# Dark Matter and Galaxy Formation

## TL;DR

This paper reviews the role of dark matter in galaxy formation, discussing historical context, challenges to the LambdaCDM model, observational data, and semi-analytic modeling approaches.

## Contribution

It provides a comprehensive summary of dark matter's influence on galaxy formation and the current challenges faced by the LambdaCDM paradigm.

## Key findings

- LambdaCDM explains large-scale structure formation
- Small-scale challenges include satellite counts and cusp-core issues
- Semi-analytic models help interpret galaxy evolution data

## Abstract

The four lectures that I gave in the XIII Ciclo de Cursos Especiais at the National Observatory of Brazil in Rio in October 2008 were (1) a brief history of dark matter and structure formation in a LambdaCDM universe; (2) challenges to LambdaCDM on small scales: satellites, cusps, and disks; (3) data on galaxy evolution and clustering compared with simulations; and (4) semi-analytic models. These lectures, themselves summaries of much work by many people, are summarized here briefly.