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Dark energy -- 10 years on
November 30, 2007Three quarters of our universe is made up of some weird, gravitationally repulsive substance that was only discovered ten years ago - dark energy. This month in Physics World, Eric Linder and Saul Perlmutter, both at the University of California at Berkeley, reveal how little we know about dark energy and describe what advances in our knowledge of dark energy we can expect in the coming decade from a series of planned space missions.
Perlmutter was the leader of one of the two separate teams of astrophysicists who concluded, from watching distant supernovae, that the cosmic expansion was accelerating and not slowing under the influence of gravity, as was previously thought. The two teams' finding confirmed just how little we know about our universe.
The two teams' discovery has led to the creation of the "concordance model" of the universe, which states that 75 per cent of our universe is made up of dark energy, 21 per cent of dark matter, another substance we know little about, with only a remaining four per cent being made up of matter that we do understand. The most conventional explanation is that dark energy is some kind of "cosmological constant" that arises from empty space not being empty, but having an energy as elementary particles pop in and out of existence.
Since the first evidence for the accelerating universe was made public in early 1998, astrophysicists have provided further evidence to shore up the findings and advances in the measurement methods bode well for increasing our understanding in the future.
Galaxies and the cosmic background hold some significant clues. Equipment that can make a more robust comparison between galaxy patterns across the sky and investigate temperature fluctuations in the cosmic microwave background, helping trace the pattern of galaxy formation, is being made available. Methods for further observation of supernovae are expanding and improving too.
Eric Linder and Saul Perlmutter write, "The field of dark energy is very young and we may have a long and exciting period of exploration ahead before it matures."
The December issue also includes reporting from Robert P Crease, historian at the Brookhaven National Laboratory, US, on the difficulty of deciding who should gain credit for the discovery of the accelerating universe and comment from Lawrence M Krauss, director of the Center for Education and Research in Cosmology and Astrophysics at Case Western Reserve University, US, on the possibility that we may never be able to tell if dark energy is a cosmological constant or something more exotic still.
Also in this issue:
* 50 years on: why physicists still love the computer-programming language Fortran
* Christmas books: a round-up of all the best new physics titles for the holiday period
Institute of Physics
Since the first evidence for the accelerating universe was made public in early 1998, astrophysicists have provided further evidence to shore up the findings and advances in the measurement methods bode well for increasing our understanding in the future.
Galaxies and the cosmic background hold some significant clues. Equipment that can make a more robust comparison between galaxy patterns across the sky and investigate temperature fluctuations in the cosmic microwave background, helping trace the pattern of galaxy formation, is being made available. Methods for further observation of supernovae are expanding and improving too.
Eric Linder and Saul Perlmutter write, "The field of dark energy is very young and we may have a long and exciting period of exploration ahead before it matures."
The December issue also includes reporting from Robert P Crease, historian at the Brookhaven National Laboratory, US, on the difficulty of deciding who should gain credit for the discovery of the accelerating universe and comment from Lawrence M Krauss, director of the Center for Education and Research in Cosmology and Astrophysics at Case Western Reserve University, US, on the possibility that we may never be able to tell if dark energy is a cosmological constant or something more exotic still.
Also in this issue:
* 50 years on: why physicists still love the computer-programming language Fortran
* Christmas books: a round-up of all the best new physics titles for the holiday period
Institute of Physics
Dark Energy Current Events and Dark Energy News RSSESA 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
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Dark Side of the Universe: Dark Matter, Dark Energy, and the Fate of the Cosmos by Iain Nicolson (Author) Once we thought the universe was filled with shining stars, dust, planets, and galaxies. We now know that more than 98 percent of all matter in the universe is dark. It emits absolutely nothing yet bends space and time; keeps stars speeding around galaxies; and determines the fate of the universe. But dark matter is only part of the story. Scientists have recently discovered that the expansion of the universe is speeding up, driven by a mysterious commodity called dark energy. Depending on what dark matter and energy happen to be, our seemingly quiet universe could end its days in a Big Rip, tearing itself apart, or a Big Crunch, collapsing down to a universe the size of nothing, ready to be reincarnated in a Big Bang once again. For the general reader and armchair... |
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Dark Matters: Unifying Matter, Dark Matter, Dark Energy, and the Universal Grid by Dr. Percy Seymour (Author) One of the most important unsolved problems of current physics, astronomy, and cosmology is the nature of dark matter and dark energy. These two invisible components of the universe seem to control the behavior of galaxies, clusters of galaxies, and the accelerating expansion of the universe, but we do not know what they are. Dark Matters offers a unified explanation for dark matter and dark energy, and, in doing so, formulates a new theory of ordinary matter. Central to this new theory is the concept of electric lines of force, encased in something called insulating space, which means we are generally not aware of them, just as we are not aware of the currents passing through insulated cables. The essential feature of Dark Matters that sets it apart from similar... |
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Interstellar Pianos by Dark Energy | |
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YuGiOh Elemental Energy Broww, Huntsman of Dark World EEN-EN021 Rare by Upper Deck YuGiOh Elemental Energy - Elemental Energy Single Cards! If this card is discarded from the hand to the Graveyard by a card effect, draw 1 card from your Deck. If this card is discarded from the hand to the Graveyard by your opponent's card effect, draw 1 more card from your Deck. |
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Einstein's Telescope: The Hunt for Dark Matter and Dark Energy in the Universe by Evalyn Gates (Author) Cutting-edge astrophysics that builds on Einstein's theories to find the unseen matter that fills the Universe. Dark energy. Dark matter. These strange and invisible substances don't just sound mysterious: their unexpected appearance in the cosmic census is upending long-held notions about the nature of the Universe. Astronomers have long known that the Universe is expanding, but everything they could see indicated that gravity should be slowing this spread. Instead, it appears that the Universe is accelerating its expansion and that something stronger than gravity--dark energy--is at work. In... |
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Dark Circle Directed By: Judy Irving, Chris Beaver, Ruth Landy Winner of the Grand Prize at the Sundance Film Festival and recipient of a national Emmy Award, DARK CIRCLE follows the trail of plutonium from the Rocky Flats Nuclear Weapons facility in Colorado, to the Diablo Canyon Nuclear Power Plant in California, to Hiroshima and Nagasaki in Japan. |
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Dark Energy (Oscillator Dub) Kevin Freeman & Hypno (Primary Contributor) |
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