Cosmology with the Square Kilometre Array

TL;DR

The paper reviews how the Square Kilometre Array (SKA) will advance cosmology by conducting neutral Hydrogen surveys, utilizing innovative aperture arrays, and integrating data across multiple wavebands to address fundamental questions.

Contribution

It provides a comprehensive overview of SKA's capabilities, phases, and its potential to contribute to cosmology through HI surveys and multi-wavelength data integration.

Findings

SKA will significantly enhance neutral Hydrogen surveys in cosmology.

Cross-correlation with other waveband surveys will improve understanding of cosmic phenomena.

SKA's phased development will progressively expand its scientific impact.

Abstract

We review how the Square Kilometre Array (SKA) will address fundamental questions in cosmology, focussing on its use for neutral Hydrogen (HI) surveys. A key enabler of its unique capabilities will be large (but smart) receptors in the form of aperture arrays. We outline the likely contributions of Phase-1 of the SKA (SKA1), Phase-2 SKA (SKA2) and pathfinding activities (SKA0). We emphasise the important role of cross-correlation between SKA HI results and those at other wavebands such as: surveys for objects in the EoR with VISTA and the SKA itself; and huge optical and near-infrared redshift surveys, such as those with HETDEX and Euclid. We note that the SKA will contribute in other ways to cosmology, e.g. through gravitational lensing and $H_{0}$ studies.