Washington: Astrophysicists have developed a new computational approach that can accurately map the birth and evolution of thousands of galaxies over billions of years. It can also help build a universe from scratch that brims with galaxies.
“We’ve created the full variety of galaxies we see in the local universe,” said Mark Vogelsberger from Harvard-Smithsonian Centre for Astrophysics (CFA), which worked with Heidelberg Institute for Theoretical Studies (HITS) (Germany) on the project.
The Earth’s cosmic neighbourhood is littered with majestic spiral galaxies like Andromeda, Pinwheel and Whirlpool. Spirals are common, but previous simulations had trouble creating them.
Instead, they produced lots of blobby galaxies clumped into balls, without the broad disks and outstretched arms of a typical spiral, said Vogelsberger, according to a CFA and HITS statement.
The new software, called Arepo, solves this problem. Created by Volker Springel of HITS, Arepo generates a full-fledged simulation of the universe, taking as input only the observed afterglow of the Big Bang and evolving forward 14 billion years.
“We took all the advantages of previous codes and removed the disadvantages,” explained Springel.
Our simulations improve over previous ones as much as the Giant Magellan Telescope will improve upon any telescope that exists now,” said Debora Sijacki from CFA.
One of Arepo’s key advantages is the geometry it uses. Previous simulations divided space into a bunch of cubes of fixed sizes and shapes. Arepo uses a grid that flexes and moves in space to match the motions of the underlying gas, stars, dark matter, and dark energy.
Simulations on Harvard’s Odyssey high-performance supercomputer used 1,024 processor cores. This fast machine allowed scientists to compress 14 billion years into a few months, an endeavour that would have kept a desktop computer busy for hundreds of years.