Keyword: stringtheory
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'As if millions of voices suddenly cried out in terror and were suddenly silenced' A pair of European astrophysicists believe they've solved the mystery of exceedingly bright, never-repeated flashes of radio waves that come to us from the distant past. The source of those brief, intense flashes can be defined in two ways, depending upon whether you'd prefer to look at the event as a death or a birth. "We suggest that a fast radio burst represents the final signal of a supramassive rotating neutron star that collapses to a black hole due to magnetic braking," write Heino Falcke of...
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It’s a recurring theme in astronomy: observers see a blast of energy out in the cosmos, scratch their heads in confusion for a while, and finally uncover the existence of something entirely surprising and new. It happened with the quasars (now known to be gigantic burps from black holes swallowing hot gas), the pulsars (fast-spinning neutron stars sending out blips of radio noise hundreds of times every second), and even the Big Bang itself, first seen as a stream of microwaves slamming into Earth from all directions, nearly 14 billion years after the event itself.Now it may be happening again....
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Just as sailors once used the stars to navigate the sea, space travelers may be able to use the stars to navigate the solar system. Except that this time, the stars we’d use will be dead ones. A specific class of neutron stars known as pulsars, defined by the repeated pulses of radiation they emit. The trick, according to a recent paper, may be to use pulsars as a form of interplanetary – and possibly even interstellar – GPS. Theories and ideas on spacecraft engines are plentiful. Foundations such as Icarus Interstellar keenly advocate the development of new propulsion systems,...
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Last week, in Nice, France, I was privileged to participate, along with 30 scholars, mostly scientists and mathematicians, in a conference on the question of whether the universe was designed, or at least fine-tuned, to make life, especially intelligent life. Participants — from Yale, Princeton, Harvard, Berkeley and Columbia among other American and European universities — included believers in G0D, agonistics and atheists.
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Title:NASA Finds Black Hole Cluster No matter how old you are, space never stops being cool. That applies doubly to black holes, which is why NASA's latest discovery should be considered totally awesome: using the Chandra X-ray observatory, the agency found an "unprecedented" cluster of black holes in the Andromeda galaxy. How unprecedented? There could be 26 of them in this cluster alone. And these were just the ones that were immediately identifiable, as scientists say there are likely many more that are currently invisible. Said the lead author of the study, "We think it's just the tip of the...
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One physicist says he likes this theory because of “its simplicity, uniqueness and the fact that it can be tested.”Theoretical physicists at Vanderbilt University contend that a simply theory may explain mysterious dark matter. They propose that most of the matter in the universe may be constructed of particles that have an abnormal, donut-shaped electromagnetic field known as an anapole. According to a news release from Vanderbilt University, Professor Robert Scherrer and post-doctoral fellow Chiu Man Ho carried out an in-depth analysis to determine the validity of this theory. Scherrer points out that he likes this theory because of “its...
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'Superatoms' can be used to make ionic-esque lattices using C60 (black) and metal chalcogenides © Science/AAASCould a new periodic table be on the horizon, populated not by conventional elements but by new ‘superatoms’ designed in the lab? This is the intriguing implication of new work by US chemists, who have made structural analogues of simple ionic compounds such as sodium chloride and cadmium iodide by interacting large molecular clusters instead of individual atoms.The new compounds have unexpected electronic and magnetic properties, opening the prospect for the design of bespoke solid state materials whose properties can be tuned by the...
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New Science of Cosmography Reveals 3-D Map of the Local Universe The three-dimensional structure of the local universe may one day become as familiar as our local geography thanks to a new generation of maps that reveal our neighbourhood’s rich complexity and our place within it The geography of our world is one of the great cultural invariants. There can hardly be the person on the planet who isn’t familiar with the shape of the continents and how they dovetail together or of the Earth is a pale blue sphere orbiting the Sun with seven other planets.Given a three-dimensional model...
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The spectacular discovery of the Higgs boson in July 2012 confirmed a nearly 50-year-old theory of how elementary particles acquire mass, which enables them to form big structures such as galaxies and humans. “The fact that it was seen more or less where we expected to find it is a triumph for experiment, it’s a triumph for theory, and it’s an indication that physics works,” Arkani-Hamed told the crowd. However, in order for the Higgs boson to make sense with the mass (or equivalent energy) it was determined to have, the LHC needed to find a swarm of other particles,...
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A pocket-sized device which can harness fusion, the energy source of the Sun, with the help of crystals no bigger than a sugar cube has been developed by scientists. The "pocket fusion" device, described today in the journal Nature, raises new possibilities in fields as diverse as space propulsion, medical diagnostics, cancer treatment and the hunt for concealed weapons. Now Brian Naranjo, Jim Gimzewski, a professor from Glasgow, and Prof Seth Putterman of the University of California, Los Angeles describe a breathtakingly simple way to fuse atoms with the help of a crystal. They fused atoms of deuterium - heavy...
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Sonoluminescence : How Bubbles Turn Sound into Light
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From the idea that our universe is one among many, to the revelation that mathematician Pythagoras didn't actually invent the Pythagorean theorem, here are eight shocking things we learned from reading physicist Stephen Hawking's new book, "The Grand Design," written with fellow physicist Leonard Mlodinow of Caltech. The book, covering major questions about the nature and origin of the universe, was released Sept. 7, 2010, by its publisher, Bantam.
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Enlarge Left panel: Air molecules whiz around at a variety of speeds, and some are very fast. When they collide with both heavy and light elements - for example, xenon (purple) and silicon (orange) - these fast moving particles have enough momentum to affect both nuclei. Right panel: Dark matter particles are moving more slowly and are less able to affect the heavy xenon nucleus. As a result, detectors made from lighter materials like silicon may prove to be more effective at picking up signals of dark matter. Credit: Greg Stewart/SLAC National Accelerator Laboratory (Phys.org) —Now that it looks...
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Credit: Phys. Rev. Lett. 110, 211302 (2013) (Phys.org) —A team of Harvard University physicists has proposed the possible existence of a type of dark matter not described by current physics models. In their paper published in the journal Physical Review Letters, the team suggests it's possible that not all dark matter is cold and collision-less. In the visible universe, galaxies form into a disk shape—the Milky Way is a good example. All of its members align roughly along a single plane, this due to the forces of gravity and spin. Objects form into masses which, over time, spread out...
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Diophantus of Alexandria -------------------------------------------------------------------------------- Born: about 200 Died: about 284 Previous (Chronologically) Next Biographies Index Previous (Alphabetically) Next Main index -------------------------------------------------------------------------------- Diophantus, often known as the 'father of algebra', is best known for his Arithmetica, a work on the solution of algebraic equations and on the theory of numbers. However, essentially nothing is known of his life and there has been much debate regarding the date at which he lived. There are a few limits which can be put on the dates of Diophantus's life. On the one hand Diophantus quotes the definition of a polygonal number from the work...
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Every pure mathematician has experienced that awkward moment when asked, “So what’s your research good for?” There are standard responses: a proud “Nothing!”; an explanation that mathematical research is an art form like, say, Olympic gymnastics (with a much smaller audience); or a stammered response that so much of pure math has ended up finding application that maybe, perhaps, someday, it will turn out to be useful. That last possibility is now proving itself to be dramatically true in the case of category theory, perhaps the most abstract area in all of mathematics. Where math is an abstraction of the...
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Astronomers have found a galaxy turning gas into stars with almost 100 percent efficiency, a rare phase of galaxy evolution that is the most extreme yet observed. The findings come from the IRAM Plateau de Bure interferometer in the French Alps, NASA's Wide-field Infrared Survey Explorer and NASA's Hubble Space Telescope. "Galaxies burn gas like a car engine burns fuel. Most galaxies have fairly inefficient engines, meaning they form stars from their stellar fuel tanks far below the maximum theoretical rate," said Jim Geach of McGill University, lead author of a new study appearing in the Astrophysical Journal Letters... The...
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The original prototype for the kilogram, stored under lock and key near Paris, appears to be losing weight. The cylinder, which dates back from 1889, seems to have lost 50 micrograms, compared with the average of dozens of copies of the original. Richard Davis, of the International Bureau of Weights and Measures in Sevres, said: "The mystery is that they were all made of the same material, and many were made at the same time and kept under the same conditions, and yet the masses among them are slowly drifting apart." The one in Sevres is the original that the...
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By JAMEY KEATEN, Associated Press Writer 6 minutes ago PARIS - A kilogram just isn't what it used to be. The 118-year-old cylinder that is the international prototype for the metric mass, kept tightly under lock and key outside Paris, is mysteriously losing weight — if ever so slightly. Physicist Richard Davis of the International Bureau of Weights and Measures in Sevres, southwest of Paris, says the reference kilo appears to have lost 50 micrograms compared with the average of dozens of copies. "The mystery is that they were all made of the same material, and many were made at...
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DENVER — The size of a proton, long thought to be well-understood, may remain a mystery for a while longer, according to physicists. Speaking today (April 13) at the April meeting of the American Physical Society, researchers said they need more data to understand why new measurements of proton size don't match old ones. "The discrepancy is rather severe," said Randolf Pohl, a scientist at the Max Planck Institute of Quantum Optics. The question, Pohl and his colleagues said, is whether the explanation is a boring one — someone messed up the measurements — or something that will generate new...
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