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The superfow of two kinds of superconducting electrons (arrows show their velocities) as calculated on supercomputers. Graphic 2 shows superflow of the other subpopulation of electrons on the surface of a vortex cluster. Graphics courtesy of Egor Babaev.
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The bubble nebula NGC 7635 - it doesn't have a lot to do with Holographic Dark Information Energy, but you have to start these articles with an image. Credit: Croman/an APOD for November 7 2005. Holographic Dark Information Energy gets my vote for the best mix of arcane theoretical concepts expressed in the shortest number of words – and just to keep it interesting, it’s mostly about entropy. The second law of thermodynamics requires that the entropy of a closed system cannot decrease. So drop a chunk of ice in a hot bath and the second law requires that the ice melts and the bath water cools – moving the system from a state of thermal disequilibrium (low entropy) towards a state of thermal equilibrium (high entropy). In an isolated system (or an isolated bath) this process can only move in one direction and is irreversible.
The human nervous system consists of billions of nerve cells (or neurons) plus supporting (neuroglial) cells. Neurons are able to respond to stimuli (such as touch, sound, light, and so on), conduct impulses, and communicate with each other (and with other types of cells like muscle cells).
Two independent groups of physicists have unveiled the first phonon "lasers" – devices that emit coherent sound waves in much the same ways as lasers emit coherent light waves. Sometimes called "sasers", one of the devices emits sound at about 400 GHz while the other operates in the megahertz range. Such very high frequency sound could be used to probe the interiors of tiny objects – and the ability to create laser-like beams of sound could lead to new imaging applications. Indeed, the differences between the two devices suggest that sasers could be made to operate over a wide range of frequencies. At the heart of any optical laser is a medium with an electronic transition that involves the emission of a photon.
Processes taking place in outer space, and not on Earth, are likely to have led to the biological molecules found exclusively in either a left-handed or right-handed form. That is the conclusion drawn from recent experiments carried out at the SOLEIL synchrotron facility near Paris in which a number of simple molecules found in star-forming regions exposed to polarized radiation created amino acids with an imbalance of left- and right-handed molecules. So-called chiral molecules can exist in two forms, with one being the non-superimposable mirror-image of the other, even though both have the same chemical make-up. Although laboratory experiments will tend to produce equal quantities of the left- and right-handed versions of a given chiral molecule, many of the chiral molecules found in living organisms come in only one variety. For example, the amino acids that make up proteins only exist in the left-handed form, while the sugars found in DNA are exclusively right-handed.
Physicists in the UK have created a Luneburg lens – a lens able to focus light from all directions equally well – on a silicon chip. The device could one day find applications in on-chip Fourier optics, which are used by the telecoms industry to perform tasks from noise reduction to data compression. Most practical lenses have aberrations, which means that their ability to focus light deteriorates when the incident light is off-axis.
Physicists in the US claim to have broken the record for the brightness of light generated by “sonoluminescence”, the imploding of a bubble when it is blasted with sound waves. With a peak power of 100 W, the light is 100 times as bright as seen in previous sonoluminescence experiments, and may help scientists understand how the strange phenomenon works. Sonoluminesence was discovered in the first half of the 20th century but it was only in the 1990s that physicists began to investigate the phenomenon seriously. Although no-one is sure how it works, the basic idea is that sound waves are fed into a vessel containing one or more bubbles inside a liquid.
Milo Wolff, M.I.T (retired) 1125 Third Street, Manhattan Beach, CA 90266 Milo.Wolff@QuantumMatter.com
Published: December 12, 2004
As of 2008, the United States Department of Energy (DOE) and other U.S. federal agencies have spent approximately 18 billion dollars on energy devices using the fusion reaction between deuterium and tritium (D-T Fusion, below left).
Just over a year ago several media outlets reported that John Kanzius, an amateur inventor from Erie, Pa., had discovered a seemingly impossible phenomenon: a way to burn salt water by exposing it to radio waves. Videos of the experiment became YouTube sensations, though they garnered as many critical comments as favorable ones.
31 March 2011 Last updated at 15:27 GMT By Jonathan Amos Science correspondent, BBC News, Munich It looks like a giant potato in space, and yet the information in this model is the sharpest view we have of how gravity varies across the Earth. The globe has been released by the team working on Europe's Goce satellite.
Scientists are trying to find out if, in addition to a molecule's shape, its vibrational energy also plays a role in how we distinguish smells. Image is part of an 1895 painting by John William Waterhouse. (PhysOrg.com) -- Since 1996, when biophysicist Luca Turin first suggested that quantum mechanics may help explain how we smell various odors, the idea has met with controversy.
Én af topmedarbejderne hos søgemaskinegiganten Google, Corinna Cortes, tiltræder i dag som adjungeret professor på Datalogisk Institut ved Københavns Universitet. Danske Corinna Cortes er til daglig leder af Google Research i New York, USA, men skal fremover også stå til rådighed for universitetet med sin viden om 'machine learning', eller maskinlæring. Et forskningsområde, som i praksis benyttes til at optimere søgeresultaterne i søgemaskiner som Google og Yahoo.