title: Properties of galaxies reproduced by a hydrodynamic simulation.
abstract: Previous simulations of the growth of cosmic structures have broadly reproduced the 'cosmic web' of galaxies that we see in the Universe, but failed to create a mixed population of elliptical and spiral galaxies, because of numerical inaccuracies and incomplete physical models. Moreover, they were unable to track the small-scale evolution of gas and stars to the present epoch within a representative portion of the Universe. Here we report a simulation that starts 12 million years after the Big Bang, and traces 13 billion years of cosmic evolution with 12 billion resolution elements in a cube of 106.5 megaparsecs a side. It yields a reasonable population of ellipticals and spirals, reproduces the observed distribution of galaxies in clusters and characteristics of hydrogen on large scales, and at the same time matches the 'metal' and hydrogen content of galaxies on small scales.
authors.affiliation: Department of Physics, Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA.
authors.forename: M
authors.initials: M
authors.lastname: Vogelsberger
authors.affiliation: Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, Massachusetts 02138, USA.
authors.forename: S
authors.initials: S
authors.lastname: Genel
authors.affiliation: 1] Heidelberg Institute for Theoretical Studies, Schloss-Wolfsbrunnenweg 35, 69118 Heidelberg, Germany [2] Zentrum für Astronomie der Universität Heidelberg, ARI, Mönchhofstrasse 12-14, 69120 Heidelberg, Germany.
authors.forename: V
authors.initials: V
authors.lastname: Springel
authors.affiliation: Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, Massachusetts 02138, USA.
authors.forename: P
authors.initials: P
authors.lastname: Torrey
authors.affiliation: Kavli Institute for Cosmology, and Institute of Astronomy, Madingley Road, Cambridge CB3 0HA, UK.
authors.forename: D
authors.initials: D
authors.lastname: Sijacki
authors.affiliation: Heidelberg Institute for Theoretical Studies, Schloss-Wolfsbrunnenweg 35, 69118 Heidelberg, Germany.
authors.forename: D
authors.initials: D
authors.lastname: Xu
authors.affiliation: Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, Maryland 21218, USA.
authors.forename: G
authors.initials: G
authors.lastname: Snyder
authors.affiliation: Institute for Advanced Study, 1 Einstein Drive, Princeton, New Jersey 08540, USA.
authors.forename: S
authors.initials: S
authors.lastname: Bird
authors.affiliation: Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, Massachusetts 02138, USA.
authors.forename: D
authors.initials: D
authors.lastname: Nelson
authors.affiliation: Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, Massachusetts 02138, USA.
authors.forename: L
authors.initials: L
authors.lastname: Hernquist