# Numerical galaxy formation and cosmology

## Simulating the universe on a computer

### Benjamin Moster

#### Sommersemester 2018

I will present state-of-the-art techniques for
simulating the formation of galaxies and other cosmic structures on modern supercomputers.
This includes techniques for following the gravitational collapse
of structures, the hydrodynamics and a variety of star formation
and feedback physics. In addition, there will be practical
examples, i.e. simulations that can be performed and analyzed by
the participants on their own laptop computers.

Topics that will be covered:

- Motivation for simulations & Semi-Analytic models
- Initial conditions for simulations
- Gravity algorithms & parallelization
- Hydrodynamics schemes (adaptive mesh refinement, moving-mesh, smoothed
particle hydrodynamics)
- Following radiative cooling & photoheating
- Subresolution physics (star formation, supernova & AGN
feedback)
- Semi-Analytic models
- How to use the Gadget2 code (examples: cosmological box,
galaxy collision)

**Lecture 1** (Apr 11)

topics:

- Introduction to cosmological simulations and semi-analytic
models
- Historical overview

Slides

No Exercise Sheet

**Lecture 2** (Apr 18)

topics:

- The observed Universe
- Basics of Cosmology
- The inhomogeneous Universe

Slides

**Lecture 3** (Apr 18)

topics:

- Creating initial conditions
- The Zel'dovich Approximation
- Creating disc galaxies

Slides

Notes

**The Gadget-2 code**

In the second half of the course we will do some exercises with
the Gadget-2 cosmological simulation code. It can be downloaded
here:

http://www.mpa-garching.mpg.de/gadget/gadget-2.0.7.tar.gz