Keyword: stringtheory
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Fabrication schematic of ordered mesoporous fewlayer carbon (OMFLC). Credit: Science (2015). DOI: 10.1126/science.aab3798 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ (Phys.org) - A team of researchers working in China has found a way to dramatically improve the energy storage capacity of supercapacitors - by doping carbon tubes with nitrogen. In their paper published in the journal Science, the team describes their process and how well the newly developed supercapacitors worked, and their goal of one day helping supercapacitors compete with batteries. Like a battery, a capacitor is able to hold a charge, unlike a battery, however, it is able to be charged and discharged very quickly...
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There are a lot of different ways to define science, but perhaps one that everyone can agree on is that it’s a process by which: 1.knowledge about the natural world or a particular phenomenon is gathered, 2.a testable hypothesis is put forth concerning a natural, physical explanation for that phenomenon, 3.that hypothesis is then tested and either validated or falsified, 4.and an overarching framework — or scientific theory — is constructed to explain the hypothesis and that makes predictions about other phenomena, 5.which is then tested further, and either validated, in which case new phenomena to test are sought (back...
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Black holes earn their name because their gravity is so strong not even light can escape from them. Oddly, though, physicists have come up with a bit of theoretical sleight of hand to retrieve a speck of information that's been dropped into a black hole. The calculation touches on one of the biggest mysteries in physics: how all of the information trapped in a black hole leaks out as the black hole "evaporates." Many theorists think that must happen, but they don't know how. Unfortunately for them, the new scheme may do more to underscore the difficulty of the larger...
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Imperial College London has found that two networks of genes determine whether people are intelligent or not so bright. Genes which make people intelligent have been discovered and scientists believe they could be manipulated to boost brain power. Researchers have believed for some time that intellect is inherited with studies suggesting that up to 75 per cent of IQ is genetic, and the rest down to environmental factors such as schooling and friendship groups. But until now, nobody has been able to pin-point exactly which genes are responsible for better memory, attention, processing speed or reasoning skills. Now Imperial College...
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Black holes can only grow if they have a gas disc to feed on NASA Goddard Space Flight Center/Flickr ======================================================================================================== Black holes can only grow to 50 billion times the mass of the Sun, before they lose their only source of 'food' and stop growing. Scientists discovered that black holes have a size limit, as when it gets so big, the gas which feeds the great void loses its energy, and falls into the unknown. A researcher from the University of Leicester analysed the disc of gas which surrounds supermassive black holes at the centre of galaxies. He found that...
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The Universe we know and love — with Einstein’s General Relativity as our theory of gravity and quantum field theories of the other three forces — has a problem that we don’t often talk about: it’s incomplete, and we know it. Einstein’s theory on its own is just fine, describing how matter-and-energy relate to the curvature of space-and-time. Quantum field theories on their own are fine as well, describing how particles interact and experience forces. Normally, the quantum field theory calculations are done in flat space, where spacetime isn’t curved. We can do them in the curved space described by...
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A Fight for the Soul of Science String theory, the multiverse and other ideas of modern physics are potentially untestable. At a historic meeting in Munich, scientists and philosophers asked: should we trust them anyway? Laetitia Vancon for Quanta MagazinePhysicists George Ellis (center) and Joe Silk (right) at Ludwig Maximilian University in Munich on Dec. 7. By: Natalie WolchoverDecember 16, 2015 Comments (17) Share this: facebooktwitterredditmail PDF Print Physicists typically think they “need philosophers and historians of science like birds need ornithologists,†the Nobel laureate David Gross told a roomful of philosophers, historians and physicists last week in Munich, Germany,...
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TORONTO — Dark matter inspires many strange theories, but until now few have involved giant lizards and the origins of humanity. If physicist Lisa Randall’s theory is correct, however, there is a clear link between dark matter, the great unknown majority of universal stuff and the extinction of the dinosaurs, which cleared the path for the rise of mammals, including that special species, homo sapiens. Roughly, her idea is that the rotation of a vast disc of dark matter through our solar system dislodged an asteroid from a weak and distant orbit, and sent it hurtling toward Earth, where it...
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Scientists in Germany said Thursday they had reached a milestone in a quest to derive energy from nuclear fusion, billed as a potentially limitless, safe and cheap source. [...] After spending a billion euros and nine years' construction work, physicists working on a German project called the "stellarator" said they had briefly generated a superheated helium plasma inside a vessel -- a key point in the experimental process. [...] The German experiment, using a machine called Wendelstein 7-X, was aimed at seeing whether it was possible to heat helium atoms with a microwave laser and to briefly contain the plasma...
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Even gluttons can't eat forever. When black holes at the hearts of galaxies swell to 50 billion times the mass of our sun, they may lose the discs of gas they use as cosmic feedlots. Most galaxies host a supermassive black hole at their centre. Around this is a region of space where gas settles into an orbiting disc. The gas can lose energy and fall inwards, feeding the black hole. But these discs are known to be unstable and prone to crumbling into stars. Theoretically, a black hole could grow so big that it swallows up the stable part...
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[This article is much more interesting than its headline] Several years ago it was discovered that the early Solar system contained a significant amount of plutonium-244. Considering its short-lived cycle, plutonium-244 that existed over four billion years ago when Earth formed has long since decayed but its daughter elements have been detected. Plutonium is a radioactive element. Its longest-lived isotope is plutonium-244 with a lifetime of 120 million years. Detection of plutonium-244 in nature would imply that the element was synthesized in astrophysical phenomena not so long ago (at least in Galactic time scales) and hence its origin cannot be...
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Rice University scientists are making small, flexible microsupercapacitors in a room-temperature process they claim shows promise for manufacturing in bulk. The technique is based on their method to burn patterns of spongy graphene into plastic sheets with a commercial laser. Credit: Tour Group/Rice University ====================================================================================================================================== Rice University researchers who pioneered the development of laser-induced graphene have configured their discovery into flexible, solid-state microsupercapacitors that rival the best available for energy storage and delivery. The devices developed in the lab of Rice chemist James Tour are geared toward electronics and apparel. They are the subject of a new paper in the...
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American space agency, the NASA had recently observed flares of X-rays from a black hole, which goes against the conventional notion that they are compact particles with such huge gravity that even light can't escape. Last month NASA announced that two of its space telescopes caught a huge burst of X-ray spewing out of a super massive black hole. These flairs appeared to be be triggered by the eruption of a charged particle from the black hole, which according to conventional belief doesn't let anything out. The latest findings are in accordance with the theory of Indian astrophysicist Abhas Mitra...
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These tungsten ditelluride crystals behave as insulators for current applied in some directions and as conductors for current applied in other directions. The researchers found that this behavior is due to a newly theorized particle, the type-II Weyl fermion. Credit: Wudi Wang and N. Phuan Ong, Princeton University --------------------------------------------------------------------------------------------------------------------------------------- An international team of researchers has predicted the existence of a new type of particle called the type-II Weyl fermion in metallic materials. When subjected to a magnetic field, the materials containing the particle act as insulators for current applied in some directions and as conductors for current applied in other...
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Gary Prezeau of NASA’s Jet Propulsion Laboratory in Pasadena, Calif., describes the results of his theoretical model that goes some way to explain how streams of dark matter particles may interact with our planet's gravitational field. "A (dark matter) stream can be much larger than the solar system itself, and there are many different streams crisscrossing our galactic neighborhood," said Prézeau in a JPL press release. "When gravity interacts with the cold dark matter gas during galaxy formation, all particles within a stream continue traveling at the same velocity." As these streams begin to interact with a planet, according to...
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Physics is built out of philosophically fascinating ideas. Or, at least, ideas that fascinate us as physicists. We are often moved to reverentially proclaim the beauty of various concepts and theories. Sometimes this beauty makes sense to other people (we're made of star stuff) and other times it's opaque (Frobenius manifolds in psuedo-Euclidean spaces). I have my own personal favorite idea. It arises from the philosophically fantastic (but mathematically moderate) workings of Einstein's relativity theory. The theory of special relativity holds that time and space are not separate entities, each operating on its own; rather they are intimately and inextricably...
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Researchers have written quantum code on a silicon chip for the first time And so it begins... FIONA MACDONALD 17 NOV 2015 For the first time, Australian engineers have demonstrated that they can write and manipulate the quantum version of computer code on a silicon microchip. This was done by entangling two quantum bits with the highest accuracy ever recorded, and it means that we can now start to program for the super-powerful quantum computers of the future.Engineers code regular computers using traditional bits, which can be in one of two states: 1 or 0. Together, two bits...
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Credit: NASA, ESA, S. Baum & C. O’Dea (RIT), R. Perley & W. Cotton (NRAO/AUI/NSF), and the Hubble Heritage Team (STScI/AURA) =============================================================================================================== Scientists often use the combined power of multiple telescopes to reveal the secrets of the Universe – and this image is a prime example of when this technique is strikingly effective. The yellow-hued object at the centre of the frame is an elliptical galaxy known as Hercules A, seen by the Earth-orbiting NASA/ESA Hubble Space Telescope. In normal light, an observer would only see this object floating in the inky blackness of space. However, view Hercules A with...
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Lasers could heat materials to temperatures hotter than the centre of the Sun in only 20 quadrillionths of a second, according to new research. Theoretical physicists from Imperial College London have devised an extremely rapid heating mechanism that they believe could heat certain materials to ten million degrees in much less than a million millionth of a second. The method, proposed here for the first time, could be relevant to new avenues of research in thermonuclear fusion energy, where scientists are seeking to replicate the Sun’s ability to produce clean energy. The heating would be about 100 times faster than...
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Image: J021659-044920. The red and yellow lobes are the galaxy’s radio lobes. The red spot in the center is the visible galaxy. Prathamesh Tamhane/Yogesh Wadadekar. ================================================================================================================== Astronomers in India have discovered a very unusual galaxy, and it’s dying. By now, in fact, it’s probably already dead. The new galaxy, known as J021659-044920, is 9 billion light years away from Earth. That means it’s really old in cosmic terms (but not quite as old as the oldest object astronomers have ever found, a galaxy 13 billion light years away called UDFy-38135539). Viewed in the visible spectrum, J021659-044920spans about 100,000 light years...
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