Project Details
Abstract
A proper treatment of turbulence still poses one of the most prominent problem areas in theoretical astrophysics. This phenomenon, observed in combustion engines as well as in supernova explosions, in our terrestrial atmosphere as well as in our sun, proved to be highly resistant to a satisfying modeling which is appropriate for the enormous scales in time and length in question. Additionally, the physics involved can be extremely complex. As it is rightly stated in Hillebrandt & Kupka (2009), "Although, in a sense, the dynamics of fluid flows is well understood since about 200 years, described by an innocently looking nonlinear partial differential equation, the Navier-Stokes equation, even giants of modern physics, such as Werner Heisenberg, are quoted saying that the two major unsolved problems of physics are the unification of quantum physics and gravity (on the one hand) and turbulence (on the other)….".
Strong links exist between plasma physics in astrophysics and human needs, mentioning here only space weather and the terrestrial magnetic field. The potential role of thermonuclear fusion as a resource of energy needed on earth would be another example or understanding how our sun works (with backlash on life on earth). Modern astrophysics has the advantage to allow investigating a temperature and density regime, which is barely - or even not at all - accessible in terrestrial laboratories, and hence to investigate important aspects of plasma physics, like convection and its interaction with magnetic fields under extreme conditions.
All these arguments contribute to answer the question why it matters that we understand under which circumstances convection occurs in stars. Furthermore, deficits in our understanding of stellar structure and evolution limit our understanding of the chemical evolution and physical properties of the Milky Way and of other galaxies, with consequences for cosmology. An important scientific goal for the next decade is the detection and analysis of the "first stars" formed in the Universe after the Big Bang. Since it is likely that these first stars were massive and unstable, a better quantitative understanding of stellar models including convection, magnetic fields, opacity problems, etc., will be crucial.
It is the goal of the present project to provide solid observational evidence for turbulent convection and magnetic field effects in plasma, and of their interaction. This evidence shall guide developing and testing numerical and/or analytical techniques used for modeling stellar interiors and evolution.
It is clear that a complete convection theory will not be created in the near future, but the way definitely has to be paved in this direction .
Strong links exist between plasma physics in astrophysics and human needs, mentioning here only space weather and the terrestrial magnetic field. The potential role of thermonuclear fusion as a resource of energy needed on earth would be another example or understanding how our sun works (with backlash on life on earth). Modern astrophysics has the advantage to allow investigating a temperature and density regime, which is barely - or even not at all - accessible in terrestrial laboratories, and hence to investigate important aspects of plasma physics, like convection and its interaction with magnetic fields under extreme conditions.
All these arguments contribute to answer the question why it matters that we understand under which circumstances convection occurs in stars. Furthermore, deficits in our understanding of stellar structure and evolution limit our understanding of the chemical evolution and physical properties of the Milky Way and of other galaxies, with consequences for cosmology. An important scientific goal for the next decade is the detection and analysis of the "first stars" formed in the Universe after the Big Bang. Since it is likely that these first stars were massive and unstable, a better quantitative understanding of stellar models including convection, magnetic fields, opacity problems, etc., will be crucial.
It is the goal of the present project to provide solid observational evidence for turbulent convection and magnetic field effects in plasma, and of their interaction. This evidence shall guide developing and testing numerical and/or analytical techniques used for modeling stellar interiors and evolution.
It is clear that a complete convection theory will not be created in the near future, but the way definitely has to be paved in this direction .
| Status | Finished |
|---|---|
| Effective start/end date | 1/09/10 → 31/08/13 |
Keywords
- Stellar magnetic field
- Stellar convection
- Stellar structure
- Stellar atmosphere
- Asteroseismology
- Stellar pulsation