News Picks : New simulation of the universe closely matches reality
08 May 2014
Ars Technica: A new simulation of the Lambda–Cold Dark Matter (ΛCDM) model of the universe suggests that inconsistencies in previous simulations were due to their limited size and computational ability, not the model itself. Now researchers have increased the size of the model to represent a cubic volume of space with each side measuring 350 million light-years. In their hydrodynamic simulation, in which pieces of the universe are represented as particles in a fluid, each “particle” had a minimum mass of 1 million solar masses and a minimum diameter of 40 parsecs. The internal behavior and characteristics of each piece were controlled by the ΛCDM model, and the pieces’ behavior could affect that of their neighbors. The simulation, which began with the universe as it would have appeared 12 million years after the Big Bang, was allowed to run for 13 billion years, up to the present. Compared with observations of the oldest known galaxies, the early period of the simulation was very accurate. And unlike previous simulations, the later galaxies of the new simulation formed spiral and elliptical shapes resembling those of real, nearby galaxies. Despite its flaws, the simulation demonstrated that as computing capabilities increase, simulations are likely to improve further.