Peering into the Dark (Ages) with Low-Frequency Space Interferometers

Understand

Neutral hydrogen pervades the infant Universe, and its redshifted 21-cm signal allows one to chart the Universe.

• This signal allows one to probe astrophysical processes such as the formation of the first stars, galaxies, (super)massive black holes and enrichment of the pristine gas from z~6 to z~30, as well as fundamental physics related to gravity, dark matter, dark energy and particle physics at redshifts beyond that.
• As one enters the Dark Ages (z>30), the Universe becomes pristine.
• Ground-based low-frequency radio telescopes aim to detect the spatial fluctuations of the 21-cm signal.