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A simulated Black Hole with the Milky Way in the backgroundThere is a giant black hole at the centre of our galaxy, a study has confirmed. German astronomers tracked the movement of 28 stars circling the centre of the Milky Way, using the European Southern Observatory in Chile. The black hole is four million times heavier than our Sun, according to the paper in The Astrophysical Journal. Black holes are objects whose gravity is so great that nothing - including light - can escape them. According to Dr Robert Massy, of the Royal Astronomical Society, the results suggest that galaxies...

Science Fiction has a lousy record of predicting the future. In the 1930s, for example, it was widely held that by 1970, toga-clad descendants of the Depression Generation would be living in giant art deco cities full of speeding Dymaxion Cars and dining on food pills. In the '50s and '60s, it was rocket belts and atomic-powered flying cars we were supposed to be enjoying by 2000. And today? In almost every extrapolation of the future I've read lately, the ultimate fate of mankind is uploading -- the transference of consciousness from biological to digital substrates. Such uploads, it is...

Proton discovery may cast doubt on dark-matter theories. The Milagro detector has seen cosmic-ray hot-spots.Milagro / U. Maryland / LANL Hot on the heels of speculation that cosmic rays may have revealed the signature of elusive dark matter in space, new observations could challenge that idea and reinforce an alternative explanation.A seven-year-long experiment at the Milagro cosmic-ray detector near Los Alamos, New Mexico, has revealed 'bright patches' of high-energy cosmic rays in the sky1 – something incompatible with a dark-matter source.Cosmic rays are charged particles, mostly protons and electrons, that are produced in space and generally have a characteristic energy...

Correct calculation strengthens theory of quark-gluon interactions in nuclear particles When it comes to weighty matters, quarks and gluons rule the universe, a new study confirms. One of the largest computational efforts to calculate the masses of protons and neutrons shows that the standard model of particle physics predicts those masses with an uncertainty of less than 4 percent. Christian Hoelbling, affiliated with the Bergische Universtät Wuppertal in Germany, the Eötvös University in Budapest and the CNRS in Marseille, France, and his colleagues report their findings in the Nov. 21 Science. Nearly all the mass of ordinary matter consists of...

ScienceDaily (Sep. 18, 1997) — A team of 20 physicists from four institutions has literally made something from nothing, creating particles of matter from ordinary light for the first time. The experiment was carried out at the Stanford Linear Accelerator Center (SLAC) by scientists and students from the University of Rochester, Princeton University, the University of Tennessee, and Stanford. The team reported the work in the Sept. 1 issue of Physical Review Letters. Scientists have long been able to convert matter to energy; the most spectacular example is a nuclear explosion, where a small amount of matter creates tremendous energy....

« Irradiate a millimeter-thick gold target with the right kind of laser and you might get a surprise in the form of 100 billion positrons, the antimatter equivalent of electrons. Researchers had been studying the process at Lawrence Livermore National Laboratory, where they used thin targets that produced far fewer positrons. The new laser method came about through simulations that showed a thicker target was more effective.And suddenly lasers and antimatter are again making news. Hui Chen is the Livermore scientist behind this work: “We’ve detected far more anti-matter than anyone else has ever measured in a laser experiment....

The Deadbolt: What are your personal views on fringe science? Are you into UFOs, Bigfoot, and things like that? John Noble: Not UFOs, not that. I don't have anything against it, it's just not something that tantalizes my imagination. I think I'm much more fascinated by what we've discovered through quantum mechanics and so forth. What was started off by Albert Einstein, essentially, has just opened the floodgates into a new world and we suddenly find out that we can bend time. And string theory, it just means that anything is conceivable and I find that fascinating. We don't even...

Stanford University physicist Leonard Susskind will discuss his 20-year battle with cosmologist Stephen Hawking over their conflicting interpretations of the behavior of black holes in a lecture at 8 p.m. Thursday, Nov. 20, in McCosh 50. He will describe the clash and the resulting discoveries in a talk titled "The Black Hole War." Susskind, the Felix Bloch Professor of Theoretical Physics at Stanford, is widely regarded as one of the fathers of string theory. His lecture will be based on events and ideas in his newest book, "The Black Hole War: My Battle With Stephen Hawking to Make the World...

WASHINGTON (Reuters) - Astronomers said on Monday they have detected a cosmic explosion at the very edge of the visible universe, a 13-billion-year-old blast that could help them learn more about the earliest stars. The brilliant blast -- known as a gamma ray burst -- was probably caused by the death of a massive star soon after the Big Bang, but was glimpsed on September 4 by NASA's new Swift satellite and later by ground-based telescopes. The explosion occurred soon after the first stars and galaxies formed, perhaps 500 million to 1 billion years after the Big Bang explosion that...

Plans to trace the Moon's orbit with extraordinary new accuracy could reveal kinks in Einstein's theory of gravity and help explain the mysterious accelerating expansion of the universe, says a US researcher. The acceleration cannot be explained by known forces in the Universe. To account for the behaviour, cosmologists have introduced the concept of a new, as yet unseen, force - dark energy. But Gia Dvali, of New York University, US, believes there could be another explanation. He thinks the accelerating expansion might be caused by unexpected properties of gravity, which are only seen over very large distances. Taking inspiration...

Einstein's relativity theory hits a speed bump August 8 2002 Australian scientists have discovered that light isn't quite as fast as it used to be. But it doesn't mean E=mc2 will be consigned to the dustbin, writes David Wroe. In October, 1971, American physicists took four super-accurate atomic clocks, kept two on the ground and put two on commercial jets flying at 1000 kmh in opposite directions around Earth. When the planes landed, the scientists found what they were hoping for: The clocks on the high-speed journeys were ticking a few billionths of a second behind their stationary friends. Motion,...

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...

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...

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...

You can manipulate a black hole as much as you like but you’ll never get rid of its event horizon, a new study suggests. This may sound a little odd, the event horizon is what makes the black hole, well… black. However, in the centre of a black hole, hidden deep inside the event horizon, is a singularity. A singularity is a mathematical consequence, it is also a point in space where the laws of physics do not apply. Mathematics also predicts that singularities can exist without an associated event horizon, but this means that we’d be able to physically...

Enlarge ImageBreaking their way. Makoto Kobayashi (left), Toshihide Maskawa (center), and Yoichiro Nambu share the prize for work on two different aspects of "broken symmetry."Credit: KYODO/Reuters This year's Nobel Prize in physics honors three particle theorist of Japanese origin, one for pioneering the use of a key conceptual tool and the other two for making, in essence, an inspired educated guess that expanded the family of fundamental subatomic particles. Yoichiro Nambu, 87, of the University of Chicago in Illinois receives half the $1.4 million prize for, in the early 1960s, applying to particle physics the concept of spontaneous symmetry...

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.

HONOLULU — A federal judge in Hawaii has dismissed a lawsuit trying to stop the world's largest atom smasher. U.S. District Court Judge Helen Gilmor ruled Friday that federal courts don't have jurisdiction over the Large Hadron Collider in Europe, near Geneva. Two Hawaii residents sued because they feared that the machine could create small black holes or other phenomena that could destroy the planet.

The standard model of cosmology predicts that the universe is infinite and flat. However, cosmologists in France and the US are now suggesting that space could be finite and shaped like a dodecahedron instead. They claim that a universe with the same shape as the twelve-sided polygon can explain measurements of the cosmic microwave background – the radiation left over from the big bang – that spaces with more mundane shapes cannot.Power spectrum of the cosmic microwave background (CMB) radiation. Data from WMAP have extended the accuracy of the spectrum far beyond what was known from earlier measurements. This plot...