. This method enables the canonical derivation of the energy-momentum tensor for these complex systems.
Area of Science:
- Fluid dynamics
- Relativistic physics
- Variational principles
Background:
- Classical non-barotropic flows lack a comprehensive relativistic variational framework.
- Understanding relativistic fluid dynamics is crucial for astrophysics and high-energy physics.
Purpose of the Study:
- To extend variational analysis to special relativistic non-barotropic flows.
- To develop a new Eulerian variational formulation for these flows.
- To canonically derive the energy-momentum tensor within this relativistic framework.
Main Methods:
- Developed a novel six-function Eulerian variational formulation.
- Applied variational principles to relativistic fluid dynamics.
- Utilized the formulation for canonical derivation of physical quantities.
Main Results:
- Successfully extended variational analysis to the special relativistic non-barotropic regime.
- Established a new Eulerian variational formulation based on six functions.
- Achieved the canonical derivation of the energy-momentum tensor for relativistic non-barotropic flows.
Conclusions:
- The new formulation provides a powerful tool for studying relativistic fluid dynamics.
- This work bridges classical and relativistic fluid dynamics through variational methods.
- The derived energy-momentum tensor is essential for theoretical and computational relativistic fluid dynamics.
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