Astronomers create the first realistic virtual universe

Astronomers create the first realistic virtual universe

Illustris can recreate 13,000 million years of cosmic evolution in a virtual cube of 350 million light years on each side

   A group of astronomers from centers such as the Harvard-Smithsonian or the German Heidelberg Institute have created a virtual universe that would make the Matrix pale. Using a computer simulation named Illustris , these scientists can recreate 13 billion years of cosmic evolution in a cube 350 million light years on each side, all with an unprecedented resolution.

"Until now, no simulation has been able to reproduce the universe on a small and large scale simultaneously," says Mark Vogelsberger, a researcher at MIT and the Harvard-Smithsonian Center for Astrophysics , and lead author of this work, whose results appear in the edition Today's Nature

   Previous attempts to simulate the universe were hampered by the lack of computing power and the complexities of the underlying physics. As a result, those programs were either limited in resolution or forced to concentrate on a small portion of the universe. Previous simulations also had problems modeling the complex feedback system of star formation, supernova explosion, and supermassive black holes.

A time machine

Illustris employs a sophisticated 'software' to recreate the evolution of the universe in high fidelity. It includes both normal matter and dark matter using 12 billion 3D pixels. The team has dedicated five years to develop the program. The real calculations required 3 months of processing time, using a total of 8,000 computers running in parallel. If they had used a normal desktop computer, it would have taken them more than 2,000 years to complete the calculations.

Computer simulation begins just 12 million years after the Big Bang. When they arrived today, these astronomers counted more than 41,000 galaxies in the cube of their simulated space. Illustris succeeded in producing a realistic mixture of spiral galaxies (such as the Milky Way) and ellipticals. It also recreated large-scale structures, such as clusters of galaxies or bubbles and gaps in the cosmic network.

Since light travels at a fixed speed, the farther away astronomers try to look, the further back they can see. A galaxy that is a billion light years away looks like it was a billion years ago. Thanks to telescopes like Hubble, we can obtain a point of view about the origin of the universe, but not follow the evolution of a single galaxy over time.

"Illustris is like a time machine, we can go back and forth in time, we can pause in the simulation and zoom in on a single galaxy or cluster of galaxies to see what is really happening," he says. Shy Genel, also of the Harvard-Smithsonian and co-author of the work.