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Quantum world record smashed

Quantum world record smashed
14-Nov-2013 [ Print | E-mail ] Share [ Close Window ] Contact: University of Oxford Press Officepress.office@admin.ox.ac.uk 44-186-528-3877University of Oxford A normally fragile quantum state has been shown to survive at room temperature for a world record 39 minutes, overcoming a key barrier towards building ultrafast quantum computers. An international team including Stephanie Simmons of Oxford University, UK, report in this week's Science a test performed by Mike Thewalt of Simon Fraser University, Canada, and colleagues. In the experiment the team raised the temperature of a system, in which information is encoded in the nuclei of phosphorus atoms in silicon, from -269 °C to 25 °C and demonstrated that the superposition states survived at this balmy temperature for 39 minutes – outside of silicon the previous record for such a state's survival at room temperature was around two seconds. There is still some work ahead before the team can carry out large-scale quantum computations.

Gravitational-wave finding causes 'spring cleaning' in physics Detlev van Ravenswaay/Science Photo Library Artist's rendering of 'bubble universes' within a greater multiverse — an idea that some experts say was bolstered with this week's discovery of gravitational waves. On 17 March, astronomer John Kovac of the Harvard-Smithsonian Center for Astrophysics presented long-awaited evidence of gravitational waves — ripples in the fabric of space — that originated from the Big Bang during a period of dramatic expansion known as inflation. By the time the Sun set that day in Cambridge, Massachusetts, the first paper detailing some of the discovery’s consequences had already been posted online1, by cosmologist David Marsh of the Perimeter Institute for Theoretical Physics in Waterloo, Canada, and his colleagues. Cosmologist Marc Kamionkowski of Johns Hopkins University in Baltimore, Maryland, agrees that some axion models no longer work, “because they require inflation to operate at a lower energy scale than the one indicated by BICEP2”. Linde agrees.

The Puzzle of an Eternally-Existing, Self-Reproducing, and Inflationary Universe There are quite a few challenges for cosmologists trying to discover evidence of what it was like early in the life of our universe, but while the inflationary universe scenario was an almost universally accepted model, there are still problems, especially for observational astrophysicists who don’t see any evidence of a flat universe, as inflation would predict. What was previously accepted has now created some doubt, especially among the more abstract theorists. Inflation is based around a simple idea. Roger Penrose has argued that a universe like ours had to start out in a very particular state and that inflation by itself was not the final answer. The second problem is known as the measure problem, which tries to calculate the probabilities within the infinite ensemble of universes that eternal inflation creates. The final problem is called the holography/complementarity problem, which arose when physicists thought about black hole entropy and proposed horizon complementarity.

New Experiments to Pit Quantum Mechanics Against General Relativity It starts like a textbook physics experiment, with a ball attached to a spring. If a photon strikes the ball, the impact sets it oscillating very gently. But there’s a catch. Before reaching the ball, the photon encounters a half-silvered mirror, which reflects half of the light that strikes it and allows the other half to pass through. What happens next depends on which of two extremely well-tested but conflicting theories is correct: quantum mechanics or Einstein’s theory of general relativity; these describe the small- and large-scale properties of the universe, respectively. In a strange quantum mechanical effect called “superposition,” the photon simultaneously passes through and reflects backward off the mirror; it then both strikes and doesn’t strike the ball. But according to general relativity, gravity warps space and time around the ball. Knowing what happens to the ball could help physicists resolve the conflict between quantum mechanics and general relativity. Quantum Nature

Speed of Light May Not be Constant Posted March 26th, 2013 at 3:39 pm (UTC+0) Einstein’s famous equation (Image: Quatrostein via Wikimedia Commons) The speed of light has long been calculated to be 299,792.458 km per second, but now new research from France and Germany indicates that light may not travel at a fixed rate after all, but instead can fluctuate. A key component of Einstein’s famous E=MC2, the speed of light has been thought to be finite since 1676 after Danish astronomer Ole Rømer first established his findings while studying the motion of Jupiter’s moon Io. Danish astronomer Ole Rømer (Image: Frederiksborg Museum via Wikimedia Commons) Two separate studies by scientists from the University of Paris-Sud in France and from the Max Planck Institutes for the Physics of Light in Germany are disputing the long established belief concerning the nature of a vacuum. Researcher Marcel Urban and his colleagues in France said they had identified a “quantum level mechanism” for understanding vacuum. Gerd Leuchs and Luis L.

Carver Mead's Spectator Interview From American Spectator, Sep/Oct2001, Vol. 34 Issue 7, p68 Carver Mead The Spectator Interview Once upon a time, Nobel Laureate leader of the last great generation of physicists, threw down the gauntlet to anyone rash enough to doubt the fundamental weirdness, the quark-boson-muon-strewn amusement park landscape of late 20th-century quantum physics. Carver Mead never has. As Gordon and Betty Moore Professor of Engineering and Applied Science at Caltech, Mead was Feynman's student, colleague and collaborator, as well as Silicon Valley's physicist in residence and leading intellectual. Perhaps more than any other man, Mead has spent his professional life working on intimate terms with matter at the atomic and subatomic levels. While pursuing these researches, Mead responded to a query from Intel-founder Gordon Moore about the possible size of microelectronic devices. Among whom was Albert Einstein.

Chinese physicists measure Einstein's 'spooky action at a distance' speed: At least 10,000 times faster than light A team of Chinese physicists have clocked the speed of spooky action at a distance — the seemingly instantaneous interaction between entangled quantum particles — at more than four orders of magnitude faster than light. Their equipment and methodology doesn’t allow for an exact speed, but four orders of magnitude puts the figure at around 3 trillion meters per second. Spooky action at a distance was a term coined by Einstein to describe how entangled quantum particles seem to interact with each other instantaneously, over any distance, breaking the speed of light and thus relativity. Now, thanks to these Chinese physicists — the same ones who broke the quantum teleportation distance record last year — we know that spooky action at a distance has a lower bound of four orders of magnitude faster than light, or around 3 trillion meters per second. To get this figure, the physicists entangled pairs of photons at a base station, and then transmitted half of each pair to two receiving sites.

New qubit control bodes well for future of quantum computing (Phys.org)—Yale University scientists have found a way to observe quantum information while preserving its integrity, an achievement that offers researchers greater control in the volatile realm of quantum mechanics and greatly improves the prospects of quantum computing. Quantum computers would be exponentially faster than the most powerful computers of today. "Our experiment is a dress rehearsal for a type of process essential for quantum computing," said Michel Devoret, the Frederick William Beinecke Professor of Applied Physics & Physics at Yale and principal investigator of research published Jan. 11 in the journal Science. In quantum systems, microscopic units called qubits represent information. The Yale physicists successfully devised a new, non-destructive measurement system for observing, tracking and documenting all changes in a qubit's state, thus preserving the qubit's informational value. "As long as you know what error process has occurred, you can correct," Devoret said.

Mathematicians Extend Einstein's Theory of Special Relativity beyond Light Speed | Physics Mathematicians from University of Adelaide, Australia, have extended the theory of special relativity to work beyond the speed of light. Einstein’s theory holds that nothing could move faster than the speed of light. Published in 1905, the theory explains how motion and speed is always relative to the observer’s frame of reference. It connects measurements of the same physical incident viewed from these different points in a way that depends on the relative velocity of the two observers. “Since the introduction of special relativity there has been much speculation as to whether or not it might be possible to travel faster than the speed of light, noting that there is no substantial evidence to suggest that this is presently feasible with any existing transportation mechanisms,” said Prof Jim Hill of the University of Adelaide’s School of Mathematical Sciences, who co-authored a paper published in the Proceedings of the Royal Society A. Bibliographic information: James M.

New data confirms: Neutrinos are still traveling faster than light "It is worth pointing out, however, that the latest arXiv preprint lists 179 authors, while the original lists 174. Would you ever classify five people as "most of" 15? To make things more confusing . . . "four new people" have decided not to sign, according to Science. Now, none of the above numbers may match up . . .." The original 174 include a duplicate " F. The new 179 includes 10 new names that didn't appear on the old paper.

Philosophy begins where physics ends, and physics begins where philosophy ends | The Curious Wavefunction, Scientific American Blog Network The views expressed are those of the author and are not necessarily those of Scientific American. Richard Feynman - Philosopher (Image: Washington University) Physicist Sean Carroll has some words of wisdom for physicists who might have less than complimentary things to say about philosophy. The most recent altercation between a physicist and philosophy came from Neil deGrasse Tyson who casually disparaged philosophy in a Q&A session, saying that it can be a time sink and it doesn’t actually provide any concrete answers to scientific questions. Now I am willing to give Tyson the benefit of doubt since his comment was probably a throwaway remark; plus it’s always easy for scientists to take potshots at philosophers in a friendly sort of way, much like the Yale football team would take potshots at its Harvard counterpart. But Tyson’s response was only the latest in a series of run ins that the two disciplines have had over the past few years.

New Wormhole Theory Uses Space Photon Energy “Fluid” A new theory expands on other theories and adds photon energy “fluid” as a way to support wormholes. The introduction to the paper states the following. Wormholes are hypothetical geometrical structures connecting two universes or two distant parts of the same universe. For a simple visual explanation of a wormhole, consider spacetime visualized as a two-dimensional (2D) surface. If this surface is folded along a third dimension, it allows one to picture a wormhole “bridge”. [1] “A possible cause of the late-time cosmic acceleration is an exotic fluid with an equation of state lying within the phantom regime, i.e., w = p/ρ < −1. FIG. 1: The plot depicts the function H(x, a), for α = 1/2 and where the parameter x = r0/r, lying in the range 0 < x ≤ 1, has been defined in order to define the entire spacetime. By using this theory an advanced civilization would , in theory, be able to mine photon “fluid” for Phantom Energy to construct micro worm holes for such things as transportation. Related

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