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For you physics lovers - this is really clever!

Neil Turok, professor of mathematical physics at Cambridge University. He is the co-author of the new book, "Endless Universe: Beyond the Big Bang."Alan Guth, professor of physics at the Massachusetts Institute of Technology. He is the author of "The Inflationary Universe: The Quest for a New Theory of Cosmic Origins."Janna Levin, professor of physics and astronomy at Barnard College. She is the author of "How the Universe Got Its Spots: Diary of a Finite Time in a Finite Space."

MR. GRIFFIN: I have no doubt that global -- that a trend of global warming exists. I am not sure that it is fair to say that it is a problem we must wrestle with. To assume that it is a problem is to assume that the state of earth's climate today is the optimal climate, the best climate that we could have or ever have had and that we need to take steps to make sure that it doesn't change. First of all, I don't think it's within the power of human beings to assure that the climate does...

...what if the equivalence principle (EP) is wrong? Galileo's experiments were only accurate to about 1 [per cent], leaving room for doubt, and skeptical physicists have been "testing EP" ever since. The best modern limits, based on, e.g., laser ranging of the Moon to measure how fast it falls around Earth, show that EP holds within a few parts in a trillion (1012). This is fantastically accurate, yet the possibility remains that the equivalence principle could fail at some more subtle level. "It's a possibility we must investigate," says physicist Clifford Will of Washington University in St. Louis, Missouri. "Discovering...

The new state is a solid filled with a collection of energy particles known as polaritons that have been trapped and slowed, explained lead investigator David Snoke, an associate professor in the physics and astronomy department in Pitt's School of Arts and Sciences. Snoke worked with Pitt graduate students Ryan Balili and Vincent Hartwell on the project. Using specially designed optical structures with nanometer-thick layers-which allow polaritons to move freely inside the solid-Snoke and his colleagues captured the polaritons in the form of a superfluid. In superfluids and in their solid counterparts, superconductors, matter consolidates to act as a single...

For a long time, Itzhak Bars has been studying time.. Einstein's theory of gravity and quantum theory don't fit together. Some piece is missing in the picture puzzle of physical reality. Bars thinks one of the missing pieces is a hidden dimension of time... With two times, Bars believes, many of the mysteries of today's laws of physics may disappear. Of course, it's not as simple as that. An extra dimension of time is not enough. You also need an additional dimension of space... Other dimensions could exist, however, if they were curled up in little balls, too tiny to...

...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...

IT HAS long been accepted, at least in theory, that other universes might exist and might even collide with ours. Yet the idea that we would ever be able to see the aftermath of such collisions, and so find evidence of other universes, has seemed beyond the scope of science. That is set to change. Anthony Aguirre of the University of California, Santa Cruz, thinks the proof of cosmic collisions could be all around us, as imprints in the cosmic microwave background (CMB) left over from the big bang. According to the standard model of cosmology, our universe underwent a...

String theory, simultaneously one of the most promising and controversial ideas in modern physics, may be more capable of helping probe the inner workings of subatomic particles than was previously thought... [T]he Princeton researchers have found new mathematical evidence that some of string theory's predictions mesh closely with those of a well-respected body of physics called "gauge theory," which has been demonstrated to underlie the interactions among quarks and gluons, the vanishingly small objects that combine to form protons, neutrons and other, more exotic subatomic particles. The discovery, say the physicists, could open up a host of uses for string...

Astronomers Deal Blow To Quantum Theories Of Time, Space, Gravity Huntsville - Mar 28, 2003 For the second time in as many months, images gathered by the Hubble Space Telescope (HST) are raising questions about the structures of time and gravity, and the fabric of space.Using two HST images, astronomers from Italy and Germany looked for but did not find evidence supporting a prevailing scientific theory that says time, space and gravity are composed of tiny quantum bits. Using existing theories, the team led by Dr. Roberto Ragazzoni from the Astrophysical Observatory of Arcetri, Italy, and the Max Planck Institute...

Roger Highfield describes a heroic mathematical enterprise that could lay bare the fundamentals of the cosmosMathematicians have successfully scaled their equivalent of Mount Everest. Today they unveil the answer to a problem that, if written out in tiny print, would cover an area the size of Manhattan. At the most basic level, the calculation is an arcane investigation of symmetry – in this case of an object that is 57 dimensional, rather than the usual three dimensional ones that we are familiar with. Although this object was first discovered in the 19th century. there is evidence that it could contain...

Tegmark has categorized four types of parallel universes: Level I universes include identical copies of our world physically separated from our observable universe by cosmic inflation... The Level II universes involve parallel worlds with different laws of physics existing on a landscape of possible vacuums, as has become popular in string theory. Level III parallel worlds are implied by taking the unitary mathematics of quantum theory seriously... The most extreme interpretation produces Level IV universes, where alternative mathematical structures produce universes with different laws of physics... Using the prediction of black holes coming from Einstein's General Theory of Relativity as...

The fact that he spent seven years as a patent clerk -- and wrote the paper for which he was awarded the Nobel Prize in that period -- is often presented as one of history's great injustices, but Einstein would disagree. He wrote in an autobiographical sketch that the daily examination of patent applications "stimulated me to see the physical ramifications of theoretical concepts." His superior, Friedrich Haller, "graciously ignored" the fact that Einstein completed his work in two or three hours and spent the rest of his time on physics; further, he insisted that the examiners "think that everything...

A giant cloud of superheated gas 6 million light years wide might be formed by the collective sigh of several supermassive black holes, scientists say. The plasma cloud, detailed in April 10 issue of Astrophysical Journal, might be the source of mysterious cosmic rays that permeate our universe. “One of the most exciting aspects of the discovery is the new questions it poses,” said study leader Philipp Kronberg of Los Alamos National Laboratories in New Mexico. “For example, what kind of mechanism could create a cloud of such enormous dimensions that does not coincide with any single galaxy or galaxy...

Quantum mechanics just got even stranger.There's only one way to describe the experiment performed by physicist Anton Zeilinger and his colleagues: it's unreal, dude. Measuring the quantum properties of pairs of light particles (photons) pumped out by a laser has convinced Zeilinger that "we have to give up the idea of realism to a far greater extent than most physicists believe today." By realism, he means the idea that objects have specific features and properties —that a ball is red, that a book contains the works of Shakespeare, or that an electron has a particular spin. For everyday objects, such...

Atlas holds key to scientists' map of Universe By Mark Henderson A vast cavern is the stage for tests to find the 'God particle' SCIENTISTS have taken a step closer to finding the “God particle” that is thought to shape the Universe. In a concrete cavern 130ft deep and bigger than the nave of Canterbury Cathedral, they will mimic the high-energy conditions that existed fractions of a second after the Big Bang to study a beam of energy a quarter of the thickness of a human hair. The vast Atlas cavern, which was completed last week at Cern, the European...

For decades, the big guns of American science have been the U.S. Department of Energy's particle colliders, which investigate the nature of matter by accelerating subatomic particles and smashing them together. Colliders at the Fermi National Accelerator Laboratory (Fermilab), Stanford Linear Accelerator Center (SLAC) and Brookhaven National Laboratory have discovered exotic particles such as the top quark and revealed phenomena that hint at new laws of physics. But this great American enterprise, like so many others, is now moving overseas. While the Europeans and Japanese build new particle accelerators, the U.S. is poised to shut down its premier colliders at...

A £2 billion project to answer some of the biggest mysteries of the universe has been delayed by months after scientists building it made basic errors in their mathematical calculations. The mistakes led to an explosion deep in the tunnel at the Cern particle accelerator complex near Geneva in Switzerland. It lifted a 20-ton magnet off its mountings, filling a tunnel with helium gas and forcing an evacuation. It means that 24 magnets located all around the 17-mile circular accelerator must now be stripped down and repaired or upgraded. The failure is a huge embarrassment for Fermilab, the American national...

From the masses and interactions of other particles that we know exist, physicists calculated that the Higgs is most likely to have a mass (or energy) of around 80 gigaelectronvolts (GeV). If particle accelerators smash particles together at that energy or higher, it should be possible to make one. This is what members of the Electroweak Working Group at CERN were doing for the 5 years until LEP (the Large Electron Positron Collider) closed down last year. Since then they've been sifting through the data they gathered--and found nothing. They rule out most possible masses for the Higgs, including the...

Super cool. Researchers have developed a technique to cool this dime-sized mirror (small circle suspended in the center of metal ring) to within one degree of absolute zero.Credit: Christopher Wipf/MITIf you want to really see quantum mechanics in action, you've got to turn the temperature down so low that even atoms stop moving. Physicists have come close to achieving this "absolute zero" state by using precision-tuned lasers, but the technique has only allowed researchers to freeze small groups of atoms at a time. Now members of an international team say they have managed to cool a dime-sized mirror to within...