Introduction to theoretical Astro Physics

• Existence of cosmic structures on different scales:  compact bodies, stars, galaxies, galaxy clusters.
• Energy equilibria as fundamental principle for dimensional estimates of cosmic objects.
• Gravity, equations of motion for systems of masses, elementary laws in gravitating systems.
• Applications: dynamics of binary systems, galaxies, accreting objects.
• Equations of stellar structure.
• Example: Properties of white dwarfs; Chandrasekhar mass.
• Basic principles of stellar evolution; properties of stars; derivation of scaling relations.
• Mass transfer in binary systems; accretion phenomena; Eddington luminosity.
• Elementary fluid dynamics: basic equations.
• Application of hydrodynamics: shock waves and contact discontinuities; Sedov solution for explosions.
• Introduction to radiation transport:  basic quantities and equations; derivation of diffusion law.
• Radiation processes and neutrino reactions in dense and hot stellar plasmas.
• Astrophysical plasmas:  elementary thermodynamics and equations of state.

For each of these theoretical topics and concepts astrophysical examples will be discussed, e.g. stars, binary stars, galaxies, black holes, the early universe.

After successful participation in the module the student has attained the following abilities. The student can

1. name the observed cosmic structures on different scales and their basic properties.
2. explain the fundamental reasons for the existence of these objects on discrete scales.
3. reflect the fundamental dynamical laws in gravitating systems.
4. explain astrophysical methods for mass determination and apply them to argue in support of the existence of dark matter.
5. describe the basic properties of stars and of stellar evolution towards the final stages.
6. derive elementary scaling relations from differential equations (e.g. of stellar structure).
7. sketch the basic equations of hydrodynamics and their meaning.
8. discriminate between different discontinuities in fluid/plasma flows.
9. name the basic equations of radiative transfer and derive from them the diffusion equation.
10. summarize elementary limiting cases for equations of states of stellar plasmas and apply them to specific cosmic objects.

At least four semesters of physics Bachelor study.

In classroom lectures the teaching and learning content is presented and explained in a didactical, structured, and comprehensive form. This includes mainly elementary basic knowledge from the extremely broad field of theoretical astrophysics, spiced also by selected examples of current research topics. Universal methodic and physics concepts are highlighted by cross referencing between different topics. Crucial facts are conveyed by involving the students in scientific discussions to develop their intellectual power and to stimulate their analytic thinking on physics problems. Regular attendance of the lectures is therefore highly recommended.

The presentation of the learning content is enhanced by problem examples and calculations that the students should work on on a voluntary basis. These examples are intended to deepen the students' understanding and to help their learning of the course material. They can be discussed with the teacher upon request.

The examples as well as regular self-study of personal notes from the lectures and of textbooks and recent review articles referenced in the course are an important part of the learning process by the students. Such post-processing and practising of the teaching content is indispensable to achieve the intended learning results that the students develop the ability of explaining and applying the learned knowledge independently.

Black board teaching, overhead slides, notes and online material, in some cases also projection of visualizations from laptop.

Text books:

• T. Padmanabhan: Theoretical Astrophysics, Vol. I-III, Cambridge Univ. Press
• A. Unsöld & B. Baschek: The new Cosmos, Springer, Berlin
• S.L. Shapiro & S.A. Teukolsky: Black Holes, White Dwarfs, & Neutron Stars, John Wiley & Sons
• M. Bartelmann, Theoretical Astrophysics -- an Introduction, Wiley-VCH, Weinheim

Available notes (in German):

• http://wwwmpa.mpa-garching.mpg.de/lectures/WDNSBH/
• http://wwwmpa.mpa-garching.mpg.de/lectures/TASTRO_SS08/
• http:/wwwmpa.mpa-garching.mpg.de/lectures/HYDRO/

There will be an oral exam of 30 minutes duration. Therein the achievement of the competencies given in section learning outcome is tested exemplarily at least to the given cognition level using Comprehension questions, reflection of simple formulas for the description of elementary relations, and sample calculations for order-of-magnitude estimates.

For example an assignment in the exam might be:

• Name observed cosmic objects on different scales and of their elementary properties.
• Explain why astrophysical structures exist on specific, discrete cosmic scales.
• Summarize methods for astrophysical mass determination and apply them to the problem of Dark Matter.
• Describe elementary properties and evolution tracks of stars based on scaling relations.
• Describe basic equations of fluid dynamics and of their physical meaning.
• Explain different discontinuities in fluid flows and name corresponding astrophysical examples.
• Describe the radiation transport equation and summarize the derivation of the diffusion equation.
• Summarize the basic limiting cases for the equation of state of astrophysical plasmas and corresponding examples of applications.