Free Republic

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...

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...

GENEVA - A 43-foot-long magnet for the world's largest particle collider broke "with a loud bang and a cloud of dust" during a high-pressure test, and officials said Tuesday they are working to find a replacement part. The part that failed March 27 was in a super-cooled magnet designed to focus streams of protons so that they collide and allow scientists to study the results of the collision, giving them a better understanding of the makeup of matter, according to Fermilab, based in suburban Chicago, which has an accelerator of its own and is helping build one deep beneath the...

Michael Turner... the University of Chicago cosmologist had the unenviable task of trying to crown a winner in a match-up between Brian Greene and Lawrence Krauss, two physics heavyweights duking it out over the merits -- or lack thereof -- of the so-called Theory of Everything... Last night's debate did little to settle the argument, but a packed house of academics, physics geeks, and just-curious laypeople seemed to enjoy themselves nonetheless. Krauss threw the first punch. A professor at Case Western Reserve University in Cleveland, Ohio, and an expert on black holes, dark matter, and dark energy, Krauss said he...

The speed of gravity has been measured for the first time. The landmark experiment shows that it travels at the speed of light, meaning that Einstein's general theory of relativity has passed another test with flying colours. Ed Fomalont of the National Radio Astronomy Observatory in Charlottesville, Virginia, and Sergei Kopeikin of the University of Missouri in Columbia made the measurement, with the help of the planet Jupiter. "We became the first two people to know the speed of gravity, one of the fundamental constants of nature," the scientists say, in an article in New Scientist print edition. One important...

The structure is described in the form of a vast matrix An international team of mathematicians has detailed a vast complex numerical "structure" which was invented more than a century ago.Mapping the 248-dimensional structure, called E8, took four years of work and produced more data than the Human Genome Project, researchers said. E8 is a "Lie group", a means of describing symmetrical objects. The team said their findings may assist fields of physics which use more than four dimensions, such as string theory. Lie groups were invented by the 19th Century Norwegian mathematician Sophus Lie (pronounced "Lee"). It's as...

An international team of 18 mathematicians, including two from MIT, has mapped one of the largest and most complicated structures in mathematics. If written out on paper, the calculation describing this structure, known as E8, would cover an area the size of Manhattan... MIT's David Vogan, a professor in the Department of Mathematics and member of the research team, will present the work today, Monday, March 19 at 2 p.m. in Room 1-190. His talk, "The Character Table for E8, or How We Wrote Down a 453,060 x 453,060 Matrix and Found Happiness," is open to the public. E8, (pronounced...

RIVERSIDE, Calif. -- April 2, 2003 -- In a discovery that is likely to impact fields as diverse as atomic physics, chemistry and nanotechnology, researchers have identified a new physical phenomenon, electrostatic rotation, that, in the absence of friction, leads to spin. Because the electric force is one of the fundamental forces of nature, this leap forward in understanding may help reveal how the smallest building blocks in nature react to form solids, liquids and gases that constitute the material world around us. Scientists Anders Wistrom and Armik Khachatourian of University of California, Riverside first observed the electrostatic rotation in...

Albert Einstein might be astonished to learn that NASA physicists have applied his relativity theory to a concept he introduced but later disliked namely that two particles that interact could maintain a connection even if separated by a vast distance. Researchers often refer to this connection as "entanglement." Researchers at NASA's Jet Propulsion Laboratory, Pasadena, Calif., have discovered that this entanglement is relative, depending on how fast an observer moves with respect to the particles, and that entanglement can be created or destroyed just by relative motion. This might change the way entanglement is used on future spacecraft that move...