The evolution of the Universe has been modeled by supercomputers in the most-detailed simulation of its type ever developed.
Mark Vogelsberger at the Massachusetts Institute of Technology designed the application that models the Universe from shortly after the Big Bang until the present day.
Several independent measurements place the age of the Universe at around 13.8 billion years. Astronomers are still working to ascertain exactly how galaxies formed during that time. These families of stars are not evenly distributed around the Cosmos - they exist on the edges of giant bubbles of empty space. One of the goals of models like this one is to determine how this layout and structure evolved.
Starting 12 million years after the big bang, the new model traces the evolution of large-scale objects, such as galaxies, as well the distribution of gases around the Cosmos, in more detail than ever before. The simulation follows the evolution of 41,416 galaxies, covering an area 350 million light years in length. This is small enough to reveal the growth of galaxies, while remaining large enough to model the entire Cosmos.
One of the challenges of modeling all the matter in the Universe came from the relative lack of ordinary matter throughout the Cosmos. Less than five percent of all matter and energy come in the form of the objects we see around us.
Over 95 percent of the Universe is composed of exotic dark matter and the even more-elusive dark energy. Very little is known about these strange analogs to the matter and energy we see around us every day. Modeling little-understood phenomenon creates obvious problems.
Earlier models did not correctly predict the correct ratio of different shapes of galaxies, something the new simulation managed to achieve.
"Some galaxies are more elliptical and some are more like the Milky Way, [spiral] disc-type galaxies. There is a certain ratio in the universe. We get the ratio right. That was not achieved before," Vogelsberger stated.
The simulation makes a new prediction about the distribution of matter throughout the Universe. According to the new model, supernovas may play an important role in the development and distribution of galaxies.
Images can be extracted from the model, and compared to real-life observations This allows the simulation to act like a virtual telescope, in order to test the model against real-life data.
Although the most advanced simulation of the Universe ever created, there are still inaccuracies in the the simulation. For one, low-mass galaxies form sooner than calculated by physicists.