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Submission + - Scientists Finally Turn Hydrogen Into a Metal, Ending a 80-Year Quest (

An anonymous reader writes: In 1935, scientists predicted that the simplest element, hydrogen, could also become metallic under pressure, and they calculated that it would take 25 GigaPascals to force this transition (each Gigapascal is about 10,000 atmospheres of pressure). That estimate, in the words of the people who have finally made metallic hydrogen, "was way off." It took until last year for us to reach pressures where the normal form of hydrogen started breaking down into individual atoms—at 380 GigaPascals. Now, a pair of Harvard researchers has upped the pressure quite a bit more, and they have finally made hydrogen into a metal. All of these high-pressure studies rely on what are called diamond anvils. This hardware places small samples between two diamonds, which are hard enough to stand up to extreme pressure. As the diamonds are forced together, the pressure keeps going up. Current calculations suggested that metallic hydrogen might require just a slight boost in pressure from the earlier work, at pressures as low as 400 GigaPascals. But the researchers behind the new work, Ranga Dias and Isaac Silvera, discovered it needed quite a bit more than that. In making that discovery, they also came to a separate realization: normal diamonds weren't up to the task. "Diamond failure," they note, "is the principal limitation for achieving the required pressures to observe SMH," where SMH means "solid metallic hydrogen" rather than "shaking my head." The team came up with some ideas about what might be causing the diamonds to fail and corrected them. One possibility was surface defects, so they etched all diamonds down by five microns to eliminate these. Another problem may be that hydrogen under pressure could be forced into the diamond itself, weakening it. So they cooled the hydrogen to slow diffusion and added material to the anvil that absorbed free hydrogen. Shining lasers through the diamond seemed to trigger failures, so they switched to other sources of light to probe the sample. After loading the sample and cranking up the pressure (literally—they turned a handcrank), they witnessed hydrogen's breakdown at high pressure, which converted it from a clear sample to a black substance, as had been described previously. But then, somewhere between 465 and 495 GigaPascals, the sample turned reflective, a key feature of metals

Submission + - First Experimental Demonstration of a Trapped Rainbow Using Silicon

KentuckyFC writes: Back in 1947, a pair of physicists demonstrated that when a beam of light reflects off a surface, the point of reflection can shift forward when parts of the beam interfere with each other. 60 years later, another group of physicists discovered that this so-called Goos-Hanchen effect could sometimes be negative so the point of reflection would back towards the source rather than away from it. They even suggested that if the negative effect could be made big enough, it could cancel out the forward movement of the light. In other words, the light would become trapped at a single location. Now, physicists have demonstrated this effect for the first time using light reflected of a sheet of silica. The trick they've employed is to place a silicon diffraction grating in contact with the silica to make the interference effect large enough to counteract the forward motion of the light. And by using several gratings with different spacings, they've trapped an entire rainbow. The light can be easily released by removing the grating. Until now, it has only been possible to trap light efficiently inside Bose Einstein Condensate at temperatures close to absolute zero. The new technique could be used as a cheap optical buffer or memory, making it an enabling technology for purely optical computing.

Submission + - YouTube to Remove Scientist's Account who Debunked AIDS Deniers Movie (

EwanPalmer writes: YouTube is threatening to remove the account of a scientist who made a series of videos debunking claims made in an Aids denialist movie over copyright infringement disagreement.

Myles Power is claiming the producers of controversial 2009 documentary House of Numbers are attempting to censor him by submitting bogus DMCA claims against him. He says his movies do not breach copyright laws because his films are educational and therefore fair use. The 'AIDS denialist' documentary makers say they instead amounted to “propaganda”.

Submission + - Hubble spots source of short GRB (

symbolset writes: Researchers using the Hubble Space Telescope have imaged some evidence that the merger of neutron stars is responsible for producing a short-duration gamma ray burst. On June 3rd the Swift gamma-ray burst (GRB) mission detected GRB 130603B, a burst lasting only one tenth of a second nearly 4 billion lightyears away. Imaging with Hubble they located a small red dot which, over the course of the following two weeks dimmed. Cites an article in yesterday's special online edition of Nature.

Submission + - Less vaccination then, more measles now (

DavidHumus writes: Some of the longer-term effects of the anti-vaccination movement of past decades is now evident in a dramatic increase in measles. From the article: A measles outbreak infected 1,219 people in southwest Wales between November 2012 and early July, compared with 105 cases in all of Wales in 2011.

There continues to be no credible evidence that vaccination causes autism but the a significant minority believes this anyway.

Submission + - Some volcanoes 'scream' at ever-higher pitches until they blow their tops (

vinces99 writes: Swarms of small earthquakes often precede a volcanic eruption. They can reach such rapid succession that they create a "harmonic tremor" that resembles sound made by some musical instruments. A new analysis of an eruption sequence at Alaska's Redoubt Volcano in March 2009 shows the harmonic tremor glided to substantially higher frequencies and then stopped abruptly just before six of the eruptions. Scientists at the U.S. Geological Survey's Alaska Volcano Observatory have dubbed the highest-frequency harmonic tremor at Redoubt Volcano “the screams” because the episodes reach such high pitch compared with a 1-to-5 hertz starting point. Alicia Hotovec-Ellis, a University of Washington doctoral student in Earth and space sciences and an author of two papers examining the phenomenon, has created a 10-second recording and a one-minute recording that provides a 60-times faster representation of harmonic tremor and small earthquakes.

Submission + - Judge Orders Porn Suspect to Decrypt His Hard Drives 2

An anonymous reader writes: After having first decided against forcing a suspect to decrypt a number of hard drives that were believed to be his and to contain child pornography, a U.S. judge has changed his mind and has now ordered the suspect to provide law enforcement agents heading the investigation with a decrypted version of the contents of his encrypted data storage system, or the passwords needed to decrypt forensic copies of those storage devices. Jeffrey Feldman, a software developer at Rockwell Automation, has still not been charged with any crime, and the prosecution initially couldn't prove conclusively that the encrypted hard drives contained child pornography or were actually Feldman's, which led U.S. Magistrate Judge William Callahan to decide that forcing him to decrypt them would violate his Fifth Amendment right against self-incrimination.

Submission + - New island appears off coast of Germany ( 4

quantumghost writes: Despite its youthful age the sickle-shaped island lying 16 miles off the coast of the German state of Schleswig Holstein is already home to around 50 different plant species and proved popular with sea birds such as herring gulls and oyster catchers, eager to take advantage of its unspoilt and pristine environment.

Formed over just 10 years, the rapid appearance of the island has surprised scientists familiar with the strong winds and shifting shifts that characterise Germany's North Sea coast.


Submission + - The hidden truths about calories (

Raindance writes: "Scientific American recently explored how the traditional way of calculating calories has failed to keep up with science: "When the calorie was originally conceived it was in the context of human work ... chemical fire with which to get the job done, coal in the human stove. Fat, it has been estimated, has nine calories per gram, whereas carbohydrates and proteins have just four; fiber is sometimes counted separately and gets awarded a piddling two. Every box of every food you have ever bought is labeled based on these estimates; too bad then that they are so often wrong."

The NYT has some suggestions to improve and broaden our current labeling system, while others seem to feel the task of defining a healthy diet should be taken away from nutritionists and given to gut flora microbiologists. What's Slashdot's dream label?"


Submission + - DARPA working on grave-robbing Frankenstein satell ( 1

MrSeb writes: "Just in time for Halloween, DARPA has published details of a new satellite that will allow scientists to create Frankensteinian satellites out of dead communications equipment currently orbiting the Earth. Right now there are about 19,000 different pieces of space debris in both low and high orbit around the planet, creating a dangerous scenario for both space flight and expensive items like the Hubble space telescope. Aptly named Phoenix, the idea is simple with a complex implementation. Using re-purposed robot arms from assembly lines and surgery units to create the scavenger bot, Phoenix will be shot into space and placed in the “graveyard” orbit that all the dead satellites are on as well. From there, it will attach to these units, and cut away different components to be used to create new, working units to be placed back into useful service. Phoenix is slated to launch in 2015 for testing, but there are some hurdles to its success, namely the Outer Space Treaty that states that an object launched into orbit remains the property of the country that put it there."

Submission + - Al Gore, 24 Hours of Reality - Faked?!?! (

sanzibar writes: This is one climate finding that all should agree on.

In his "Climate 101" video, Al Gore decided he would put to rest once and for all the theory that cO2 causes warming. It was a simple experiment — one glass with cO2, the other without, record the temperatures. To no ones surprise, the glass with cO2 increased in temperature. The controversy? It was fabricated. Hit the link for the full scoop from Slashdot Reader — Anthony Watts.

"I should make it clear that I’m not doubting that CO2 has a positive radiative heating effect in our atmosphere, due to LWIR re-radiation, that is well established by science. What I am saying is that Mr. Gore’s Climate Reality Project did a poor job of demonstrating an experiment, so poor in fact that they had to fabricate portions of the presentation, and that the experiment itself (if they actually did it, we can’t tell) would show a completely different physical mechanism than what actually occurs in our atmosphere. If Mr. Gore wants to convince the world, he’d do far better at emulating the Mythbusters TV show; show all the materials, steps, measurement, and results like they do." — Anthony Watts


Submission + - Thermite Reaction Responsible For WTC Collapse? ( 6

esocid writes: Christian Simensen, a senior SINTEF scientist believes that heat melted the aluminium of the aircraft hulls, and the core of his theory is that molten aluminium then found its way downwards within the buildings through staircases and gaps in the floor – and that the flowing aluminium underwent a chemical reaction with water from the sprinklers in the floors below. “Both scientific experiments and 250 reported disasters suffered by the aluminium industry have shown that the combination of molten aluminium and water releases enormous explosions,” says Simensen.

"Alcoa Aluminium carried out an experiment under controlled conditions, in which 20 kilos of aluminium smelt were allowed to react with 20 kilos of water, to which some rust was added. The explosion destroyed the entire laboratory and left a crater 30 metres in diameter." Extrapolate that to the 30 tons from the planes, and his theory has some weight to it, no pun intended. The article was published in the trade magazine


Submission + - SeaTwirl Puts a New Spin on Offshore Wind Turbines (

Zothecula writes: One of the main drawbacks of wind turbines is the fact that for maximum efficiency, the power that they generate must be fed into the grid right as the wind is blowing and their blades are spinning. While that power can be stored in batteries for later use, some of it will always be lost in the process. Sweden's experimental new SeaTwirl system, however, is designed to kinetically store wind energy until it's required — it's basically a seagoing flywheel.

Submission + - Printing your own restricted gun parts: legal? (

CaVp writes: For all of you gun and 3D printing lovers, Thingiverse (3d digital design projects heaven) has a project for printing the lower receiver for the AR-15, the only part of this gun that requires some paperwork to buy; according to the article:

The Lower Receiver is the frame that holds together all the other pieces of the firearm. In the States, all the other pieces can be purchased without a permit — over the counter or through the post. The Lower Receiver is the only part which requires a background check or any other kind of paperwork before purchase.

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