![\"Virtualuniverse\"](\"https:\/\/saab.com.bd\/wp-content\/uploads\/2014\/05\/Virtualuniverse.jpg\")
<\/a>\n\u201cUntil now, no single simulation was able to reproduce the universe on both large and small scales simultaneously,\u201d said Mark Vogelsberger from the Harvard-Smithsonian Center for Astrophysics (CfA) in Cambridge, Massachusetts, who conducted the work in collaboration with researchers at several institutions, including the Heidelberg Institute for Theoretical Studies in Germany.<\/p>\n
Previous attempts to simulate the universe were hampered by lack of computing power and the complexities of the underlying physics. As a result, those programs either were limited in resolution or forced to focus on a small portion of the universe. Earlier simulations also had trouble modeling complex feedback from star formation, supernova explosions, and supermassive black holes.<\/p>\n
Illustris employs a sophisticated computer program to recreate the evolution of the universe in high fidelity. It includes both normal matter and dark matter using 12 billion 3-D pixels, or resolution elements.<\/p>\n
The team dedicated five years to developing the Illustris program. The actual calculations took three months of \u201crun time,\u201d using a total of 8,000 CPUs running in parallel. If they had used an average desktop computer, the calculations would have taken more than 2,000 years to complete.<\/p>\n
The computer simulation began a mere 12 million years after the Big Bang. When it reached the present day, astronomers counted more than 41,000 galaxies in the cube of simulated space. Importantly, Illustris yielded a realistic mix of spiral galaxies like the Milky Way and football-shaped elliptical galaxies. It also recreated large-scale structures like galaxy clusters and the bubbles and voids of the cosmic web. On the small scale, it accurately recreated the chemistries of individual galaxies.<\/p>\n
Since light travels at a fixed speed, the farther away astronomers look, the farther back in time they can see. A galaxy 1 billion light-years away is seen as it was a billion years ago. Telescopes like Hubble can give us views of the early universe by looking to greater distances. However, astronomers can\u2019t use Hubble to follow the evolution of a single galaxy over time.<\/p>\n
\u201cIllustris 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\u2019s really going on,\u201d said Shy Genel of the CfA.<\/p>\n
The team is releasing a high-definition video, which morphs between different components of the simulation to highlight various layers, e.g., dark-matter density, gas temperature, or chemistry. They also are releasing several smaller videos and associated imagery online.<\/p>\n
Video Link: http:\/\/www.youtube.com\/watch?v=NjSFR40SY58#t=161<\/a><\/p>\n