Supercomputer could throw light on 'mysterious' dark energyJanuary 11, 2008Cosmologists have run a series of huge computer simulations of the Universe that could ultimately help solve the mystery of dark energy. Results of the simulations, carried out by Durham University's world-leading Institute for Computational Cosmology (ICC), tell researchers how to measure dark energy - a repulsive force that counteracts gravity. The findings, published today (Friday, January 11) in the Monthly Notices of the Royal Astronomical Society, will also provide vital input into the design of a proposed satellite mission called SPACE - the SPectroscopic All-sky Cosmic Explorer - that could unveil the nature of dark energy. The discovery of dark energy in 1998 was completely unexpected and understanding its nature is one of the biggest problems in physics. Scientists believe dark energy, which makes up 70 per cent of the Universe, is driving its accelerating expansion. If this expansion continues to accelerate experts say it could eventually lead to a Big Freeze as the Universe is pulled apart and becomes a vast cold expanse of dying stars and black holes. The Durham research was funded by the Science and Technology Facilities Council and the European Commission The simulations, which took 11 days to run on Durham's unique Cosmology Machine (COSMA) computer, looked at tiny ripples in the distribution of matter in the Universe made by sound waves a few hundred thousand years after the Big Bang. The ripples are delicate and some have been destroyed over the subsequent 13 billion years of the Universe, but the simulations showed they survived in certain conditions. By changing the nature of dark energy in the simulations, the researchers discovered that the ripples appeared to change in length and could act as a "standard ruler" in the measurement of dark energy. ICC Director Professor Carlos Frenk said: "The ripples are a 'gold standard'. By comparing the size of the measured ripples to the gold standard we can work out how the Universe has expanded and from this figure out the properties of the dark energy. "Astronomers are stuck with the one universe we live in. However, the simulations allow us to experiment with what might have happened if there had been more or less dark energy in the universe." In the next five to 10 years a number of experiments are planned to explore dark energy. The Durham simulation has demonstrated the feasibility of the SPACE satellite mission proposed to the European Space Agency's (ESA) Cosmic Vision programme. The project has been put forward by an international consortium of researchers including the Durham team. SPACE, which is led by Bologna University, in Italy, is through to the next round of assessment by the ESA and if successful is planned to launch in 2017. Co-principal investigator Professor Andrea Cimatti, of Bologna University, said: "Thanks to the ICC simulations it is possible to predict what SPACE would observe and to plan how to develop the mission parameters in order to obtain a three-dimensional map of the Universe and to compare it with the predictions of the simulations. "Thanks to this comparison it will be possible to unveil the nature of dark energy and to understand how the structures in the Universe built up and evolved with cosmic time." Durham University |
|||||||||||||||||||||
| Related Dark Energy Current Events and Dark Energy News Articles ESA spacecraft may help unravel cosmic mystery When Europe's comet chaser Rosetta swings by Earth tomorrow for a critical gravity assist, tracking data will be collected to precisely measure the satellite's change in orbital energy. The results could help unravel a cosmic mystery that has stumped scientists for two decades. Precise picture of early Universe supports 'dark matter' theory A detailed picture of the seeds of structures in the universe has been unveiled by an international team co-led by a Cardiff University scientist. Science at the Petascale: Roadrunner Results Unveiled The world's fastest supercomputer, Roadrunner, at Los Alamos National Laboratory has completed its initial "shakedown" phase doing accelerated petascale computer modeling and simulations of a variety of unclassified, fundamental science projects. Scientists use world's fastest supercomputer to model origins of the unseen universe Understanding dark energy is the number one issue in explaining the universe, according to Salman Habib, of the Laboratory's Nuclear and Particle Physics, Astrophysics and Cosmology group. Vanderbilt astronomers participate in new search for dark energy The most ambitious attempt yet to trace the history of the universe has seen "first light." The Baryon Oscillation Spectroscopic Survey (BOSS), part of the Sloan Digital Sky Survey III (SDSS-III), took its first astronomical data on the night of Sept. 14-15 at the Sloan Foundation telescope in New Mexico. Rebirth of an icon: Hubble's first images since Servicing Mission 4 Astronomers today declared the NASA/ESA Hubble Space Telescope a fully rejuvenated observatory ready for a new decade of exploration, with the release of observations from four of its six operating science instruments. Dark Energy From the Ground Up: Make Way for BigBOSS Several ways have been proposed to examine dark energy, in hopes of finding out just what it is. One of them, "supernovae" for short, certainly works: it's how dark energy was discovered in the first place. Other independent techniques, such as weak gravitational lensing and baryon acoustic oscillation, also promise great power but are as yet unproven. NASA celebrates Chandra X-Ray Observatory's 10th anniversary Ten years ago, on July 23, 1999, NASA's Chandra X-ray Observatory was launched aboard the space shuttle Columbia and deployed into orbit. Radio telescopes extend astronomy's best 'yardstick' Radio astronomers have directly measured the distance to a faraway galaxy, providing a valuable "yardstick" for calibrating large astronomical distances and demonstrating a vital method that could help determine the elusive nature of the mysterious Dark Energy that pervades the Universe. Cosmology's Best Standard Candles Get Even Better Members of the international Nearby Supernova Factory (SNfactory), a collaboration among the U.S. Department of Energy's Lawrence Berkeley National Laboratory, a consortium of French laboratories, and Yale University, have found a new technique that establishes the intrinsic brightness of Type Ia supernovae more accurately than ever before. More Dark Energy Current Events and Dark Energy News Articles |
|||||||||||||||||||||
|
|||||||||||||||||||||
|
|||||||||||||||||||||