Massive Black Holes in Galactic Nuclei

TL;DR

This paper reviews the astrophysical properties, formation, growth, and mergers of massive black holes in galactic nuclei, emphasizing recent theoretical insights and future observational prospects.

Contribution

It provides a comprehensive overview of the current understanding and recent advances in the study of massive black holes in galactic nuclei from a mainly theoretical perspective.

Findings

Relations between black hole mass and host galaxy properties

Formation mechanisms of black holes in the early Universe

Processes of black hole growth and binary coalescence

Abstract

Massive black holes are key inhabitants of the nuclei of galaxies. Moreover, their astrophysical relevance has gained significant traction in recent years, thanks especially to the amazing results that are being (or will be) delivered by instruments such as the James Webb Space Telescope, Pulsar Timing Array projects and LISA. In this Chapter, we aim to detail a broad set of aspects related to the astrophysical nature of massive black holes embedded in galactic nuclei, with a particular focus on recent and upcoming advances in the field. In particular, we will address questions such as: What shapes the relations connecting the mass of massive black holes with the properties of their host galaxies? How do massive black holes form in the early Universe? What mechanisms keep on feeding them so that they can attain very large masses at z = 0? How do binaries composed of two massive black holes form and coalesce into a single, larger black hole? Here we present these topics from a mainly theoretical viewpoint and discuss how present and upcoming facilities may enhance our understanding of massive black holes in the near future.