The aim of this conference is discuss the beginnings and formation of the largest gravitationally-bound structures in the Universe.

Rationale:

Proto-clusters, high redshift galaxy clusters, and merging clusters represent the initial stages in the formation of largest gravitationally-bound structures in the Universe. Forming via mergers and accretion, (proto-)cluster assembly has a decisive impact on their subsequent evolution, and is thus an important process to understand. The aim of GCF2021 is to discuss cluster formation over the last roughly ten billion years, from its beginnings to the present day, with a particular focus on the progress and developments since our first GCF meeting in 2017.

This is a golden age to study assembling clusters and proto-clusters. Several new facilities covering the entire electromagnetic spectrum have just been completed, are being commissioned now, or are in the advanced planning phase.