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Submission + - Some physical properties are undecidable (nature.com)

wheelbarrio writes: In a paper titled "Undecidability of the spectral gap" published last week in Nature, three theoretical computer scientists demonstrate that at least one important characteristic of a physical system is axiomatically unprovable. Specifically, the presence or absence of a non-zero spectral gap — the difference in energy between the ground state and first excited state of a quantum system — cannot derived from first principles. The proof involves constructing a correspondence between the calculation of the spectral gap and the Turing machine halting problem. Unless a loophole is found this is a profoundly distressing result for physicists, and it means that the sixth Clay Millennium Prize problem (Yang-Mills mass gap) is insoluble.

Submission + - Huge Jupiter-Like Storm Rages On Cool 'Failed Star' (discovery.com)

astroengine writes: Jupiter’s Big Red Spot is the largest example of a long-lived storm in the solar system, but now it has some pretty stiff competition in another star system. However, this “exo-storm” hasn’t been spied on another gas giant, it’s been spotted in the uppermost layers of a cool, small "failed star" or brown dwarf. Using 3 NASA space telescopes, new research published in The Astrophysical Journal has found that this spot isn't a starspot, but a bona fide storm that has more in common with Jupiter's famous cyclone. So is this REALLY a failed star? Or is is an "overachieving planet"?

Submission + - Simple robots, complex behaviors: A controls perspective on Braitenberg Vehicles (robohub.org)

Hallie Siegel writes: Valentino Braitenberg was a neuroscientist and cyberneticist who used very simple electro-mechanical vehicles as a way to communicate how animal psychology could have evolved. His thought exercises, generally referred to as Braitenberg Vehicles, begin as a single sensor connected directly to a single actuator and evolve through multiple iterations into vehicles that can remember, have the ability to predict, and develop an ego. Controls expert Brian Douglas takes us through an informative and well-paced video tutorial on Braitenberg's concepts and how they apply to control systems.

Submission + - Scientists Invent a New Steel as Strong as Titanium (popularmechanics.com) 1

schwit1 writes: South Korean researchers have solved a longstanding problem that stopped them from creating ultra-strong, lightweight aluminum-steel alloys.

Today a team of material scientists at Pohang University of Science and Technology in South Korea announced what they're calling one of the biggest steel breakthroughs of the last few decades: an altogether new type of flexible, ultra-strong, lightweight steel. This new metal has a strength-to-weight ratio that matches even our best titanium alloys, but at one tenth the cost, and can be created on a small scale with machinery already used to make automotive-grade steel. The study appears in Nature.

Submission + - It wasn't just an asteroid that killed the dinosaurs

schwit1 writes: Scientists have now obtained enough solid data to confirm that the large extinction of the dinosaurs 65 million years ago was caused not just by the Yucatan asteroid impact but also by the gigantic volcanic event in India called the Deccan Traps.

The researchers said the asteroid strike occurred 66.04 million years ago, plus or minus about 30,000 years. They said eruptions in a region called the Deccan Traps were already underway at a lower intensity but dramatically accelerated after the asteroid strike as if the powerful impact triggered it. The dating method they used found this acceleration began within 50,000 years of the impact, but it could have been in the mere days, months or years afterward. "Within measurement error, they're simultaneous," said volcanologist Loyc Vanderkluysen of Philadelphia's Drexel University. "The two processes in tandem caused the extinctions," added Paul Renne, director of the Berkeley Geochronology Center and a University of California, Berkeley geologist, who led the study in the journal Science.

Though many planetary scientists have discounted the Deccan Traps for decades, paleontologists have tended to favor it as a major factor in the extinction. This new study suggests that both were involved, which was the theory held by most of the more reasonable scientists in both fields. While many liked to push one or the other theory in the press, the better scientists considered both a possible factor and have been working to determine this possibility.

Submission + - Have The Robots Broken The Stock Market? (seekingalpha.com)

walterbyrd writes: The markets were sloppy last week, and we went out on a bad note. Sentiment was very negative. And when Chinese stocks continued to crash on Sunday, it looked like we might be on the verge of something nasty. Uncertainty was everywhere. And then the robots took control. I watched the futures market almost all night on Sunday, and we were seeing 100-point moves in the Dow Futures contract within a few minutes. This was not human controlled. And it was not rational.

Submission + - Federal Court Overturns Ruling that NSA Metadata Collection was Illegal (npr.org)

captnjohnny1618 writes: *Sigh* NPR is reporting that an appeals court has overturned the decision that the NSA's bulk data collection was illegal.


A three judge panel for a U.S. appeals court has thrown out a lower-court decision that sought to stop the NSA from continuing to collect metadata on phone calls made by Americans.
>br> The lower court ruling had found that the practice was unconstitutional.

They go on to clarify that due to the recent passage of new laws governing how metadata is collected, this is less of a significant point than it would have otherwise been:

In some ways, this decision is much less important now that Congress has passed a law that changes the way meta-data is collected by the government. If you remember, after a fierce battle, both houses of Congress voted in favor of a law that lets phone companies keep that database, but still allows the government to query it for specific data.

Still seems like a fairly significant decision to me: in one case a government agency was willfully and directly violating the rights of the Americans (and international citizens as well) and now it's just going to get shrugged off?

One step forward and two back...

Submission + - Extreme Pressure Reveals New Phenomenon in Atomic Nuclei (gizmag.com)

Zothecula writes: Scientists have long believed that while an atom's outer electrons are highly mobile and often behave somewhat chaotically, the inner electrons close to the nucleus are stable. They move steadily around the nucleus and stay out of each other's way. But new research reveals that if the pressure is really extreme, like double that found at the center of the Earth, the innermost electrons of an atom change their behavior.

Submission + - More than half of psychological results can't be reproduced (independent.co.uk)

Bruce66423 writes: A new study trying to replicated results reported in allegedly high quality journals failed to do so in over 50% of cases. Those of us from a hard science background always had our doubts about this sort of stuff — it's interesting to see it demonstrated — or rather, as the man says: "Psychology has nothing to be proud of when it comes to replication,” Charles Gallistel, president of the Association for Psychological Science.

Submission + - NASA spies Earth-sized exoplanet orbiting Sun-like star

An anonymous reader writes: NASA has announced that a new Earth like planet has been discovered that may be the closest thing yet to a first true "Earth twin". Kepler 452b, is located 1,000 light years away, is 60% larger than Earth, and orbits Kepler 452 at a distance similar to that between Earth and the Sun. “It is the first terrestrial planet in the habitable zone around a star very similar to the Sun,” says Douglas Caldwell, an astronomer at the SETI Institute in Mountain View, California.

Submission + - Open-Source Mesa 3D Library/Drivers Now Support OpenGL 4 (phoronix.com)

An anonymous reader writes: The Mesa 3D project that is the basis of the open-source Linux/BSD graphics drivers now supports OpenGL 4.0 and most of OpenGL 4.1~4.2. The OpenGL 4.0 enablement code landed in Mesa Git yesterday/today and more GL 4.1/4.2 patches are currently being reviewed for the Intel, Radeon, and Nouveau open-source GPU drivers.

Submission + - Smartphone apps fraudulently collecting revenue from invisible ads (bloomberg.com)

JoeyRox writes: Thousands of mobile applications are downloading ads that are never presented to users but which collect an estimated $850 million in fraudulent revenue from advertisers per year. The downloading of these invisible ads can slow down users' phones and consume up to 2GB of bandwidth per day. Forensiq, an online technology firm fighting fraud for advertisers, found over 5,000 apps displayed unseen ads on both Apple and Android devices. "The sheer amount of activity generated by apps with fake ads was what initially exposed the scam. Forensiq noticed that some apps were calling up ads at such a high frequency that the intended audience couldn’t possibly be actual humans".

Submission + - MIT Stealth Startup Charges Up Wireless Power Competition (xconomy.com)

gthuang88 writes: Wireless charging of electronics is an old concept, but there’s a new player in the competition between companies like WiTricity, Energous, and tech giants Apple, Samsung, and Qualcomm. A new spinout from Dina Katabi’s lab at MIT, called Pi, may have a new take on how to charge mobile devices at a distance. The company isn’t talking yet, but Katabi’s research suggests the system uses an array of coils to produce a magnetic field and detect when a device is within range, like a Wi-Fi router. The array can then focus the magnetic field on a coil attached to a phone or mobile device and induce a current to charge the battery. But it’s still very early, and the field of wireless charging needs to settle on technical standards and work out its commercial kinks.

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