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Updated: Jun 13, 2025
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Magnetically Induced Rotating Rayleigh-Taylor Instability
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Causality Bounds on Dissipative General-Relativistic Magnetohydrodynamics.
Ian Cordeiro1, Enrico Speranza1,2, Kevin Ingles1
1Illinois Center for Advanced Studies of the Universe Department of Physics, <a href="https://ror.org/047426m28">University of Illinois Urbana-Champaign</a>, Urbana, Illinois 61801, USA.
Physical Review Letters
|September 13, 2024
Summary
Causality in relativistic magnetohydrodynamics requires nonideal effects to be small, limiting kinetic instabilities. This is vital for accurate plasma simulations near supermassive black holes.
Area of Science:
- Plasma physics
- Relativistic astrophysics
- Fluid dynamics
Background:
- Braginskii's magnetohydrodynamics describes plasma behavior.
- Understanding plasma dynamics near supermassive black holes is crucial.
Purpose of the Study:
- Derive conditions for causality and hyperbolicity in relativistic magnetohydrodynamics.
- Assess the impact of nonideal effects on plasma stability.
Main Methods:
- Analysis of relativistic magnetohydrodynamics with shear, bulk, and heat diffusion.
- Investigation in curved spacetime and the fully nonlinear regime.
Main Results:
- Established necessary and sufficient conditions for causality and strong hyperbolicity.
- Demonstrated that causality constrains nonideal effects and kinetic instabilities.
Conclusions:
- Causality imposes strict limits on nonideal effects in relativistic plasmas.
- Results are essential for validating fluid dynamical simulations in astrophysical contexts.
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