Bolshoi cosmological simulation

[1] The Bolshoi simulation used the now-standard ΛCDM (Lambda-CDM) model of the universe and the WMAP five-year and seven-year cosmological parameters from NASA's Wilkinson Microwave Anisotropy Probe team.

[7] The Bolshoi-Planck simulation, with the same resolution as Bolshoi, was run in 2013 on the Pleiades supercomputer using the Planck satellite team's cosmological parameters released in March 2013.

Further analysis and comparison with observations by Risa Wechsler's group at Stanford University and others are reflected in the papers based on the Bolshoi simulations.

[10] A successful large-scale simulation of the evolution of galaxies, with results consistent with what is actually seen by astronomers in the night sky, provides evidence that the theoretical underpinnings of the models employed, i.e., the supercomputer implementations ΛCDM, are sound bases for understanding galactic dynamics and the history of the universe, and opens avenues to further research.

[15] The tools provide the initial conditions, including a statistical distribution of positions and velocities of the particles in the ensemble, for the much more demanding Bolshoi simulation of the next approximately 13.8 billion years.

[4] Each snapshot was then analyzed to find all the dark matter halos and the properties of each (particle membership, location, density distribution, rotation, shape, etc.).

[5] The Bolshoi simulation is considered to have produced the best approximation to reality so far obtained for so large a volume of space, about 1 billion light years across.

Starting with initial conditions based on the known distribution of matter shortly after the Big Bang, and using Einstein’s general theory of relativity as the ‘rules’ of the simulation, Bolshoi predicts a modern-day universe with galaxies lining up into hundred-million-light-year-long filaments that surround immense voids, forming a cosmic foam-like structure that precisely matches the cosmic web as revealed by deep galaxy studies such as the Sloan Digital Sky Survey.

Hosting of the Bolshoi outputs and analyses at Leibniz Institute for Astrophysics Potsdam (AIP) is partially supported by the MultiDark grant from the Spanish MICINN Programme.

[7][19] The Icelandic singer-songwriter Björk used footage from the Bolshoi cosmological simulation in the performance of her musical number “Dark Matter” in her Biophilia concert.

Key Cosmological Parameters σ8 and ΩM from Observations Compared with Simulations
Two key cosmological parameters, σ8 and ΩM, with values and 1-σ uncertainties from observations and values used in three cosmological simulations. The parameter σ8 represents the amplitude of the fluctuation spectrum on the scale of clusters of galaxies, and the parameter ΩM is the dark + ordinary matter fraction of the cosmic density. The observations represented by the shapes on the figure are from X-ray and gravitational lensing studies of clusters of galaxies. The observations with error bars are from cosmic microwave background data combined with other data from the Wilkinson Microwave Anisotropy Probe (WMAP) five-year (2009), seven-year (2011), and nine-year (2013) publications and the Planck (2013) data release. The simulations are the Millennium I, II, and XXL simulations (which all used the same cosmological parameters consistent with the WMAP first-year data release 2003), and the Bolshoi (2011) and Bolshoi-Planck (2014) simulations.