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PARIS (AFP) – An orbiting observatory has spotted a massive cluster of galaxies in deep space that can only be explained by the exotic phenomenon known as dark energy, the European Space Agency (ESA) said on Monday. Spotted in a scan by ESA's orbiting X-ray telescope XMM-Newton, the cluster's mass is about 1,000 times that of our own galaxy, the Milky Way, it said. The huge cluster, known by its catalogue number of 2XMM J083026+524133, lies 7.7 billion light years from Earth and helps confirm the existence of dark energy, the agency said. Under this hypothesis, most of the Universe...

BALTIMORE — Mario Livio tossed his car keys in the air. They rose ever more slowly, paused, shining, at the top of their arc, and then in accordance with everything our Galilean ape brains have ever learned to expect, crashed back down into his hand. That was the whole problem, explained Dr. Livio, a theorist at the Space Telescope Science Institute here on the Johns Hopkins campus. A decade ago, astronomers discovered that what is true for your car keys is not true for the galaxies. Having been impelled apart by the force of the Big Bang, the galaxies, in...

The Copernican principle states that the Earth is not the center of the universe, and that, as observers, we don’t occupy a special place. First stated by Copernicus in the 16th century, today the idea is wholly accepted by scientists, and is an assumed concept in many astronomical theories.However, as physicists Robert Caldwell of Dartmouth College in Hanover, New Hampshire, and Albert Stebbins of Fermilab in Batavia, Illinois, point out, the Copernican principle has never been confirmed as a whole. In a recent paper published in Physical Review Letters called “A Test of the Copernican Principle,” the two researchers...

A team of Italian and Chinese physicists on Wednesday renewed a controversial claim that they had detected the mysterious dark matter particles that astronomers say swaddle the galaxies in halos and direct the evolution of the universe. The team, called Dama, from “DArk MAtter,” and led by Rita Bernabei of the University of Rome, has maintained since 2000 that a yearly modulation in the rate of flashes in a detector nearly a mile underneath the Gran Sasso mountain in Italy is the result of the Earth’s passage through a “wind” of dark matter particles as it goes around the Sun....

DARK ENERGY DOMINATES THE UNIVERSE HANOVER, NH - A Dartmouth researcher is building a case for a "dark energy"-dominated universe. Dark energy, the mysterious energy with unusual anti-gravitational properties, has been the subject of great debate among cosmologists. Brian Chaboyer, Assistant Professor of Physics and Astronomy at Dartmouth, with his collaborator Lawrence Krauss, Professor of Physics and Astronomy at Case Western Reserve University, have reported their finding in the January 3, 2003, issue of Science. Combining their calculations of the ages of the oldest stars with measurements of the expansion rate and geometry of the universe lead them to conclude...

When a shot is fired, one expects to see a person with a gun. In the same way, whenever a giant star explodes, astronomers expect to see a galaxy of stars surrounding the site of the blast. This comes right out of basic astronomy, since almost all stars in our universe belong to galaxies. Image right: The robotic Palomar 60-inch telescope imaged the afterglow of GRB 070125 on January 26, 2007. Right: An image taken of the same field on February 16 with the 10-meter Keck I telescope reveals no trace of an afterglow, or a host galaxy. The white...

HAVE we hastened the demise of the universe by looking at it? That’s the startling question posed by a pair of physicists, who suggest that we may have accidentally nudged the universe closer to its death by observing dark energy, which is thought to be speeding up cosmic expansion. Lawrence Krauss of Case Western Reserve University in Cleveland, Ohio, and colleague James Dent suggest that by making this observation in 1998 we may have caused the universe to revert to a state similar to early in its history, when it was more likely to end. “Incredible as it seems, our...

To the ancients, exploding stars were bad news. To astronomer Adam Riess, poring over data from a telescope in Chile, it looked like supernovas were still cursed. He and his colleagues were measuring the brightness and distance of supernovas in order to figure out the little matter of whether the universe would end in fire or in ice. Would it halt its expansion and collapse back on itself in a gnab gib (that's the reverse of the big bang, and passes for humor among astronomers) or expand forever, its light and warmth fading into eternal cold and darkness? But when...

Radiation was used to pinpoint the normal matter, while the observation of gravitational lensing was used locate dark matter. Gravitational lensing allows matter to be oberved, even when it does not emit or absorb light, by examining the movement of galaxies as our line of sight passes through the area of interest. Massive objects will distort the image and cause it to move in unexpected directions. Because the normal matter could interact through electromagnetic radiation, it was found to have slowed violently during the collision while the dark matter sailed on through... In the meantime, other astronomers began using gravitational...

The mysterious cosmic presence called dark energy, which is accelerating the expansion of the universe, might be lurking in hidden dimensions of space. The idea would explain how these dimensions remain stable - a big problem for the unified scheme of physics called string theory... quantum vibrations in the vacuum of space (called vacuum energy or the cosmological constant) that could produce repulsive gravity... should either possess a ridiculously high energy density - 122 orders of magnitude larger than are observed - or cancel out to exactly zero. To make them almost-but-not-quite cancel, in agreement with astronomical observations, means fudging...

...More than 100 scientists from across the globe are descending on McMaster University today... just 5 per cent of the universe is made up of matter we've long known about -- atoms, light, etc. The rest is mysterious dark matter (25 per cent) and the more recently discovered dark energy (70 per cent)... "For the first time in the history of man, it's possible to figure out the total energy in the universe, and the big news is that atoms are at most 5 per cent of what's out there," says Cliff Burgess, Mac professor of physics and astronomy, and...

Take one part unidentified goop. Add three parts mysterious energy. Throw in a dash of ordinary atoms. Mix. Compress. Explode. Let expand for 13.7 billion years. It's an absurd recipe, but it's one that makes cosmologists drool. Ten years ago, no one could agree on what the universe is made of, how it is shaped, or what its ultimate fate will be. But less than five years later, long-awaited measurements and one stunning discovery forever transformed our picture of the universe. The resulting model, often called the concordance model, holds that 22 percent of the universe is composed of dark...

The poster child for dark matter, which got a lot of attention last summer, is the Bullet Cluster of galaxies... What's less well known is that the smaller of the two colliding clusters is a cluster in a hurry, zipping along at 4700 kilometers per second... Farrar... and her graduate student Rachael Rosen estimated a few months ago that gravity should have accelerated the cluster to maybe 3000 km/s. Even if the cluster had an improbable combination of elongated shape, high initial velocity, and special viewing geometry, it should move no faster than 3400 km/s. Farrar concluded that some new...

Dark energy - the mysterious force that is speeding up the expansion of the Universe - has been a part of space for at least nine billion years. That is the conclusion of astronomers who presented results from a three-year study using the Hubble Space Telescope. The finding may rule out some competing theories that predict the strength of dark energy changes over time. Dark energy makes up about 70% of the Universe; the rest is dark matter (25%) and normal matter (5%). "It appears this dark energy was already boosting the expansion of the Universe as much as...

Now a group of astronomers using the Hubble Space Telescope have discovered that billions of years before this mysterious antigravity overcame cosmic gravity and sent the galaxies scooting apart like muscle cars departing a tollbooth, it was already present in space, affecting the evolution of the cosmos... The new results, Dr. Riess and others said, provide new clues and place new limits on the nature of dark energy, a mystery that has thrown physics and cosmology into turmoil over the last decade... The data suggest that in fact dark energy has changed little, if at all, over the course of...

NEW YORK - The Hubble Space Telescope has shown that a mysterious form of energy first conceived by Albert Einstein, then rejected by the famous physicist as his "greatest blunder," appears to have been fueling the expansion of the universe for most of its history. This so-called "dark energy" has been pushing the universe outward for at least 9 billion years, astronomers said Thursday. "This is the first time we have significant, discrete data from back then," said Adam Riess, a professor of astronomy at Johns Hopkins University and researcher at NASA's Space Telescope Science Institute. He and several colleagues...

Dark matter and normal matter have been wrenched apart by the tremendous collision of two large clusters of galaxies. The discovery, using NASA's Chandra X-ray Observatory and other telescopes, gives direct evidence for the existence of dark matter. "This is the most energetic cosmic event, besides the Big Bang, which we know about," said team member Maxim Markevitch of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass. These observations provide the strongest evidence yet that most of the matter in the universe is dark. Despite considerable evidence for dark matter, some scientists have proposed alternative theories for gravity where it...

How an alternate theory of the universe exposes the 'war of words' that underlies modern cosmology. Theoretical physicists have recently been frustrated by a bold hypothesis concerning black holes—specifically, that they don't exist. In March, at the 22nd Pacific Coast Gravity Meeting in Santa Barbara, Calif., George Chapline, an applied physicist at Lawrence Livermore National Laboratory, gave a talk based on ideas he's been incubating for several years. His goal: to amend astrophysics by applying theories of dark energy and condensed matter physics. His work reinvents black holes as so-called "dark energy stars," which are what is left over when...

Feb 28, 2006 In the Dark on Matter Fabulous Matter and Energy Since there is no experimental or observable evidence that dark matter exists, is it just a prop for the beleaguered big bang theory? This highly speculative construct is now combined with one just as fabulous--dark energy--to shore up current cosmological dogma.Credit NASA/CXC/M.Weiss Above: Chandra X-Ray Observatory estimates of the “total energy content of the Universe”. Only "normal matter” can be directly detected with telescopes. The rest of the matter and energy is invisible. In the 1930s, astronomers Fritz Zwicky and Sinclair Smith were puzzled by the motions they...

Three cosmic enigmas, one audacious answer 09 March 2006 Exclusive from New Scientist Print Edition Zeeya Merali DARK energy and dark matter, two of the greatest mysteries confronting physicists, may be two sides of the same coin. A new and as yet undiscovered kind of star could explain both phenomena and, in turn, remove black holes from the lexicon of cosmology. The audacious idea comes from George Chapline, a physicist at Lawrence Livermore National Laboratory in California, and Nobel laureate Robert Laughlin of Stanford University and their colleagues. Last week at the 22nd Pacific Coast Gravity Meeting in Santa Barbara,...

Once upon a time -- a bit more than 100 years ago -- many scientists believed that seemingly empty space wasn't empty at all, but was filled with a substance called luminous ether. This mysterious stuff, never seen in any laboratory on Earth, was thought to explain how gravity from one celestial body could affect another. By the end of the 19th century, though, luminous ether had gone the way of countless other scientific misconceptions. Today, another mysterious substance beguiles astronomers, and this one isn't going away. In fact, it's been at the forefront of cosmological theories for decades. It's ...

Painstaking observations of a kind of subatomic dance suggest that the universe may contain a shadowy form of matter that has never been seen directly and is unexplained by standard physics theories, a team of scientists working at Brookhaven National Laboratory on Long Island announced yesterday. The studies appear to confirm similar findings the scientists reported last year. The research involves muons, rare subatomic particles similar to electrons but 207 times as heavy. The work has been controversial, though for reasons that have little to do with the experiment itself. Theorists who are not involved in the research, but whose...

Reprinted from ScienceDaily Magazine ...Source:             NASA/Marshall Space Flight Center Date Posted:    Thursday, August 01, 2002Web Address:   http://www.sciencedaily.com/releases/2002/08/020801080835.htm Chandra Discovers "Rivers Of Gravity" That Define Cosmic Landscape NASA's Chandra X-ray Observatory has discovered part of an intergalactic web of hot gas and dark matter that contains most of the material in the universe. The hot gas, which appears to lie like a fog in channels carved by rivers of gravity, has been hidden from view since the time galaxies formed. "The Chandra observations, together with ultraviolet observations, are a major advance in our understanding of how the universe evolved over the last 10 billion...

Exclusive from New Scientist Hidden extra dimensions are causing measurements of the strength of gravity at different locations on Earth to be affected by the planet's magnetic field, French researchers say. This is a controversial claim because no one has ever provided experimental evidence to support either the existence of extra dimensions or any interaction between gravity and electromagnetism. But lab measurements of Newton's gravitational constant G suggest that both are real. Newton's constant, which describes the strength of the gravitational pull that bodies exert on each other, is the most poorly determined of the constants of nature. The two...

Quantum physics predicts the existence of an underlying sea of zero-point energy at every point in the universe. This is different from the cosmic microwave background and is also referred to as the electromagnetic quantum vacuum since it is the lowest state of otherwise empty space. This energy is so enormous that most physicists believe that even though zero-point energy seems to be an inescapable consequence of elementary quantum theory, it cannot be physically real, and so is subtracted away in calculations. A minority of physicists accept it as real energy which we cannot directly sense since it is the...

Extra Dimensions Showing Hints Of Scientific Revolution Chicago - Feb 19, 2003 The concept of extra dimensions, dismissed as nonsense even by one of its earliest proponents nearly nine decades ago, may soon help solve seemingly unrelated problems in particle physics, cosmology and gravitational physics, according to a panel of experts who spoke Feb. 15 at the American Association for the Advancement of Science annual meeting in Denver. "It doesn't happen often that you get a confluence of ideas and experiments that come together and it's something that obviously would change your whole way of looking at the universe,"...

Florida Physicist Says Dark Matter, Extra Dimensions Related And Possibly Detectable the universe is the "twilight zone" Gainesville -May 19, 2003 A team of scientists that includes a University of Florida physicist has suggested that two of the biggest mysteries in particle physics and astrophysics -- the existence of extra time and space dimensions and the composition of an invisible cosmic substance called dark matter -- may be connected. "For the most part, these two questions have been treated separately in the past, and for the first time we're making a direct link," said Konstantin Matchev, a UF assistant...

Thursday, 6 September, 2001, 10:39 GMT 11:39 UK Universe 'could condense into jelly' By BBC News Online's Helen Briggs The Universe may be in a state where matter could disintegrate at any moment, a scientist has warned. But the probability is less than that of buying two lottery tickets in the same week that both win the lottery, said Dr Benjamin Allanach of the European laboratory for particle physics, CERN, in Geneva. "The fact that the Universe has existed for 15 billion years should tell you it's not likely to happen tomorrow," he told the British Association Festival of Science ...

...The proposal bears an odd parallel to another modified-gravity theory that has emerged in recent years, and which seeks to explain another dark entity: "dark matter." Not unlike dark energy, dark matter is an unseen substance that astronomers believe pervades the cosmos, but it is different. Dark matter, which would comprise more than 90% of the weight of the universe, is thought to betray its existence through its gravitational pull on nearby objects. Somewhat similarly to what is happening with dark energy, some cosmologists have also devised modified-gravity theories in past years to explain these phenomena.

Contrary to all expectations, the mysterious dark energy that is pushing the Universe apart may be changing with time. By observing distant, powerful bursts of gamma rays (gamma-rays), Brad Schaefer says he has preliminary evidence that the strength of dark energy is different today from when the Universe was very young. Schaefer, an astronomer at Louisiana State University in Baton Rouge, presented his results at an American Astronomical Society meeting in Washington DC. Just minutes after the data were presented in a late afternoon session, some astronomers were already calling the bold claim into question. An idea that arose in...

Volume-holographic optical imaging instrument with the capability to return three-dimensional spatial as well as spectral information about semi-translucent microscopic objects in a single measurement is in use in different parts of the world for the last three years. The four-dimensional volume-holographic microscope is characterized theoretically and experimentally by use of fluorescent micro-spheres as objects. According to some scientists working under classified projects these special instruments are revealing secrets of the nature that can be totally bizarre to our knowledge of science and technology. These four-dimensional volume-holographic optical imaging instrument with the capability to return three-dimensional spatial as well as spectral...

What is the mysterious dark energy that's causing the expansion of the universe to accelerate? Is it some form of Einstein's famous cosmological constant, or is it an exotic repulsive force, dubbed "quintessence," that could make up as much as three-quarters of the cosmos? Scientists from Lawrence Berkeley National Laboratory (Berkeley Lab) and Dartmouth College believe there is a way to find out. n a paper to be published in Physical Review Letters, physicists Eric Linder of Berkeley Lab and Robert Caldwell of Dartmouth show that physics models of dark energy can be separated into distinct scenarios, which could be...

ROME (Reuters) - A small group of physicists are battling what they see as the cosmological equivalent to the bogeyman: an enormous dark force, that nobody has ever seen, driving galaxies apart. Conventional wisdom holds that the mysterious force, called "dark energy," may make up 70 percent of the universe, and could be the determining factor in whether it is eventually destroyed billions of years from now. But Italian and American cosmologists are offering a controversial alternative to explain the accelerating expansion of the universe. They say it's not dark energy, but an overlooked after-effect of the "Big Bang" --...

Giant space-time ripples may cause cosmic expansion* 17:43 18 March 2005 * NewScientist.com news service * Maggie McKee Dark energy is not necessary to explain the accelerating expansion of the universe observed by astronomers, suggest controversial new calculations. Instead, gigantic ripples in space-time - larger than the observable universe - may be the cause. Astronomers have known since the 1920s that space itself has been expanding since the big bang about 14 billion years ago. But in 1998, they discovered the expansion must have sped up about a billion years ago, based on observations of supernovae that appeared farther away...

Why is the universe expanding at an accelerating rate, spreading its contents over ever greater dimensions of space? An original solution to this puzzle, certainly the most fascinating question in modern cosmology, was put forward by four theoretical physicists, Edward W. Kolb of the U.S. Department of Energy's Fermi National Accelerator Laboratory, Chicago (USA): Sabino Matarrese of the University of Padova; Alessio Notari from the University of Montreal (Canada); and Antonio Riotto of INFN (Istituto Nazionale di Fisica Nucleare) of Padova (Italy). Their study was submitted yesterday to the journal Physical Review Letters. Over the last hundred years, the expansion...

WASHINGTON, D.C. - Scientists may not have to go over to the dark side to explain the fate of the universe.The theory that the accelerated expansion of the universe is caused by mysterious "dark energy" is being challenged by New York University physicist Georgi Dvali. He thinks there's just a gravity leak.Scientists have known since the 1920s that the universe is expanding. In the late 1990s, they realized that it is expanding at an ever-increasing pace. At a loss to explain the stunning discovery, cosmologists blamed it on dark energy, a newly coined term to describe the mysterious antigravity force...

Big bang sound waves explain galaxy clustering 13:32 12 January 2005 NewScientist.com news service Maggie McKee, San Diego Sound waves that roared through space after the big bang left behind a subtle imprint in the way galaxies are clustered today, reveal two major studies. The results bolster the standard theory that the universe is flat, and measuring the distance between the sound ripples may provide a new cosmic yardstick to probe the past. Two independent teams mapping the universe have found that galaxies are currently huddled together slightly more often at distances of 500 million light years as a...

You can breathe a sigh of relief: the Universe will last for at least the next 24 billion years, according to astrophysicists who have modelled the mysterious force of dark energy to work out the fate of the cosmos. Andrei Linde, a theoretical astrophysicist from Stanford University, California, leads a team who previously predicted that the Universe might end as soon as 11 billion years from now1. But the team's latest research into dark energy, published online at the preprint server arXiv2, gives us a stay of execution. The team's new calculation relies on recent observations from the Hubble Space...

Two of the biggest physics breakthroughs during the last decade are the discovery that wispy subatomic particles called neutrinos actually have a small amount of mass and the detection that the expansion of the universe is actually picking up speed. Now three University of Washington physicists are suggesting the two discoveries are integrally linked through one of the strangest features of the universe, dark energy, a linkage they say could be caused by a previously unrecognized subatomic particle they call the "acceleron." Dark energy was negligible in the early universe, but now it accounts for about 70 percent of the...

In the last few decades, scientists have discovered that there is a lot more to the universe than meets the eye: the cosmos appears to be filled with not just one, but two invisible constituents –dark matter and dark energy – whose existence has been proposed based solely on their gravitational effects on ordinary matter and energy. Now, theoretical physicist Robert J. Scherrer has come up with a model that could cut the mystery in half by explaining dark matter and dark energy as two aspects of a single unknown force. His model is described in a paper titled “Purely...

The day before the Iowa primary, none of the major news organizations was remotely close to right about what would happen. This isn't stopping the media from predicting what will happen in billions of years! Last week on Tuesday, The New York Times declared that the universe could be torn out of existence in an ultimate cataclysm in as little as "a few billion years." Then, on Saturday, the paper backed down--maybe the Times received an angry letter to the editor from God!--and hedged, declaring "the universe may have a more peaceful end than recent theories envision." The cosmos, the...

WASHINGTON (AP) _ Proof that a mysterious force called ``dark energy'' is pushing the universe to expand endlessly at a faster and faster rate has been selected as the ``Breakthrough of the Year'' by the editors of Science magazine. The bizarre idea that some unknown force exists in the universe that is opposing gravity and flinging galaxies away from each other at an accelerating clip was first proposed in 1998. New studies in 2003 proved that the force does exist and this discovery captured the top prize by the editors of Science as the year's most important scientific development. ``It...

CLEVELAND - (KRT) - The day may come, some cosmologists fear, when they'd be better off as cosmetologists. You know the difference, of course. Cosmetologists are experts at makeup. Cosmologists are experts at making up stories about the universe. For many decades, at least, cosmologists couldn't do much more than make up stories. After the birth of scientific cosmology early in the last century, cosmologists based their theories on next to nothing, other than Einstein's equations for gravity and the observation that the universe seemed to be expanding. In the mid-1960s, though, radiotelescopes detected a faint glow of radiation in...

Measurements of 11 exploding stars spread throughout the visible universe made by the Hubble Space Telescope confirm earlier, ground-based studies which produced the first evidence that the universe is not only expanding, but expanding at an increasing rate. The new study, which has been posted online HERE and will soon appear in the Astrophysical Journal, also provides some tantalizing new insights into the nature of the mysterious repulsive force, dubbed dark energy, that appears to be propelling this run-away expansion. "As far as the ultimate fate of the universe goes, the most straightforward conclusion is that over the next few...

<p>WASHINGTON - In ``Star Wars,'' Darth Vader rules the ``dark side'' of a fantasy universe. In real life, astronomers are exploring the ``dark side'' of our own universe. They find it a mystifying place.</p> <p>According to a batch of new reports published in a special ``Welcome to the Dark Side'' issue of the journal Science, most of the cosmos cannot be seen, even with the most powerful telescopes. All but a tiny fraction of creation consists of two exotic, invisible ingredients called ``dark energy'' and ``dark matter.''</p>

<p>The creative bookkeeping at some accounting-challenged firms is nothing compared with what cosmologists must do to balance the universe's ledgers. But thanks to their efforts to make the numbers come out right, these scientists have stumbled on an improbable coincidence: The amount of a mysterious energy that seems to pervade the cosmos is precisely what is needed to allow for the emergence of stars, planets and life itself.</p>

Astronomy Picture of the Day Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer. 2002 September 17 A Force from Empty Space: The Casimir Effect Credit & Copyright: Umar Mohideen (U. California at Riverside) Explanation: This tiny ball provides evidence that the universe will expand forever. Measuring slightly over one tenth of a millimeter, the ball moves toward a smooth plate in response to energy fluctuations in the vacuum of empty space. The attraction is known as the Casimir Effect, named for...

Looking Backward In Time At How Galaxies Clustered The universe appears to be permeated with an invisible force -- dark energy -- that is pushing it apart faster and faster. By conducting redshift surveys of galaxy clusters, astronomers hope to learn more about this mysterious force, and about the structure and geometry of the universe. "Galaxy clusters consist of thousands of galaxies gravitationally bound into huge structures," said Joseph Mohr, a professor of astronomy at the University of Illinois. "Because of the expansion of the universe, the clusters appear denser at larger redshifts, when the universe was younger and denser."...