| 7 | 11 | The cosmological 21cm signal may prove to be the most powerful probe of the early Universe. This tomographic signal is rich in information, containing both astrophysical and cosmological components. Interpreting this data requires efficient simulation tools, which can overcome the daunting range of relevant scales, as well as our lack of understanding of high-redshift astrophysics. I will introduce "semi-numerical" simulation tools developed for this purpose, which have finally enabled astrophysical parameter studies. I will show how these can be used to make robust predictions of the 21cm signal from the early Universe, focusing on the pre-reionization epochs. These epochs, in which the temperature of the IGM plays a dominant role, serve as a window on the X-ray luminosity of early galaxies, as well as the annihilation and decay signal from dark matter models. |
