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Scientists' predictions about the mysterious dark matter purported to make up most of the mass of the Universe may have to be revised.Research on dwarf galaxies suggests they cannot form in the way they do if dark matter exists in the form that the most common model requires it to. That may mean that the Large Hadron Collider will not be able to spot it. Leading cosmologist Carlos Frenk spoke of the "disturbing" developments at the British Science Festival in Bradford. The current theory holds that around 4% of the Universe is made up of normal matter - the stuff...

First results from a major astronomical survey have confirmed the existence of mysterious dark energy using a cutting-edge technique. Dark energy makes up some 74% of the Universe and its existence explains why the Universe appears to be expanding at an accelerating rate. The finding was based on studies of more than 200,000 galaxies. Scientists used two separate kinds of observation to provide an independent check on previous dark energy results. Two papers by an international team of researchers have been accepted for publication in the Monthly Notices of the Royal Astronomical Society journal. One type of observation used by...

Is an Adjacent Universe Causing the Dark Flow of Hundred of Millions of Stars at the Edge of the Observable Universe? Or, Might It Be Something ElseBack in the Middle Ages, maps showed terrifying images of sea dragons at the boundaries of the known world. Today, scientists have observed strange new motion at the very limits of the known universe -- kind of where you'd expect to find new things, but they still didn't expect this. A huge swathe of galactic clusters seem to be heading to a cosmic hotspot and nobody knows why. The unexplained motion has hundreds of...

Researchers have developed a simple technique that adds evidence to the theory that the Universe is flat. Moreover, the method - developed by revisiting a 30-year-old idea - confirms that "dark energy" makes up nearly three-quarters of the Universe. The research, published in Nature, uses existing data and relies on fewer assumptions than current approaches. Author Christian Marinoni says the idea turns estimating the Universe's shape into "primary school" geometry. While the idea of the Earth being flat preoccupied explorers centuries ago, the question of whether the Universe itself is flat remains a debatable topic. The degree to which the...

Today physicists announced that they may have found the key to explaining dark matter in the universe. It all has to do with the potential discovery of a "sterile neutrino." According to a release about the new study: Neutrinos are neutral elementary particles born in the radioactive decay of other particles. The known "flavors" of neutrinos are the neutral counterparts of electrons and their heavier cousins, muons and taus. Regardless of a neutrino's original flavor, the particles constantly flip from one type to another in a phenomenon called "neutrino flavor oscillation." An electron neutrino might become a muon neutrino, and...

British scientists have claimed that the method used to calculate the make-up of the universe may be wrong. The universe as we know it -- formed of recognisable components such as planets, stars, asteroids and gas -- accounts for just four per cent of the cosmos, according to the decades old Standard Model. The rest is thought to be made up of mysterious dark matter and dark energy. This permeates space and powers the expansion of the universe. But physicists at Durham University now claim the calculations on which the Standard Model is based could be fatally flawed. This raises...

Scientists announced Thursday that they believe they have detected evidence of dark matter in data collected at an underground physics lab in Soudan... According to the Department of Energy's Fermilab, which is conducting the search for dark matter at the Soudan lab, "judging by the way galaxies rotate, scientists have known for 70 years that the matter we can see does not provide enough gravitational pull to hold the galaxies together. There must exist some form of matter that does not emit or reflect light." In the announcement, the lab said the Cryogenic Dark Matter Search experiment has "detected...

What if the discrepancy arises from a flaw in our theory of gravity rather than from some provider of mass that we cannot see? In the 1980s physicist Mordehai Milgrom of the Weizmann Institute of Science in Rehovot, Israel, proposed a modification to Newtonian dynamics that would explain many of the observational discrepancies without requiring significant mass to be hidden away in dark matter. But it fell short of describing all celestial objects, and to incorporate the full span of gravitational interactions, a modification to Albert Einstein's theory of general relativity is needed. A review article in the November 6...

Imagine a time when the entire universe froze. According to a new model for dark energy, that is essentially what happened about 11.5 billion years ago, when the universe was a quarter of the size it is today. The model, published online May 6 in the journal Physical Review D, was developed by Research Associate Sourish Dutta and Professor of Physics Robert Scherrer at Vanderbilt University, working with Professor of Physics Stephen Hsu and graduate student David Reeb at the University of Oregon. A cosmological phase transition -- similar to freezing -- is one of the distinctive aspects of this...

As modern cosmologists rely more and more on the ominous "dark matter" to explain otherwise inexplicable observations, much effort has gone into the detection of this mysterious substance in the last two decades, yet no direct proof could be found that it actually exists. Even if it does exist, dark matter would be unable to reconcile all the current discrepancies between actual measurements and predictions based on theoretical models. Hence the number of physicists questioning the existence of dark matter has been increasing for some time now. Competing theories of gravitation have already been developed which are independent of this...

For the past quarter century, dark matter has been a mystery we've just had to live with. But the time may be getting close when science can finally unveil what this befuddling stuff is that makes up most of the matter in the universe. Dark matter can't be seen. Nobody even knows what it is. But it must be there, because without it galaxies would fly apart. Upcoming experiments on Earth such as the Large Hadron Collider (LHC) particle accelerator in Switzerland, and a new spacecraft called Gaia set to launch in 2011, could be the key to closing the...

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...

As if the mysteries of dark matter and dark energy weren't vexing enough, another baffling cosmic puzzle has been discovered. Patches of matter in the universe seem to be moving at very high speeds and in a uniform direction that can't be explained by any of the known gravitational forces in the observable universe. Astronomers are calling the phenomenon "dark flow." The stuff that's pulling this matter must be outside the observable universe, researchers conclude. When scientists talk about the observable universe, they don't just mean as far out as the eye, or even the most powerful telescope, can see....

Tsunami invisibility cloak, dark energy v. the void, sorting nanotubes with light, and moreNews from the American Physical SocietyTsunami Invisibility Cloak M. Farhat, S. Enoch, S. Guenneau and A.B. Movchan Physical Review Letters (forthcoming) Rather than building stronger ocean-based structures to withstand tsunamis, it might be easier to simply make the structures disappear. A collaboration of physicists from the Centre National de la Recherche Scientifique (CNRS) and Aix-Marseille Universite in France and the University of Liverpool in England have conducted laboratory experiments showing that it's possible to make type of dike that acts as an invisibility cloak that hides off-shore...

If the notion of dark energy sounds improbable, get ready for an even more outlandish suggestion. Earth may be trapped in an abnormal bubble of space-time that is particularly void of matter. Scientists say this condition could account for the apparent acceleration of the universe's expansion, for which dark energy currently is the leading explanation.

Nobody knows what dark matter is, but scientists may now have a clue where to look for it. The strange stuff makes up about 85 percent of the heft of the universe. It's invisible, but researchers know it's there because there is not enough regular matter -- stars and planets and gas and dust -- to hold galaxies and galaxy clusters together. Some other unseen material, dubbed dark matter, must be gluing things together... A new computer simulation of the evolution of a galaxy like our Milky Way suggests it might be possible to observe high-energy gamma-rays given off by...

A study of small galaxies circling around the Milky Way found that while they range dramatically in brightness, they all surprisingly pack about the same mass. The work suggests there is a minimum size for galaxies, and it could shed light on mysterious dark matter. Spinning around the Milky Way are at least 23 pint-sized galaxies, each shining with the light of anywhere from a thousand to a billion suns. Though each of these galaxies is very dim compared to large galaxies like our own, they span a large range in brightness. Astronomers led by Louis Strigari of the University...

Everything in the known universe is said to be racing toward the massive clumps of matter at more than 2 million miles (3.2 million kilometers) an hour -- a movement the researchers have dubbed dark flow. The presence of the extra-universal matter suggests that our universe is part of something bigger -- a multiverse -- and that whatever is out there is very different from the universe we know, according to study leader Alexander Kashlinsky, an astrophysicist at NASA's Goddard Space Flight Center in Maryland... Dark flow was named in a nod to dark energy and dark matter -- two...

As if the mysteries of dark matter and dark energy weren't vexing enough, another baffling cosmic puzzle has been discovered. Patches of matter in the universe seem to be moving at very high speeds and in a uniform direction that can't be explained by any of the known gravitational forces in the observable universe. Astronomers are calling the phenomenon "dark flow." The stuff that's pulling this matter must be outside the observable universe, researchers conclude.

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...