Structure formation

Astrophysical models for the formation of galaxies and clusters of galaxies

In physical cosmology, structure formation describes the creation of galaxies, galaxy clusters, and larger structures via gravitational and hydrodynamic processes operating on cosmological inhomogeneities. The universe, as is now known from observations of the cosmic microwave background radiation, began in a hot, dense, nearly uniform state approximately 13.8 billion years ago. However, looking at the night sky today, structures on all scales can be seen, from stars and planets to galaxies.

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