First realistic virtual universe created

Move over Matrix, astronomers have created the first realistic virtual simulation of the universe, tracking 13 billion years of cosmic evolution.
The newly-developed computer simulation enables researchers to understand how galaxies, black holes and other cosmic phenomena evolved.
The simulation, known as Illustris, follows the complex development of both normal and dark matter over 13 billion years, matching many of the features observed in the real universe for the first time.
Illustris tracks the development of the universe from 12 million years after the Big Bang up to the present, and identified more than 41,000 galaxies in a cube of simulated space 350 million light years on each side.

Over the past two decades, researchers have been attempting to build accurate computer simulations of the development of the universe, using computer programmes which are capable of encapsulating all the relevant laws of physics governing the formation of galaxies.
Illustris employs a sophisticated computer programme to recreate the evolution of the universe in high fidelity. It includes both normal matter and dark matter using 12 billion 3D "pixels," or resolution elements.

Illustris yields a realistic mix of spiral galaxies like the Milky Way and giant elliptical galaxies. It also recreated large-scale structures like galaxy clusters and the bubbles and voids of the cosmic web.

The team dedicated five years to developing the Illustris project. The actual calculations took three months of run time, using a total of 8,000 CPUs running in parallel.
"Until now, no single simulation was able to reproduce the Universe on both large and small scales simultaneously," says lead author Dr Mark Vogelsberger of the Massachusetts Institute of Technology and Harvard University.
"The Illustris simulation is a remarkable technical achievement," said Dr Debora Sijacki of Cambridge University's Institute of Astronomy, one of the paper's co-authors.
"It shows us for the first time how the bewildering variety of galaxies and the super-massive black holes at the centre of our Universe have formed," said Sijacki.

Since light travels at a fixed speed, the farther away astronomers look, the farther back in time they can see. A galaxy one billion light-years away is seen as it was a billion years ago.
"Illustris is like a time machine. We can go forward and backward in time. We can pause the simulation and zoom into a single galaxy or galaxy cluster to see what's really going on," said co-author Dr Shy Genel of Harvard University.
The results are reported in the journal Nature.