The study of the smallest collapsed structures in the Universe is a fascinating topic for many different reasons:
- In Cold and Warm dark matter cosmologies these objects are the first luminous objects that form in the Universe and constitute the building blocks of today's galaxies. Hence their study holds the key to understanding the formation of the first galaxies and the first stars.
- The nature of the dark matter is still unknown, but different dark matter candidates typically start to show diverging effects on galaxy formation at the scale of the smallest mass galaxies. Hence, the study of small scale structures and dwarf galaxies may also hold the key to unveil the nature of dark matter.
I will present some work done over the past years by my research group on testing the nature of dark matter and constraining star formation in the first galaxies using observations of nearby dwarf galaxies.