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Surprisingly large matter/antimatter asymmetry discovered in Fermilab experimentsA large collaboration of physicists working at the Fermilab Tevatron particle collider has discovered evidence of an explanation for the prevalence of matter over antimatter in the universe. They found that colliding protons in their experiment produced short-lived B meson particles that almost immediately broke down into debris that included slightly more matter than antimatter. The two types of matter annihilate each other, so most of the material coming from these sorts of decays would disappear, leaving an excess of regular matter behind. This sort of matter/antimatter asymmetry accounts for the fact that...

Physicists from UCLA and Japan have discovered evidence of "natural nuclear accelerators" at work in our Milky Way galaxy, based on an analysis of data from the world's largest cosmic ray detector. The research is published Aug. 20 in the journal Physical Review Letters. Cosmic rays of the highest energies were believed by physicists to come from remote galaxies containing enormous black holes capable of consuming stars and accelerating protons at energies comparable to that of a bullet shot from a rifle. These protons — referred to individually as "cosmic rays" — travel through space and eventually enter our galaxy....

Initially hailed as a solution to the biggest question in computer science, the latest attempt to prove P ≠ NP – otherwise known as the "P vs NP" problem – seems to be running into trouble. Two prominent computer scientists have pointed out potentially "fatal flaws" in the draft proof by Vinay Deolalikar of Hewlett-Packard Labs in Palo Alto, California. Since the 100-page proof exploded onto the internet a week ago, mathematicians and computer scientists have been racing to make sense of it. The problem concerns the speed at which a computer can accomplish a task such as factorising a...

College Park, MD (August 10, 2010) -- Just as the path of photons of light can be directed by a mirror, atoms possessing a magnetic moment can be controlled using a magnetic mirror. Research reported in the Journal of Applied Physics investigates the feasibility of using magnetic domain walls to direct and ultimately trap individual atoms in a cloud of ultracold atoms. "We are looking for ways to build magnetic systems that can manipulate atoms," says author Thomas Hayward of the University of Sheffield in the United Kingdom. "By using soft ferromagnetic materials, in the form of nanostructures, we can...

In January, the true colour of the Universe was declared as somewhere between pale turquoise and aquamarine, by Ivan Baldry and Karl Glazebrook at John Hopkin's University in Baltimore Maryland. They determined the cosmic colour by combining light from over 200,000 galaxies within two billion light years of Earth. The data came from the Australian 2dF Galaxy Redshift Survey at the Anglo-Australian Observatory in New South Wales, Australia. The new colour is much more subdued Glazebrook now says the true colour this data gives is closer to beige. "I'm very embarrassed," he says, "I don't like being wrong." The ...

ON THE night of 30 June 2005, the sky high above La Palma in Spain's Canary Islands crackled with streaks of blue light too faint for humans to see. Atop the Roque de los Muchachos, the highest point of the island, though, a powerful magic eye was waiting and watching. MAGIC - the Major Atmospheric Gamma-ray Imaging Cherenkov Telescope - scans the sky each night for high-energy photons from the distant cosmos. Most nights, nothing remarkable comes. But every now and again, a brief flash of energetic light bears witness to the violent convulsions of a faraway galaxy. What MAGIC...

Physicists struggling to reconcile gravity with quantum mechanics have hailed a theory – inspired by pencil lead – that could make it all very simpleIT WAS a speech that changed the way we think of space and time. The year was 1908, and the German mathematician Hermann Minkowski had been trying to make sense of Albert Einstein's hot new idea - what we now know as special relativity - describing how things shrink as they move faster and time becomes distorted. "Henceforth space by itself and time by itself are doomed to fade into the mere shadows," Minkowski proclaimed, "and...

Inner space and outer space: Representing the bookends of atomic discovery, they are the two big attractions for the hundreds of visiting scientists who each year conduct research at ORNL's Holifield Radioactive Ion Beam Facility. Holifield's ability to create and analyze isotopes that exist for only seconds gives researchers a unique glimpse into the inner workings of atomic nuclei, as well as how they interact with each other and with high-energy particles. Understanding these processes provides astrophysicists with insights they will need to continue to unravel the mystery of how the same processes could have created of all of the...

The apparent development of a large void of some billion light-years in diameter in the Constellation Eridanus appears to be improbable given current cosmological models. A radical and controversial theory proposes that it is a "universe-in-mass black hole" rather than hypothetical dark matter responsible for the phenomenon described as the expanding-accelerating universe. This radical theory of cosmology suggests that stars at the edge of the Hubble length universe are being consumed by a universe-in-mass black hole. In August of 2007, astronomers at the University of Minnesota located a gigantic hole in the universe. This empty space, stretching nearly a billion...

Look past the details of a wonky discovery by a group of California scientists -- that a quantum state is now observable with the human eye -- and consider its implications: Time travel may be feasible. Doc Brown would be proud. The strange discovery by quantum physicists at the University of California Santa Barbara means that an object you can see in front of you may exist simultaneously in a parallel universe -- a multi-state condition that has scientists theorizing that traveling through time may be much more than just the plaything of science fiction writers.

An international team of scientists led by groups from the Max Planck Institute of Quantum Optics (MPQ) in Garching, Germany, and from the U.S. Department of Energy’s Lawrence Berkeley National Laboratory and the University of California at Berkeley has used ultrashort flashes of laser light to directly observe the movement of an atom’s outer electrons for the first time. Through a process called attosecond absorption spectroscopy, researchers were able to time the oscillations between simultaneously produced quantum states of valence electrons with great precision. These oscillations drive electron motion. “With a simple system of krypton atoms, we demonstrated, for the...

"Quantum entanglement" may sound like an awful sci-fi romance flick, but it's actually a phenomenon that physicists say may someday lead to the ability to teleport an object all the way across the galaxy instantly. It's not exactly the Star Trek version of teleportation, where an object disappears then reappears somewhere else. Rather, it "entangles" two different atoms so that one atom inherits the properties of another. "According to the quantum theory, everything vibrates," theoretical physicist Michio Kaku tells NPR's Guy Raz. Kaku is a frequent guest on the Science and Discovery channels. "When two electrons are placed close together,...

All of the matter in the universe—everything we see, feel and smell—has a certain predictable structure, thanks to the tiny electrons spinning around their atomic nuclei in a series of concentric shells or atomic levels. A fundamental tenet of this orderly structure is that no two electrons can occupy the same atomic level (quantum state) at the same time—a principle called the Pauli exclusion principle, which is based on Albert Einstein’s theory of relativity and quantum theory. However, a team of Syracuse University physicists recently developed a new theoretical model to explain how the Pauli exclusion principle can be violated...

When scientists send their spacecraft across the universe, they save fuel by performing “slingshot fly-bys”. This is where, rather than firing up the thrusters, the craft changes its trajectory by harnessing the enormous gravitational pull of a planet. However, this trick has had an unexpected side-effect: it seems to produce a change in speed that no one, since it was first discovered in the early 1990's, can account for. Experts are intrigued by the fact that while the acceleration is tiny and has no significant effect on NASA missions, it holds great interest because no explanation based on conventional physics...

Graphene, the extraordinary form of carbon that consists of a single layer of carbon atoms, has produced another in a long list of experimental surprises. In the current issue of the journal Science, a multi-institutional team of researchers headed by Michael Crommie, a faculty senior scientist in the Materials Sciences Division at the U.S. Department of Energy’s Lawrence Berkeley National Laboratory and a professor of physics at the University of California at Berkeley, reports the creation of pseudo-magnetic fields far stronger than the strongest magnetic fields ever sustained in a laboratory – just by putting the right kind of strain...

Study of quantum phase changes reveals surprising relationship between magnetism and electricityU.S., German and Austrian physicists studying the perplexing class of materials that includes high-temperature superconductors are reporting this week the unexpected discovery of a simple "scaling" behavior in the electronic excitations measured in a related material. The experiments, which were conducted on magnetic heavy-fermion metals, offer direct evidence of the large-scale electronic consequences of "quantum critical" effects. The experimental and theoretical results are reported this week in the Proceedings of the National Academy of Science by physicists at Rice University in Houston; the Max Planck Institute for Chemical Physics...

WE COULD be living inside a black hole. This head-spinning idea is one cosmologist's conclusion based on a modification of Einstein's equations of general relativity that changes our picture of what happens at the core of a black hole. In an analysis of the motion of particles entering a black hole, published in March, Nikodem Poplawski of Indiana University in Bloomington showed that inside each black hole there could exist another universe (Physics Letters B, DOI: 10.1016/j.physletb.2010.03.029). "Maybe the huge black holes at the centre of the Milky Way and other galaxies are bridges to different universes," Poplawski says. If...

College Park, MD (July 27, 2010) -- Earth's climate is strongly influenced by the presence of particles of different shapes and origins -- in the form of dust, ice and pollutants -- that find their way into the lowest portion of the atmosphere, the troposphere. There, water adsorbed on the surface of these particles can freeze at higher temperatures than pure water droplets, triggering rain and snow. Researchers at Spain's Centre d'Investigació en Nanociència i Nanotecnologia (CIN2) have studied the underlying mechanisms of water condensation in the troposphere and found a way to make artificial materials to control water condensation...

(PhysOrg.com) -- A team of scientists at MIT have discovered a previously unknown phenomenon that can cause powerful waves of energy to shoot through minuscule wires known as carbon nanotubes. The discovery could lead to a new way of producing electricity, the researchers say.The phenomenon, described as thermopower waves, “opens up a new area of energy research, which is rare,” says Michael Strano, MIT’s Charles and Hilda Roddey Associate Professor of Chemical Engineering, who was the senior author of a paper describing the new findings that appeared in Nature Materials on March 7. The lead author was Wonjoon Choi, a...

When American space pioneer, Dr Robert L Forward, proposed in 1984 a way of greatly improving satellite telecommunications using a new family of orbits, some claimed it was impossible. But now engineers at the University of Strathclyde's Advanced Space Concepts Laboratory have proved that Forward was right. The late Dr Forward - a renowned physicist who worked in the United States and from his second home in Scotland - believed it was possible to use 'displaced orbits' to deploy more satellites to the north or south of the Earth's equator, helping to meet the growing demand for communications. He proposed...