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StartsWithABang (3485481) writes "Back in the 1960s, after the discovery of the Cosmic Microwave Background, the Big Bang reigned supreme as the only game in town. But back then, we also assumed that what we consider as "normal matter" — i.e., protons, neutrons and electrons — was, along with photons and neutrinos, the only stuff that made up the Universe. But the last 50 years have shown us that dark matter and dark energy actually make up 95% of the energy composition of our cosmos. Given that, is there any wiggle room to possibly invalidate the Big Bang?"

StartsWithABang (3485481) writes It's finally here! Sure, we witnessed the birth of a new meteor shower earlier this year, but it was a flop. Many other showers have come-and-gone like they do every year, but none of them have given us a significant number of meteors-per-hour. But even with a near-full Moon out, it's finally time for the Perseids, the most reliable meteor shower year-after-year. Here's where to find them, where they come from and a whole lot more, including some surprising facts about where they don't come from: cometary tails!

KentuckyFC (1144503) writes One curious property of massless particles like photons is that their energy or momentum can take any value across many orders of magnitude, a property that physicists call scale invariance. By contrast, massive particles like electrons always have the same mass regardless of their energy or momentum. So massive particles are not scale invariant. The concept of unparticles is the idea that some "stuff" may have mass, energy and momentum and yet also be scale invariant. This stuff must be profoundly different from ordinary particles, hence the name: unparticles. Nobody has ever seen an unparticle but now physicists are suggesting that unparticles may hold the key to understanding unconventional superconductivity. Their thinking is that at very low temperatures, ordinary particles can sometimes behave like unparticles. In other words, their properties become independent of the scale at which they're observed. So if an unparticle moves without resistance on a tiny scale, then it must also move without resistance at every scale, hence the phenomenon of superconductivity. That could provide some important insights into unconventional superconductivity which has puzzled physicists since it was discovered in the 1980s.

StartsWithABang writes Just over a century ago, N rays were detected by over a hundred researchers and discussed in some three hundred publications, yet there were serious experimental flaws and experimenter biases that were exposed over time. Fast forward to last week, and NASA Tests Microwave Space Drive is front page news. But a quick analysis shows that it isn't theorists who'll need to struggle to explain this phenomenon, but rather the shoddy experimentalists who are making the exact same "bad science" mistakes all over again.

KentuckyFC (1144503) writes Researchers from Cornell University glued a tiny magnetic bar to the back of fruit flies and allowed them to fly through an electromagnet. Pulsing the magnet then causes the flies to roll in mid-air, like victorious Spitfire pilots. The work isn't entirely frivolous. The team was studying how fruit flies achieve stable flight when they ought to be particularly susceptible to being rolled by tiny gusts of air.

It turns out that fruit flies have incredibly fast reactions. They respond to being rolled within a single wing beat, that's 5 milliseconds, flapping their wings asymmetrically to regain stable flight. That kind of reaction time makes them one of the fastest creatures in the animal world. By comparison, the visual startle response in flies takes 20 milliseconds and the quickest reactions humans can manage is about 100 milliseconds.

StartsWithABang (3485481) writes Based on all the experiments we've ever been able to perform, we're quite certain that our Universe, from the largest scales down to the microscopic, obeys the physical laws of three spatial dimensions (and one time dimension): a four-dimensional spacetime. But that's not the only possibility mathematically. People had experimented with bringing a fifth dimension in to unify General Relativity with Electromagnetism in the past, but that was regarded as a dead-end. Then in the 1970s, an unknown theoretical physicist working on the string model of the strong interactions discovered that by going into the 26th dimension, some incredibly interesting physics emerged, and String Theory was born.

KentuckyFC writes In a classic The Far Side cartoon by Gary Larson, a group of cows stand on two legs chatting by the side of a road when a lookout shouts "car". The cows immediately drop to a four-legged stance as the car passes by and return to their usual position and continue chatting when it has gone. Now a team of animal behavior specialists have discovered that the social lives of cattle are more complex than biologists had ever imagined (although not quite into Larson territory). These guys attached RFID tags to 70 Holstein-Fresian calves kept in three pens. They then monitored the position of each cow for a week to see which other animals they tended to have contact with. This allowed them to construct the social network for the cows with unprecedented detail. It turns out these social networks have many of the properties of human social networks. Cows have preferred partners who they tend to spend more time with and 60 per cent of their contacts occur during feeding which amounts to only 6 per cent of their time. The work has important applications. It should help biologists more accurately model how disease spreads through herds of cattle and therefore better understand how to tackle epidemics.

gallifreyan99 writes: Every drug you take will have been tested on people before it—but that testing process is meant to be tightly controlled, for the safety of everyone involved. Two investigations document the questionable methods used in many studies, and the lack of oversight the FDA seems to have over the process. First, drugs are increasingly being tested on homeless, destitute and mentally ill people. Second, it turns out many human trials are being run by doctors who have had their licenses revoked for drug addiction, malpractice and worse.

gallifreyan99 writes: Every drug you take will have been tested on people before it—but that testing process is meant to be tightly controlled, for the safety of everyone involved. Two investigations document the questionable methods used in many studies, and the lack of oversight the FDA seems to have over the process. First, drugs are increasingly being tested on homeless, destitute and mentally ill people. Second, it turns out many human trials are being run by doctors who have had their licenses revoked for drug addiction, malpractice and worse.

schwit1 writes: "With a drive of 157 feet on Sunday, the Mars rover Opportunity broke the Soviet record, set by Lunokhod 2 in 1973, for the longest distance traveled by a vehicle on another planet. "If the rover can continue to operate the distance of a marathon — 26.2 miles (about 42.2 kilometers) — it will approach the next major investigation site mission scientists have dubbed "Marathon Valley." Observations from spacecraft orbiting Mars suggest several clay minerals are exposed close together at this valley site, surrounded by steep slopes where the relationships among different layers may be evident. The Russian Lunokhod 2 rover, a successor to the first Lunokhod mission in 1970, landed on Earth's moon on Jan. 15, 1973, where it drove about 24.2 miles (39 kilometers) in less than five months, according to calculations recently made using images from NASA's Lunar Reconnaissance Orbiter (LRO) cameras that reveal Lunokhod 2's tracks."

An anonymous reader writes "Sunday was the birthday of the late great Gary Gygax, co-creator of Dungeons & Dragons and Futurama guest star. With the fifth edition of D&D soon to come out at Gen Con this year, Jon Peterson, author of Playing at the World, has released a new piece to answer a historical question: how was it, back in 1985, that Gary was ousted from TSR and control of D&D was taken away from him? Drawn from board meeting minutes, stock certificates, letters, and other first-hand sources, it's not a quick read or a very cheery one, but it shows how the greatest success of hobby games of the 1980s fell apart and marginalized its most famous designer."

StartsWithABang (3485481) writes On Wednesday, The Washington Post ran a story about a very large solar flare two years ago that missed Earth, but not by too much. From a scientific point of view, what is it that happens when a solar flare interacts with Earth, and what are the potential dangers to both humans and humanities infrastructure? A very good overview, complete with what you can do — as both an individual and a power company — to minimize the risk and the damage when the big one comes. Unlike asteroids, these events happen every few centuries, and in our age of electronics, would now create a legitimate disaster.

KentuckyFC (1144503) writes Black holes are singularities in spacetime formed by stars that have collapsed at the end of their lives. But while black holes are one of the best known ideas in cosmology, physicists have never been entirely comfortable with the idea that regions of the universe can become infinitely dense. Indeed, they only accept this because they can't think of any reason why it shouldn't happen. But in the last few months, just such a reason has emerged as a result of intense debate about one of cosmology's greatest problems — the information paradox. This is the fundamental tenet in quantum mechanics that all the information about a system is encoded in its wave function and this always evolves in a way that conserves information. The paradox arises when this system falls into a black hole causing the information to devolve into a single state. So information must be lost.

Earlier this year, Stephen Hawking proposed a solution. His idea is that gravitational collapse can never continue beyond the so-called event horizon of a black hole beyond which information is lost. Gravitational collapse would approach the boundary but never go beyond it. That solves the information paradox but raises another question instead: if not a black hole, then what? Now one physicist has worked out the answer. His conclusion is that the collapsed star should end up about twice the radius of a conventional black hole but would not be dense enough to trap light forever and therefore would not be black. Indeed, to all intents and purposes, it would look like a large neutron star.

KentuckyFC (1144503) writes When animals lose a limb, they learn to hobble remarkably quickly. And yet when robots damage a leg, they become completely incapacitated. That now looks set to the change thanks to a group of robotics engineers who have worked out how to dramatically accelerate the process of learning to walk again when a limb has become damaged. They've tested it on a hexapod robot which finds an efficient new gait in under two minutes (with video), and often faster, when a leg becomes damaged. The problem for robots is that the parameter space of potential gaits is vast. For a robot with six legs and 18 motors, the task of finding an efficient new gait boils down to a search through 36-dimensional space. That's why it usually takes so long. The new approach gets around this by doing much of this calculation in advance, before the robot gets injured. The solutions are then ordered according to the amount of time each leg remains in contact with the ground. That reduces the dimension of the problem from 36 to 6 and so makes it much easier for the robot to search. When a leg becomes damaged, the robot selects new gaits from those that minimize contact with the ground for the damaged limb. It compares several and then chooses the fastest. Voila! The resulting gaits are often innovative, for example, with the robot moving by springing forward. The new approach even found a solution should all the legs become damaged. In that case, the robot flips onto its back and inches forward on its "shoulders."

KentuckyFC (1144503) writes The idea of negative mass has fascinated scientists since it was first used in the 16th century to explain why metals gain weight when they are oxidized. Since then, theoretical physicists have shown how it could be used to create exotic objects such as wormholes and the Alcubierre warp drive. But cosmologists' attempts to include negative matter in any reasonable model of the cosmos have always run into trouble because negative mass violates the energy conditions required to make realistic universes with Einstein's theory of general relativity. Now a pair of cosmologists have found a way around this. By treating negative mass as a perfect fluid rather than a solid point-like object, they've shown that negative mass does not violate the energy conditions as had been thought, and so it must be allowed in our universe. That has important consequences. If positive and negative mass particles were created in the early universe, they would form a kind of plasma that absorbs gravitational waves. Having built a number of gravitational wave observatories that have to see a single gravitational wave, astronomers might soon need to explain the absence of observations. Negative mass would then come in extremely handy.

KentuckyFC (1144503) writes When Japan's Hayabusa spacecraft gently maneuvered into a parking orbit around the asteroid Itokawa in September 2005, it conducted a comprehensive photographic survey, the most detailed ever taken of an asteroid. This survey revealed that Itokawa is covered in large boulders that look like ejecta from craters in other parts of the asteroid. But when astronomers added up the total volume of these boulders, it turned out to be greater than the volume of the craters there were supposed to have come from. Other asteroids also show a similarly skewed distribution of large boulders. That has caused some significant head-scratching among astronomers who are at a loss to explain where the boulders come from.

Now an international team has solved the mystery. They say the boulders float to the surface of asteroids in an astrophysical example of the Brazil nut effect. This is the long observed phenomenon in which shaking a mixture of big and small particles causes the larger ones to rise to the top. That's because the shaking creates gaps beneath the large particles that small particles fall into. The result is that the large particles float. The team simulated the shaking effect that collisions between asteroids would produce and say that these vibrations would cause large boulders to float to the surface in a few hours, finally explaining why asteroids have such boulder-strewn surfaces. Problem solved!

StartsWithABang writes Our observable Universe is a pretty impressive entity: extending 46 billion light-years in all directions, filled with hundreds of billions of galaxies and having been around for nearly 14 billion years since the Big Bang. But what lies beyond it? Sure, there's probably more Universe just like ours that's unobservable, but what about the multiverse? Finally, a treatment that delineates the difference between the ideas that are thrown around and explains what's accepted as valid, what's treated as speculative, and what's completely unrelated to anything that could conceivably ever be observed from within our Universe.

KentuckyFC writes: On 13 March 1989, a powerful geomagnetic storm severely disrupted the Hydro-Québec high-voltage grid triggering numerous circuit breakers and blacking out much of eastern Canada and the northeastern U.S. Since then, Earth has been hit by numerous solar maelstroms without such large-scale disruption. But the smaller-scale effect of these storms on low voltage transmissions lines, and the equipment connected to them, has been unknown. Until now. Researchers from the Lockheed Martin Solar and Astrophysics Laboratory have analyzed insurance claims for damage to industrial electrical equipment between 2000 and 2010 and found a clear correlation with geomagnetic activity. They say that the number of claims increases by up to 20 per cent on the days of highest geomagnetic activity. On this basis, they calculate that the economic impact of geomagnetic damage must amount to several billion dollars per year. That raises the question of the impact these storms have on household electronic equipment, such as computers, smartphones and tablets, and whether domestic insurance claims might throw some light on the issue.

KentuckyFC (1144503) writes "In the 1970 World Cup in Mexico, teams used a new kind of ball called the Telstar made from 12 black pentagonal panels and 20 white hexagonal panels. This ball has icosahedral symmetry and its own molecular analogue in the form of C60, the famous soccer ball-shaped fullerene. In 2006, a new ball called the TeamGeist was introduced at the World Cup in Germany. This was made of 14 curved panels that together gave it tetrahedral symmetry. This also had a molecular analogue with tetrahedral symmetry among the fullerenes. Now teams at the current World Cup in Brazil are playing with yet another design: the Brazuca, a ball constructed from six panels each with a four-leaf clover shape that knit together like a jigsaw to form a sphere. This has octahedral symmetry. But here's question that has been puzzling chemists, topologists and..errr...soccer fans: is there a molecular analogue of the Brazuca? Or put another way, can fullerenes have octahedral symmetry? Now a pair of mathematicians have finally solved this problem. They've shown that fullerenes can indeed have octahedral symmetry just like the Brazuca, although in addition to hexagonal and pentagonal carbon rings, the ball-shaped molecules must also have rings of 4 and 8 carbon atoms. The next stage is to actually synthesis one of these fullerenes, perhaps something to keep chemists occupied until the 2018 World Cup in Russia."

StartsWithABang writes 55 years ago, the Soviet probe Luna 3 imaged the side of the Moon that faces away from us for the first time. Surprisingly, there were only two very small maria (dark regions) and large amounts of mountainous terrain, in stark contrast to the side that faces us. This remained a mystery for a very long time, even after we developed the giant impact hypothesis to explain the origin of the Moon. But a new study finally appears to solve the mystery, crediting the heat generated on the near side from a hot, young Earth with creating the differences between the two hemispheres.

KentuckyFC writes The idea that light waves can push a physical object is far from new. But a much more recent idea is that a laser beam can also pull objects like a tractor beam. Now a team of Australian physicists has used a similar idea to create a tractor beam with water waves that pulls floating objects rather than pushes them. Their technique is to use an elongated block vibrating on the surface of water to create a train of regular plane waves. When the amplitude of these waves is small, they gradually push the surface of the water along, creating a flow that pushes floating objects with it. However, when the amplitude increases, the waves become non-linear and begin to interact with each other in a complex way. This sets up a flow of water on the surface in the opposite direction to the movement of the waves. The result is that floating objects--ping pong balls in the experiment--are pulled towards the vibrating block, like a tractor beam.

StartsWithABang (3485481) writes "It was one of the most hotly contested questions for decades: we first expected and then found supermassive black holes at the centers of practically all large galaxies. But how did they get there? In particular, you could imagine it happening either way: either there was this top-down scenario, where large-scale structures formed first and fragmented into galaxies, forming black holes at their centers afterwards, or a bottom-up scenario, where small-scale structures dominate at the beginning, and larger ones only form later from the merger of these earlier, little ones. As it turns out, both of these play a role in our Universe, but as far as the question of what came first, black holes or galaxies, only one answer is right."

KentuckyFC writes Stars form when clouds of gas and dust collapse under their own gravity, generating enough heat and pressure to fuse the atoms inside them together. When this cloud of dust and gas is the remnants of a supernova, it can contain all kinds of heavy elements in addition to primordial hydrogen, helium and lithium. Now one astrophysicist has calculated that a recently discovered phenomenon of turbulence, called preferential concentration, can profoundly alter star formation. He points out that turbulence is essentially vortices rotating on many scales of time and space. On certain scales, the inertial forces these eddies create can push heavy particles into the calmer space between the vortices, thereby increasing their concentration. In giant clouds of interstellar gas, this concentrates heavy elements, increasing their gravitational field, attracting more mass and so on. The result is the formation of a star that is made entirely of heavy elements rather than primordial ones. Astrophysicists call the amount of heavy elements in a star its "metallicity". Including preferential concentration in the standard model of star formation leads to the prediction that 1 in 10,000 stars should be totally metal. Now the race is on to find the first of this new class of entirely metal stars.

After some speculation yesterday about the winner of the auction for the first block of bitcoins seized from the Silk Road, the winner went ahead and made his identity public. Tim Draper has won the U.S. Marshals bitcoin auction and is partnering with Vaurum to provide bitcoin liquidity in emerging markets. ... Tim offered this in a statement: “Bitcoin frees people from trying to operate in a modern market economy with weak currencies. With the help of Vaurum and this newly purchased bitcoin, we expect to be able to create new services that can provide liquidity and confidence to markets that have been hamstrung by weak currencies. Of course, no one is totally secure in holding their own country’s currency. We want to enable people to hold and trade bitcoin to secure themselves against weakening currencies.”

theodp (442580) writes "The Internet's Own Boy, the documentary about the life and death of Aaron Swartz, was appropriately released on the net as well as in theaters this weekend, and is getting good reviews from critics and audiences. Which is kind of remarkable, since the Achilles' heel of this documentary, as critic Matt Pais notes in his review, is that "everyone on the other side of this story, from the government officials who advocated for Swartz's prosecution to Swartz's former Reddit colleagues to folks at MIT, declined participation in the film." Still, writer/director Brian Knappenberger manages to deliver a compelling story, combining interesting footage with interviews from Swartz's parents, brothers, girlfriends, and others from his Internet projects/activism who go through the stages of joy, grief, anger, and hope that one sees from loved ones at a wake. "This remains an important David vs. Goliath story," concludes Pais, "of a remarkable brain years ahead of his age with the courage and will to fight Congress-and a system built to impede, rather than encourage, progress and common sense. The Internet's Own Boy will upset you. As it should." And Quinn Norton, who inadvertently gave the film its title ("He was the Internet's own boy," Quinn said after Swartz's death, "and the old world killed him."), offers some words of advice for documentary viewers: "Your ass will be in a seat watching a movie. When it is done, get up, and do something.""

KentuckyFC (1144503) writes The banjo is a stringed instrument that produces a distinctive metallic sound often associated with country, folk and bluegrass music. It is essentially a drum with a long neck. Strings are fixed at the end of the neck, stretched across the drum and fixed on the other side. They are supported by a bridge that sits on the drum membrane. While the instrument is straightforward in design and the metallic timbre easy to reproduce, acoustics experts have long puzzled over exactly how the instrument produces its characteristic tones. Now David Politzer, who won the Nobel prize for physics in 2004, has worked out the answer. He says the noise is the result of two different kinds of vibrations. First there is the vibration of the string, producing a certain note. However, the drum also vibrates and this pushes the bridge back and forth causing the string to stretch and relax. This modulates the frequency of the note. When frequency of this modulation is below about 20 hertz, it creates a warbling effect. Guitar players can do the same thing by pushing a string back and forth after it is plucked. But when the modulating frequency is higher, the ear experiences it as a kind of metallic crash. And it is this that gives the banjo its characteristic twang. If you're in any doubt, try replacing the drum membrane with a piece of wood and the twang goes away. That's because the wood is stiffer and so does not vibrate to the same extent. Interesting what Nobel prize-winning physicists do in their spare time.

KentuckyFC (1144503) writes The idea that people tend to use positive words more often the negative ones is now known as the Pollyanna hypothesis, after a 1913 novel by Eleanor Porter about a girl who tries to find something to be glad about in every situation. But although widely known, attempts to confirm the hypothesis have all been relatively small studies and so have never been thought conclusive.

Now a group of researchers at Computational Story Lab at the University of Vermont have repeated this work on a corpus of 100,000 words from 24 languages representing different cultures around the world. They first measured the frequency of words in each language and then paid native speakers to rate how they felt about each word on a scale ranging from the most negative or sad to the most positive or happy. The results reveal that all the languages show a clear bias towards positive words with Spanish topping the list, followed by Portuguese and then English. Chinese props up the rankings as the least happy. They go on to use these findings as a 'lens' through which to evaluate how the emotional polarity changes in novels in various languages and have set up a website where anybody can explore novels in this way. The finding that human language has universal positive bias could have a significant impact on the relatively new science of sentiment analysis on social media sites such as Twitter. If there is a strong bias towards positive language in the first place, and this changes from one language to another, then that is obviously an important factor to take into account.

KentuckyFC writes: In the early hours of the morning on 24 February 1987, a neutrino detector deep beneath Mont Blanc in northern Italy picked up a sudden burst of neutrinos. Three hours later, neutrino detectors at two other locations picked up a second burst. These turned out to have been produced by the collapse of the core of a star in the Large Magellanic Cloud that orbits our galaxy. And sure enough, some 4.7 hours after this, astronomers noticed the tell-tale brightening of a blue supergiant in that region, as it became a supernova, now known as SN1987a. But why the delay of 7.7 hours from the first burst of neutrinos to the arrival of the photons? Astrophysicists soon realized that since neutrinos rarely interact with ordinary matter, they can escape from the star's core immediately. By contrast, photons have to diffuse through the star, a process that would have delayed them by about 3 hours. That accounts for some of the delay but what of the rest? Now one physicist has the answer: the speed of light through space requires a correction. As a photon travels through space, there is a finite chance that it will form an electron-positron pair. This pair exists for only a brief period of time and then goes on to recombine creating another photon which continues along the same path. This is a well-known process called vacuum polarization. The new idea is that the gravitational potential of the Milky Way must influence the electron-positron pair because they have mass. This changes the energy of the virtual electron-positron pair, which in turn produces a small change in the energy and speed of the photon. And since the analogous effect on neutrinos is negligible, light will travel more slowly than them through a gravitational potential. According to the new calculations which combine quantum electrodynamics with general relativity, the change in speed accounts more or less exactly for the mysterious time difference.

mpicpp (3454017) writes with news that a dump of fare logs from NYC cabs resulted in trip details being leaked thanks to using an MD5 hash on input data with a very small key space and regular format. From the article: City officials released the data in response to a public records request and specifically obscured the drivers' hack license numbers and medallion numbers. ... Presumably, officials used the hashes to preserve the privacy of individual drivers since the records provide a detailed view of their locations and work performance over an extended period of time.

It turns out there's a significant flaw in the approach. Because both the medallion and hack numbers are structured in predictable patterns, it was trivial to run all possible iterations through the same MD5 algorithm and then compare the output to the data contained in the 20GB file. Software developer Vijay Pandurangan did just that, and in less than two hours he had completely de-anonymized all 173 million entries.

KentuckyFC (1144503) writes "One of the goals of neuroscience is to understand how brains process information and generate appropriate behaviour. A technique that is revolutionising this work is optogenetics--the ability to insert genes into neurons that fluoresce when the neuron is active. That works well on the level of single neurons but the density of neurons in a brain is so high that it has been impossible to tell them apart when they fluoresce. Now researchers have solved this problem and proved it by filming the activity in the entire brain of a nematode worm for the first time and making the video available. Their solution comes in two parts. The first is to ensure that the inserted genes only fluoresce in the nuclei of the neurons. This makes it much easier to tell individual neurons in the brain apart. The second is a new techniques that scans the entire volume of the brain at a rate of 80 frames per second, fast enough to register all the neuronal activity within it. The researchers say their new technique should allow bigger brains to be filmed in the near future, opening up the potential to study how various creatures process information and trigger an appropriate response for the first time."

KentuckyFC (1144503) writes Security researchers in Germany have demonstrated an entirely new way to attack computer networks and steal information without anybody knowing. The new medium of attack is ultrasonic sound. It relies on software that uses the built-in speakers on a laptop to broadcast at ultrasonic frequencies while nearby laptops listen out for the transmissions and pass them on, a set up known as a mesh network. The team has tested this kind of attack on a set of Lenovo T400 laptops infected with key-logging software. They say it is possible to transmit ultrasonic signals covertly at data rates of 20 bits per second at distances of up to 20 metres in an office environment. Interestingly, the team created the covert system by adapting a protocol designed for underwater acoustic communication. They've also tested various strategies for defeating this kind of attack. An obvious option is to disable all speakers and microphones but this also prevents ordinary activities such as VOIP communication. Instead, they suggest filtering the audio signals to prevent ultrasonic transmissions or converting them into an audible frequency. This may be newer than most attack vectors, but it's not the first time that ultrasonic transmission has been demonstrated as a vulnerability; in November of last year we mentioned malware operating along the same lines, as investigated byPwn2Own creator Dragos Ruiu.

New submitter InternetOfJim writes: "This is one of the most fun weekend projects I've done in a while — a fitness tracker for my elliptical trainer. But the real agenda was to figure out how lazy I could be via web services (Keen IO and Brace IO) and development platforms (Electric Imp). Quite lazy, as it turns out. I wound up with a working device and a nice realtime dashboard with no soldering, no backend to manage, and surprisingly little original code needed beyond the sensing and power conserving parts of the firmware and a little javascript to customize the dashboard."

KentuckyFC (1144503) writes 'One curious feature on the Moon's surface are "lunar swirls", wisp-like regions that are whiter than surrounding areas and that, until recently, astronomers could not explain. But one team of physicists recently showed that these areas are protected by weak magnetic fields that deflect high energy particles from the Sun and so prevent the darkening effect this radiation has. The problem they had to solve was how a weak field could offer so much protection, when numerous studies of long duration spaceflight have shown that only very powerful fields can act like radiation shields. The team now says that these previous studies have failed to take into account an important factor: the low density plasma that exists in space. It turns out that this plasma is swept up by a weak magnetic field moving through space, creating a layer of higher density plasma. That's important because the separation of charge within this layer creates an electric field. And it is this field that deflects the high energy particles from the Sun. That explains the lunar swirls but it also suggests that the same effect could be exploited to protect astronauts on long duration missions to the moon, to nearby asteroids and beyond. This team has now produced the first study of such a shield and how it might work. Their shield would use superconducting coils to create a relatively weak field only when it is needed, during solar storms, for example. And it would create a plasma by pumping xenon into the vacuum around the vehicle, where it would be ionised by UV light. The entire device would weigh around 1.5 tonnes and use about 20 KW of power. That's probably more than mission planners could currently accommodate but it is significantly less than the science fiction-type power requirements of previous designs. And who knows what other tricks of plasma physics engineers might be able to exploit to refine this design. All of a sudden, long duration space flight looks a little more feasible.'

KentuckyFC writes: 'In 1978, the American researcher Michael Hart published The 100: A Ranking of the Most Influential Persons in History, a book that became an international best seller. Since then, various others have published similar lists. But all suffer the same drawback: they are subjective list ultimately influenced by numerous cultural factors. Now data scientists have come up with a way to extract an objective list of the 100 most influential people in history using the network of links between biographical articles on Wikipedia and how they vary between 24 different language editions, including English, Chinese, Russian Arabic and so on. The researchers assume that people who are highly ranked in different language editions are influential across both language cultures and that the more appearances they make in different language editions, the more influential they are. But the actual ranking is done by PageRank-like algorithms that consider a biographical article important if it is pointed to by other important articles.

The resulting lists of the most influential men and women might surprise. The top PageRanked individual is Carl Linnaeus, the 18th century Swedish botanist who developed the modern naming scheme for plants and animals, followed by Jesus. The top PageRanked women are: Elizabeth II followed by Mary (mother of Jesus). For comparison, just under half of the top 100 most influential also appear in Hart's 1978 book. But this is just the beginning. By counting the individuals from one culture that influence other cultures, the team is able to work out which cultures have dominated others. And by looking only at people born before certain dates, they can see how the influence of different cultures has waxed and waned throughout 35 centuries of recorded history.'

KentuckyFC (1144503) writes 'Back in 2012, astronomers constructed an array of 256 radio antennas in the high deserts of New Mexico designed to listen for radio waves produced by gamma ray bursts, one of the most energetic phenomena in universe and thought to be associated with the collapse of a rapidly rotating stars to form neutron stars and black holes. The array generates all sky images of signals produced in the 25 MHz to 75 MHz region of the spectrum. But when researchers switched it on, they began to observe puzzling streaks across the sky that couldn't possibly be generated by gamma ray bursts. One source left a trail covering more than 90 degrees of the sky in less than 10 seconds. This trail then slowly receded to an endpoint which glowed for around 90 seconds. Now the first study of these transient radio signals has discovered that they are almost certainly produced by fireballs as they burn up after entering the Earth's atmosphere. The conclusion comes after the researchers were able to match several of the radio images with visible light images of fireballs gathered by NASA's All Sky Fireball Network. That solves the mystery but not without introducing another to keep astrophysicists busy in future. The question they're scratching their heads over now is how the plasma trails left by meteors can emit radio waves at this frequency.'

StartsWithABang (3485481) writes 'Earlier this week, attempts to cut NASA's budget were defeated, and it looks like the largest space agency in the world will actually be getting nearly a 2% budget increase overall. While common news outlets are touting this as a great budget victory, the reality is that this is shaping up to be just another year of pathetic funding levels, putting our greatest dreams of exploring and understanding the Universe on hold. A sobering read for anyone who hasn't realized what we could be doing.'

KentuckyFC (1144503) writes "Since the 1960s, geophysicists have known that some earthquakes are preceded by ultra-low frequency magnetic pulses that increase in number until the quake takes place. But this process has always puzzled them: how can rocks produce magnetic pulses? Now a group of researchers has worked out what's going on. They say that rocks under pressure can become semiconductors that produce magnetic pulses under certain circumstances.

When igneous rocks form in the presence of water, they contain peroxy bonds with OH groups. Under great temperature and pressure, these bonds break down creating electron-holes pairs. The electrons become trapped at the site of the broken bonds but the holes are free to move through the crystal structure. The natural diffusion of these holes through the rock creates p and n regions just like those in doped semiconductors. And the boundary between these regions behaves like the p-n junction in a diode, allowing current to flow in one direction but not the other. At least not until the potential difference reaches a certain value when the boundary breaks down allowing a sudden increase in current. It is this sudden increase that generates a magnetic field. And the sheer scale of this process over a volume of hundreds of cubic meters ensures that these magnetic pulses have an extremely low frequency that can be detected on the surface. The new theory points to the possibility of predicting imminent earthquakes by triangulating the position of rocks under pressure by searching for the magnetic pulses they produce (although significantly more work needs to be done to characterize the process before then)."

StartsWithABang writes: "If everything began with the Big Bang — from a hot, dense, expanding state — and things have been cooling, spreading out, but slowing down ever since, you might think that means that given enough time (and a powerful enough space ship), we'll eventually be able to reach any other galaxy. But thanks to dark energy, not only is that not the case at all, but most of the galaxies in our Universe are already completely unreachable by us, with more leaving our potential reach all the time. Fascinating, terrifying stuff."

StartsWithABang (3485481) writes "It's hard to believe, but there are people alive today who remember a world where Newtonian gravity was the accepted theory of gravitation governing our Universe. 95 years ago today, the 1919 solar eclipse provided the data that would provide the test of the three key options for how light would respond to the presence of a gravitational field: would it not bend at all? Would it bend according to Newton's predictions if you took the "mass" of a photon to be E/c^2? Or would it bend according to the predictions of Einstein's wacky new idea? Celebrate the 95th anniversary of relativity's confirmation by reliving the story."

KentuckyFC (1144503) writes "The history of astronomy is littered with ideas that once seemed incontrovertibly right and yet later proved to be bizarrely wrong. Not least among these are the ancient ideas that the Earth is flat and at the center of the universe. But there is no shortage of others from the modern era. Now one astronomer has compiled a list of examples of wrong-thinking that have significantly held back progress in astronomy. These include the idea put forward in 1909 that telescopes had reached optimal size and that little would be gained by making them any bigger. Then there was the NASA committee that concluded that an orbiting x-ray telescope would be of little value. This delayed the eventual launch of the first x-ray telescope by half a decade, which went on to discover the first black hole candidate among other things. And perhaps most spectacularly wrong was the idea that other solar systems must be like our own, with Jupiter-like planets orbiting at vast distances from their parent stars. This view probably delayed the discovery of the first exoplanet by 30 years. Indeed, when astronomers did find the first exo-Jupiter, the community failed to recognize it as a planet for six years. As Mark Twain once put it: 'It ain't what you don't know that gets you into trouble. It's what you know for sure that just ain't so.'"

An anonymous reader writes "'Save your work!' — This was a rallying cry for an entire generation of workers and students. The frequency and unpredictability of software crashes, power outages, and hardware failures made it imperative to constantly hit that save button. But in 2014? Not so much. My documents are automatically saved (with versioning) every time I make a change. My IDE commits code changes automatically. Many webforms will save drafts of whatever data I'm entering. Heck, even the games I play have an autosave feature. It's an interesting change — the young generation will grow up with an implicit trust that whatever they type into a computer will stay there. Maybe this is my generation's version of: 'In my day, we had to get up and walk across the room to change the channel on the TV!' In any case, it has some subtle but interesting effects on how people write, play, and create. No longer do we have to have constant interruptions to worry about whether our changes are saved — but at the same time, we don't have that pause to take a moment and reflect on what we've written. I'm sure we've all had moments where our hands hover over a save/submit button before changing our minds and hammering the backspace key. Maybe now we'll have to think before we write."

StartsWithABang (3485481) writes "Even with the add-ons of dark matter, dark energy and inflation, the Big Bang still thrives as the most successful scientific model of the Universe ever constructed. It not only accounting for phenomena like the abundance of the light elements, the cosmic microwave background, and the Universe's large-scale structure, but it's led to observable predictions about their details that have since been verified. But there's one thing the Big Bang has generically predicted that we haven't been able to test: a cosmic background of low-energy, relic neutrinos."

StartsWithABang writes: "Here on Earth, we think of shooting stars and meteor showers as things that happen periodically; sometimes they're spectacular, sometimes they're rare. But in all cases, they're caused by comet debris, and they should flare up each time the Earth crosses the comet's path. But as it turns out, every meteor shower had a point in its past where it happened for the very first time. In all of human history, we've never recorded one that occurred for the very first time where none happened before. Well, for those of you who want to take the chance to be a part of it, this coming Friday night/Saturday morning, look for the Camelopardalids, making their Earthly debut this year!"

KentuckyFC (1144503) writes "The study of proteins has become one of the hottest topics in science in the last 20 years, and not just for biologists. Researchers have been measuring the electrical properties of proteins for some time, discovering that some of them act like switches in certain circumstances. That's potentially useful but without a robust theoretical model of how these properties arise, nobody has been able to incorporate proteins into real devices. Now electronics engineers have developed the first model that reliably describes the real electrical behaviour of proteins and how it changes when they bond to other molecules. It even predicts the behaviour in new situations. That should make it possible to use proteins in the same way as other electronic components such as transistors, diodes and so on. That's leading to an entirely new field of science called proteotronics in which proteins work seamlessly with other components in electronic devices. First up, an electronic nose based on the olfactory receptor OR-17, a protein found in rats, which behaves like an electronic switch when it detects the presence of aldehydes such as octanal."

KentuckyFC writes: "In behavioral psychology, the theory of operant conditioning is the notion that an individual's future behavior is determined by the punishments and rewards he or she has received in the past. It means that specific patterns of behavior can be induced by punishing unwanted actions while rewarding others. While the theory is more than 80 years old, it is hard at work in the 21st century in the form of up- and down-votes — or likes and dislikes — on social networks. But does this form of reward and punishment actually deter unwanted actions while encouraging good behavior? Now a new study of the way voting influences online behavior has revealed the answer. The conclusion: negative feedback leads to behavioral changes that are hugely detrimental to the community. Not only do authors of negatively-evaluated content contribute more but their future posts are of lower quality and are perceived by the community as such. What's more, these authors are more likely to evaluate fellow users negatively in future, creating a vicious circle of negative feedback. By contrast, positive feedback does not influence authors much at all. That's exactly the opposite of what operant conditioning theory predicts. The researchers have a better suggestion for social networks: 'Given that users who receive no feedback post less frequently, a potentially effective strategy could be to ignore undesired behavior and provide no feedback at all.' Would Slashdotters agree?"

StartsWithABang (3485481) writes "You've all had the experience: you're all excited to microwave your favorite snack. So you pull it out of the freezer, you throw it in, and you let it rip. A minute or two later, you pull it out, and there it is: boiling on the outside, frozen in the middle. Finally, a physicist answers the eternal question: why do microwaved foods remain frozen on the inside when they reach scalding temperatures on the outskirts? Starts With A Bang explains the whole phenomenon. Bonus for the crisping sleeve explanation!"

KentuckyFC (1144503) writes "One of the most widely shared tweets in history is Obama's "Four more years", posted after his second presidential election victory and currently retweeted 775,000 times. But how would different wording have influenced this tweet's popularity and the way it spread? It's easy to imagine that there's no way of telling what might have been in such an alternative universe. But a surprising phenomenon on Twitter has allowed data scientists to study this kind of alternative reality and work out the factors that make one tweet more popular than another. It turns out that the twitter stream contains a surprisingly large number of tweets from the same authors, pointing to the same content but with different messages. That's a natural experiment in which factors such as the author, the URL, the number of followers and so on are all held constant while the message varies. By studying these pairs of tweets, researchers can measure how well each performs and then determine which factors contribute to their popularity. These turn out to be things like the amount of information the tweet contains, the language it uses and even whether it includes a request for a retweet. The team has developed an algorithm that predicts which of a pair of tweets is more likely to be successful with greater accuracy than humans. And they've even set up a website where anybody can test their tweet-rating ability and thereby improve their chances of writing the perfect tweet."

KentuckyFC (1144503) writes "There is growing evidence that the center of the Milky Way contains a mysterious object some 4 million times more massive than the Sun. Many astronomers believe that this object, called Sagittarius A*, is a supermassive black hole that was crucial in the galaxy's birth and formation. The thinking is that about 100 million years after the Big Bang, this supermassive object attracted the gas and dust that eventually became the Milky Way. But there is a problem with this theory--100 million years is not long enough for a black hole to grow so big. The alternative explanation is that Sagittarius A* is a wormhole that connects the Milky Way to another region of the universe or even a another multiverse. Cosmologists have long known that wormholes could have formed in the instants after the Big Bang and that these objects would have been preserved during inflation to appear today as supermassive objects hidden behind an event horizon, like black holes. It's easy to imagine that it would be impossible to tell these objects apart. But astronomers have now worked out that wormholes are smaller than black holes and so bend light from an object orbiting close to them, such as a plasma cloud, in a unique way that reveals their presence. They've even simulated what such a wormhole will look like. No telescope is yet capable of resolving images like these but that is set to change too. An infrared instrument called GRAVITY is currently being prepared for the Very Large Telescope Interferometer in Chile and should be in a position to spot the signature of a wormhole, if it is there, in the next few years."

First time accepted submitter Cornelie Roe (3627609) writes in with some bad news about the population of Japan. "The number of children in Japan has fallen to a new low, while the amount of people over 65 has reached a record high as the population ages and shrinks, the government said. There were an estimated 16.33 million children aged under 15 as of 1 April, down 160,000 from a year earlier, the internal affairs and communications ministry said on Sunday. It was the 33rd straight annual decline and the lowest level since records began in 1950. Children accounted for 12.8% of the population, the ministry said. By contrast, the ratio of people aged 65 or older was at a record high, making up 25.6% of the population. Jiji Press said that, of countries with a population of at least 40 million, Japan had the lowest ratio of children to the total population – compared with 19.5% for the United States and 16.4% for China. Last month, the government said the number of people in the world's third largest economy dropped by 0.17% to 127,298,000 as of 1 October 2013. This includes long-staying foreigners. The proportion of people aged 65 or over is forecast to reach nearly 40% in 2060, the government has warned."

KentuckyFC writes: "Random numbers are the lifeblood of many cryptographic systems and demand for them will only increase in the coming years as techniques such as quantum cryptography become mainstream. But generating genuinely random numbers is a tricky business, not least because it cannot be done with a deterministic process such as a computer program. Now physicists have worked out how to use a smartphone camera to generate random numbers using quantum uncertainties. The approach is based on the fact that the emission of a photon is a quantum process that is always random. So in a given unit of time, a light emitter will produce a number of photons that varies by a random amount. Counting the number of photons gives a straightforward way of generating random numbers. The team points out that the pixels in smartphone cameras are now so sensitive that they can pick up this kind of quantum variation. And since a camera has many pixels working in parallel, a single image can generate large quantities of random digits. The team demonstrates the technique in a proof-of principle experiment using the 8-megapixel camera on a Nokia N9 smartphone while taking images of a green LED. The result is a quantum random number generator capable of producing digits at the rate of 1 megabit per second. That's more than enough for most applications and raises the prospect of credit card transactions and encrypted voice calls from an ordinary smartphone that are secured by the laws of quantum physics."