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Explanation: What are black hole jets made of? Many black holes in stellar systems are surely surrounded by disks of gas and plasma gravitationally pulled from a close binary star companion. Some of this material, after approaching the black hole, ends up being expelled from the star system in powerful jets emanating from the poles of the spinning black hole. Recent evidence indicates that these jets are composed not only electrons and protons, but also the nuclei of heavy elements such as iron and nickel. The discovery was made in system 4U1630-47 using CSIRO’s Compact Array of radio telescopes in...

Scientists at the Homestake Gold Mine in South Dakota running the biggest, most sensitive dark matter detector yet released its first round of results yesterday -- and they found nothing. The Large Underground Xenon dark matter experiment, or LUX, consists of a vat of 368 kilograms of liquid xenon to minus 110 degrees Celsius, surrounded by a tank of water. LUX sits 4,850 feet underground at the old mine, shielded from cosmic rays. An international team of researchers watched for three months to see if any WIMPS -- weakly interacting massive particles -- would pass through the rock and reveal...

Astronomers from York University in Canada have identified an undocumented type of quasar where gas appears to be getting sucked into a black hole. This may not sound surprising, but current theories say that isn't supposed to happen. Quasars are hyperactive and extremely bright discs of hot gas that surround supermassive black holes. They're also known as galactic nucleuses. The Milky Way has one at its center. All the junk that's rapidly spinning down the drain hole forms a compact disc with a radius that's larger than Earth's orbit around the Sun and a temperature that's hotter than the surface...

Using inexpensive materials configured and tuned to capture microwave signals, researchers at Duke University's Pratt School of Engineering have designed a power-harvesting device with efficiency similar to that of modern solar panels. The device wirelessly converts the microwave signal to direct current voltage capable of recharging a cell phone battery or other small electronic device, according to a report appearing in the journal Applied Physics Letters in December 2013. (It is now available online.) It operates on a similar principle to solar panels, which convert light energy into electrical current. But this versatile energy harvester could be tuned to harvest...

"It is widely accepted now that, without a doubt, information is physical and quantum physics provides the rules of that physical behavior," George Mason University computer science professor Richard Gomez told NewsFactor. Alan Turing might be considered the "John Forbes Nash of computer science" -- a troubled young Princeton genius who achieved prominence in the 1950s. Turing published one of the top 10 papers in all of 20th-century science -- "On the Computability of Numbers." He killed himself over a conviction for homosexuality at the height of his genius, but since his death, his definition of "computability" has stood untouched...

Okay, but what exactly is a gravitational wave and how could they help us crack the conundrum of the black hole code? A gravitational wave is akin to a ripple in space-time. Albert Einstein predicted that massive bodies changing speed or direction generate these gravitational waves. Picture bodies like a pair of black holes orbiting each other. This then creates a gravitational wave that ripples outwards, like a disturbance in a still pool of water after a leaf has dropped onto its surface and ripples are sent across the surface. Like star-crossed lovers, the black holes of two merging galaxies...

To understand the coronal heating problem, imagine a flame coming out of an ice cube. A similar effect occurs on the surface of the Sun. Nuclear fusion in the center of the Sun heats the solar core to 15 million degrees. Moving away from this furnace, by the time one arrives at the surface of the Sun, the gas has cooled to a relatively refreshing 10,800° Fahrenheit (6,000° Celsius). But the temperature of the gas in the corona, above the solar surface, soars back up to over 1.8 million degrees F (1 million degrees C). What causes this unexpected temperature...

The strongest material ever could be carbyne, atom-thick chains of carbon, according to theoretical calculations by Rice University Physicists. The big question is now if and when anyone can make it in bulk. Carbyne is a chain of carbon atoms held together by either double or alternating single and triple atomic bonds. That makes it a true one-dimensional material, unlike atom-thin sheets of graphene, which have a top and a bottom, or hollow nanotubes, which have an inside and outside. These carbyne nanorods or nanoropes, if they can be made, would have a host of remarkable and useful properties, as...

Wikimedia Commons, ULBPhysics laureates. Peter Higgs (left) and François Englert. The most eagerly anticipated and potentially controversial Nobel Prize for physics in many years was awarded today—following a nail-biting hourlong delay—exactly according to the expected script: The winners are Peter Higgs and his fellow theorist François Englert for, essentially, predicting the Higgs boson. The winners were much heralded following last year’s discovery of the Higgs by physicists at the CERN particle physics lab near Geneva, Switzerland, using its Large Hadron Collider (LHC).That finding put in place the last piece of the puzzle to complete the standard model of fundamental particles...

Explanation: It is still not known why the Sun's light is missing some colors. Here are all the visible colors of the Sun, produced by passing the Sun's light through a prism-like device. The spectrum was created at the McMath-Pierce Solar Observatory and shows, first off, that although our white-appearing Sun emits light of nearly every color, it does indeed appear brightest in yellow-green light. The dark patches in the above spectrum arise from gas at or above the Sun's surface absorbing sunlight emitted below. Since different types of gas absorb different colors of light, it is possible to determine...

The cosmic microwave background sky, here mapped by NASA's Wilkinson Microwave Anisotropy Probe, has a polarization, represented by white bars. Future experiments might measure the polarization with enough sensitivity to prove the existence of gravitons, the quanta of gravity. Can a quantum of gravity ever be detected? Two physicists suggest that it can — using the entire Universe as a detector. Researchers think that the gravitational force is transmitted by an elementary particle called the graviton, just as the electromagnetic force is carried by photons. But most of them despair about ever recording individual gravitons. That is because gravity is...

A new advance in accelerator technology has scientists creating tiny glass chips smaller than a grain of rice that can power electrons up to speeds 10 times faster than present-day conventional technology. Experts from Stanford University and U.S. Department of Energy's (DOE) SLAC National Accelerator detailed their glass chip accelerator research in a study in the journal Nature. The researchers reveal that they are able to achieve such incredible acceleration in such small distances by using commercial lasers to speed up the electrons instead of microwaves, which are typically used. These new chips offer an unprecedented level of acceleration, clocking...

Goodbye Big Bang, hello black hole? A new theory of the universe's creation Enlarge Artist’s conception of the event horizon of a black hole. Credit: Victor de Schwanberg/Science Photo Library Could the famed "Big Bang" theory need a revision? A group of theoretical physicists suppose the birth of the universe could have happened after a four-dimensional star collapsed into a black hole and ejected debris. Before getting into their findings, let's just preface this by saying nobody knows anything for sure. Humans obviously weren't around at the time the universe began. The standard theory is that the universe grew from...

A Jewel at the Heart of Quantum Physics Artist’s rendering of the amplituhedron, a newly discovered mathematical object resembling a multifaceted jewel in higher dimensions. Encoded in its volume are the most basic features of reality that can be calculated — the probabilities of outcomes of particle interactions. Physicists have discovered a jewel-like geometric object that dramatically simplifies calculations of particle interactions and challenges the notion that space and time are fundamental components of reality.“This is completely new and very much simpler than anything that has been done before,” said Andrew Hodges, a mathematical physicist at Oxford University who has...

Two groups of astronomers have used data from ESO telescopes to make the best three-dimensional map yet of the central parts of the Milky Way. They have found that the inner regions take on a peanut-like, or X-shaped, appearance from some angles. This odd shape was mapped by using public data from ESO’s VISTA survey telescope along with measurements of the motions of hundreds of very faint stars in the central bulge. One of the most important and massive parts of the galaxy is the galactic bulge. This huge central cloud of about 10,000 million stars spans thousands of light-years,...

Astronomers using NASA's Hubble Space Telescope have solved a 40-year mystery on the origin of the Magellanic Stream, a long ribbon of gas stretching nearly halfway around our Milky Way galaxy. The Large and Small Magellanic Clouds, two dwarf galaxies orbiting the Milky Way, are at the head of the gaseous stream. Since the stream's discovery by radio telescopes in the early 1970s, astronomers have wondered whether the gas comes from one or both of the satellite galaxies. New Hubble observations reveal most of the gas was stripped from the Small Magellanic Cloud about two billion years ago, and a...

The universe may end in another 10 billion years or sooner if the heaviest of all the known elementary particles, the top quark, is even heavier than previously thought, researchers say. If the top quark is not heavier than experiments currently suggest, then an even stranger fate may await the cosmos: disembodied brains and virtually anything else could one day randomly materialize into existence. The protons and neutrons that make up the nuclei of atoms are made of elementary particles known as quarks. Protons and neutrons are made up of the lightest and most stable flavors of quark: the up...

Nobody knows how the universe’s biggest black holes grow so large. Now one astrophysicist says it’s because they feed on the quantum foam that makes up the fabric of spacetime One of the more fascinating astrophysical discoveries in recent years is that almost all galaxies hide supermassive black holes at their cores. Indeed, astronomers believe that galaxies and black holes have a kind of symbiotic relationship so that one cannot form or grow without the other. The evidence comes from observations of galaxies both near and far—almost all contain huge black holes. But that raises an interesting question. We see...

A new approach to the unification of general theory of relativity and quantum theory Present-day physics cannot describe what happened in the Big Bang. Quantum theory and the theory of relativity fail in this almost infinitely dense and hot primal state of the universe. Only an all-encompassing theory of quantum gravity which unifies these two fundamental pillars of physics could provide an insight into how the universe began. Scientists from the Max Planck Institute for Gravitational Physics (Albert Einstein Institute) in Golm/Potsdam and the Perimeter Institute in Canada have made an important discovery along this route. According to their theory,...

ANN ARBOR—Moonless nights outside the Cerro Tololo astronomical observatory in Chile are so dark that when you look down, you can't see your feet. "You can't see your hands," said David Gerdes, physics professor at the University of Michigan. "But you can hold them up to the sky and see a hand-shaped hole with no stars in it. It's really incredible." From this site in the Andes over the next five years, an international team will map one-eighth of the sky in unprecedented detail—aiming to make a time lapse of the past 8 billion years of a slice of the...