Earth Has a Ring of Anti-Protons !

While it's not as visually cool as what Saturn has going for it, this is still an important development, even if we can't technically "see" the ring with our primitive Earthling eyes.

According to New Scientist, this anti-proton ring joins the previously discovered positron cloud that's also circling the Earth like an invisible shield. Ironically, the anti-protons are 2,000 times more massive than their positron counterparts, but were discovered second. Both are trapped in a donut-like ring called the Van Allen radiation belt that's held in place by the planet's magnetic field.

In the distant future, a spacecraft designed to use anti-protons (or other types of antimatter) as a fuel source could tap into this ring to top off its tanks and head out into the void, said Alessandro Bruno, a member of the University of Rome Tor Vergata team that confirmed the anti-proton area's existence.

Between July 2006 and December 2008, PAMELA detected 28 antiprotons trapped in spiralling orbits around the magnetic field lines sprouting from the Earth’s south pole (Astrophysical Journal Letters, DOI: 10.1088/2041-8205/737/2/l29). PAMELA samples only a small part of the inner radiation belt, but antiprotons are probably trapped throughout it. “We are talking about of billions of particles,” says team member Francesco Cafagna from the University of Bari in Italy.

Twenty-eight antiprotons sounds like nothing, really. But that’s actually a pretty substantial quantity, and verifies the hypothesized but not-yet-evident theory that such a ring might exist. So it looks like now all we need are those super-efficient rockets.


Source:New Scientist [image: New Scientist]

Time Travel Impossible ?

Shengwang Du and His Team Measured the Speed of a Photon

Hong Kong scientists claim to have proved that a single photon cannot travel faster than the speed of light in a vacuum, making time travel seemingly impossible.

These findings are consistent with Einstein’s claim that the speed of light is the “traffic law of the universe” or, otherwise put, that nothing can travel faster than light. Of course, humanity’s dream of time travel has long relied on the hope that Einstein was wrong. We got a glimmer of hopeback in 1999 when scientists found superluminal (faster-than-light) propagation of optical pulses in some specific medium, the team said. Unfortunately, this was later revealed to be a visual effect, and the photons involved couldn’t actually transmit information.

Since then, there has been a debate surrounding whether or not a single photon might actually be able to travel faster than the speed of light. This experiment, conducted by a team at the Hong Kong University of Science and Technology and led by Professor Shengwang Du, measured the ultimate speed of a photon using controllable waveforms. An explanation, from the press release:

"HKUST's team used a demonstration which required not only producing single photons, but separating the optical precursor, which is the wave-like propagation at the front of an optical pulse, from the rest of the photon wave packet. To do so, Prof Du's team generated a pair of photons, and then passed one of them through a group of laser-cooled rubidium atoms with an effect called electromagnetically induced transparency (EIT). For the first time, they successfully observed optical precursors of a single photon.

The team found that, as the fastest part of a single photon, the precursor wave front always travels at the speed of light in vacuum. The main wave packet of the single photon travels no faster than the speed of light in vacuum in any dispersive medium, and can be delayed up to 500 nanoseconds in a slow light medium. Even in a superluminal medium where the group velocity (of an optical pulse peak) is faster than the speed of light in vacuum, the main part of the single photon has no possibility to travel faster than its precursor."

What that means for us: probably no time travel. Du says their results "confirm the upper bound on how fast information travels with light. By showing that single photons cannot travel faster than the speed of light, our results bring a closure to the debate on the true speed of information carried by a single photon." That indicates, in turn, that time travel is not possible, and that decades of beloved science fiction may not be entirely based on fact.

Source: Popsci via Daily Mail, Hong Kong University of Science and Technology

Physicists Confirm Existence of New Particle

Physicists working at Fermilab’s particle accelerator have confirmed the observation of an entirely new particle — the the Xi-sub-b baryon.


Baryons are particles formed of three quarks, in different configurations. The proton is a baryon that consists of two up and one down quark, and the neutron is two down and one up. The Xi-sub-b has an up quark, a strange quark (yes, that’s its real name) and a heavy bottom quark (again, real name), meaning that it weighs around six times as much as a proton or neutron.

Its existence has been predicted for some time, but hadn’t previously been observed. It doesn’t stick around long, though — traveling a fraction of a millimeter before decaying into lighter particles.

Happily, Fermilab has smashed together almost 500 trillion sets of particles, so researchers were able to verify the particle’s existence multiple times over. The Xi-sub-b has been spotted 25 times.

Fermilab’s Tevatron, where the Xi-sub-b was discovered, is based in Illinois in the United States, and was the highest-energy particle accelerator in the world until the Large Hadron Collider opened below Geneva.

Source: Wired

Quantum internet Coming Soon !

Is this the beginning of the quantum Internet? Researchers have shown that quantum and classical data streams can be interwoven within traditional fiber optics networks, enabling the distribution of quantum information to the home on existing cable. That means quantum key distribution (QKD) can work alongside traditional, classical data channels, a development that essentially lays the groundwork for a quantum Internet that exists alongside the classical one we have now.

The team, from the Tyndall National Institute at University College Cork in Ireland, has demonstrated in a new paper how qubits--the basic blocks of quantum computing--can travel over standard fiber optics networks. This has been shown before, but not in a real-world kind of way. In other words, you can move qubits over fiber optics in theory, sure. But to feasibly do so--especially alongside traditional data streams--is a huge step forward.

The problem has always been one of interference. Qubits are carried by single photons, while traditional data packets are carried by strong laser pulses. Those pulses flying throughout a network result in spontaneous Raman scattering of photons within the optical fiber, and that in turn interferes with the quantum channels, causing a rate of error that’s high enough to be prohibitive.

So the Cork team figured out how to squeeze the qubits in there in between the Raman scattering. When the pulses of laser light are moving through the optical fiber, the interference pulses along with it--that is, there are quiet moments in between bursts of Raman scattering that lead to interference or crosstalk on the network. By carefully controlling the timing and wavelength of the quantum data, the researchers showed that they could slip quantum data generated by a QKD scheme in between the noise areas, where they can travel untouched by the interference.

All that is key if we’re ever going to practically begin a shift over to widespread quantum computing (first we’ll need some good quantum computers of course, but it never hurts to be prepared). It would be really expensive to build a second quantum network alongside our existing classical data networks. Using this scheme, it appears you could get classical and quantum streams running alongside each another, making quantum IT more commercially viable.

Source: Popsci via PhysOrg

'Sensing skin' could detect cracks in concrete structures

Concrete may be one of the toughest buildings materials in common use but it does develop cracks over time, and in the case of structures such as buildings or bridges, it is imperative that those cracks are noticed before they lead to a collapse. While visual inspections are useful, they are also time-consuming, and may miss tiny but structurally-significant cracks. Some technologies have been developed to automate the process, such as rust sensors for steel-reinforced concrete. Now, an international team of scientists is proposing a system of flexible crack-detecting skins, that could be applied to the surfaces of concrete surfaces.

The "sensing skin" was developed by civil engineers at the Massachusetts Institute of Technology (MIT), working with physicists at Germany's University of Potsdam.

Structures such as bridges would simply have pieces of the skin glued onto any areas where cracks were considered likely to occur. The skin would contain patterns of capacitive rectangular patches, arranged in different patterns within the skin, depending on the type of stress that was likely - patches oriented diagonally to one another would work best for detecting cracks caused by shear, whereas horizontally-joined patches would be better for detecting sag in horizontal beams, for instance.

The capacitance of each patch (the amount of energy it was storing) would be altered by any movement underneath it, as would be caused by the formation of cracks. Once a day, a computer that was attached to the skin would send an electrical current through it, measuring the capacitance of each patch. If sharp differences were noted between adjacent patches, the computer would note the exact location, and then notify a human inspector of the discrepancy. This ability to pinpoint the location reportedly sets the system apart from other stress-detecting technologies, that don't provide such specific coordinates.

So far, the largest piece of the skin tested in laboratory conditions has measured 8 by 4 inches (20 by 10 cm). While a stretchy silicon fabric with silver electrodes was used initially, it proved to be too thin and flexible for some applications. It has since been replaced with a thermoplastic elastomer mixed with titanium dioxide, with the capacitive patches made from painted-on black carbon.

Source: Gizmag

China Opens the World's Longest Bridge Over Water, Toppling American Record-Holder

Along with its massive high-speed rail network, China has officially surpassed the United States in yet another piece of transportation infrastructure: the world’s longest sea bridge.

The new bridge spans Jiaozhou Bay, on the southern coast of China’s Shandong Peninsula in northeastern China. At 26.4 miles long, it beats Louisiana’s Lake Pontchartrain Causeway — the previous world-record holder — by at least 2 miles, according to the Guinness Book of World Records.

Chinese workers toiled at marathon pace to build the bridge in four years, starting at each side and meeting in the middle. The structure has 5,200 pillars and cost at least $2.3 billion, according to Chinese state-run media.

The Guinness officials say the bridge is earthquake- and typhoon-proof, and designed to withstand the impact of a 300,000-ton vessel. It links the port city of Qingdao to the island of Huangdao, cutting drive time from 40 to 20 minutes, according to the state-run China Daily.

The New Orleans Times-Picayune reports that Americans are apparently not giving up the world’s longest title without a fight, however. The newspaper talked to Carlton Dufrechou, general manager of the Lake Pontchartrain Causeway, who pointed out that the Jiaozhou bridge has a bend in it, and that the over-water length is only 16 miles, compared to 24 for his bridge.

“Bunch of wannabes,” he said. Read the Times-Pic’s piece for his full take, in which he calls the Chinese news “propaganda.”

In any case, the bridge looks pretty neat, especially set to this haunting soundtrack. Check out some aerial views below.

Source: Popsci via via IB Times

New Alloy Can Convert Heat Directly Into Electricity

A new alloy with unique properties can convert heat directly into electricity, according to researchers at the University of Minnesota. The alloy, a multiferroic composite of nickel, cobalt, manganese and tin, can be either non-magnetic and highly magnetic, depending on its temperature.

Multiferroic materials possess both magnetism and ferroelectricity, or a permanent electric polarization. Materials with both of these properties are very rare; check out this explainer from the National Institute of Standards and Technology if you’re interested in the electron orbital arrangements that cause these phenomena.

In this case, the new alloy — Ni45Co5Mn40Sn10 — undergoes a reversible phase transformation, in which one type of solid turns into another type of solid when the temperature changes, according to a news release from the University of Minnesota. Specifically, the alloy goes from being non-magnetic to highly magnetized. The temperature only needs to be raised a small amount for this to happen.

When the warmed alloy is placed near a permanent magnet, like a rare-earth magnet, the alloy’s magnetic force increases suddenly and dramatically. This produces a current in a surrounding coil, according to the researchers, led by aerospace engineering professor Richard James. Watch a piece of the alloy leap over to a permanent magnet in the video clip below.

A process called hysteresis causes some of the heat energy to be lost, but this new alloy has a low hysteresis, the researchers say. Because of this, it could be used to convert waste heat energy into large amounts of electricity.

One obvious use for this material would be in the exhaust pipes of vehicles. Several automakers are already working on heat transfer devices that can convert a car’s hot exhaust into usable electricity; General Motors is using alloys called skutterudites, which are cobalt-arsenide materials doped with rare earths.

Rare earth magnets are already a necessity in many hybrid car batteries, so heat-capture devices made of the new multiferroic compound could be placed near the magnets.

The material could also be used in power plants or even ocean thermal energy generators, the researchers said.

A paper on the alloy was published in the journal Advanced Energy Materials.

Source: Eurekalert

First Graphene-Based Integrated Circuit Smaller than a Grain of Salt

IBM researchers have built the first integrated circuit based on graphene, a breakthrough the company says could herald a future based on graphene wafers instead of silicon. The circuit, a 10 gigahertz frequency mixer, could give wireless devices greater range. At higher frequencies, the technology could someday allow law enforcement and medical personnel to see inside objects or people without the harmful effects of X-rays, according to IBM.



It's yet another advancement in the use of graphene—which, in case you forgot, is that fantastic, ultra-thin "wonder material" that won two scientists the Nobel prize for physics. Graphene is only one layer of (carbon) atoms thick—but despite its ultra-lightness, it's still nearly indestructible. Like, 200x stronger than steel and the strongest substance in the known universe kind of indestructible. But it's also flexible and its conductivity is 100x greater than silicon. So it's badass.


The circuit is a broadband radio-frequency mixer, which, as IEEE Spectrum explains, is a crucial component of radios. It creates new radio signals by finding the sum and difference between two input frequencies. IBM’s circuit performed frequency mixing up to 10 GHz, and worked well up to 257 degrees F. The research team believes it can get even faster — if so, chips like these could improve cell phone and transceiver signals, possibly allowing phones to work in spots where they currently can’t receive service, the company says.


Several teams have been working on graphene transistors and receivers, but it has been difficult to marry the single-carbon-atom sheets to the metals and alloys used on chips. This circuit also uses aluminum, gold and palladium, for instance, which do not adhere well to graphene. What’s more, graphene can be easily damaged in the etching process, as Yu-Ming Lin and colleagues at IBM’s Thomas J. Watson Research Center explain in a paper about the new circuit.


The team figured out a new process that clears those hurdles by growing graphene on the silicon face of the silicon-carbide wafer. Then they coated the graphene in a polymer, conducted the necessary etching, and removed the polymer using some acetone. The transistor gates are only 550 nanometers long, and the entire wafer is the size of a grain of salt, IBM says.


Pretty soon, we could be seeing applications of graphene in high-bandwidth communication and low-cost smart phone and TV displays. 


Compared to silicon, the graphene transistor could be less expensive, use less energy and significantly free up room in portable electronics and smart phones.

The research is reported in today’s issue of the journal Science.


Source: Popsci Via Gizmodo

World record 26 terabits per second data transmission achieved

With video content consuming ever more bandwidth, the need for faster data transmission rates has never been greater. Now a team of scientists at Germany's Karlsruhe Institute of Technology (KIT) are claiming a world record in data transmission with the successful encoding of data at a rate of 26 terabits per second on a single laser beam and transmitting it over a distance of 50 km (31 miles). The scientists claim this is the largest data volume ever transported on a laser beam and enables the transmission of 700 DVD's worth of content in just one second.

With no electronic processing methods available for a data rate of 26 terabits per second, the team developed a new opto-electric data decoding process. This process relies on purely optical calculations to break down the initial high data rate into smaller bit rates that can then be processed electrically. The record-breaking data encoding also employed the orthogonal frequency division multiplexing(OFDM) scheme based on Fast Fourier Transformation (FFT) mathematical routines that is commonly used in mobile communications networks including digital TV and audio broadcasts.

Because energy is required for the laser and a few process steps only, the team says the new method is not only extremely fast, but also very energy efficient.

"Our result shows that physical limits are not yet exceeded even at extremely high data rates," says Professor Jürg Leuthold, who led the KIT experiment. "A few years ago, data rates of 26 terabits per second were deemed utopian even for systems with many lasers and there would not have been any applications. With 26 terabits per second, it would have been possible to transmit up to 400 million telephone calls at the same time. Nobody needed this at that time. Today, the situation is different."

The latest breakthrough follows on from the previous high-speed data transmission record set by the KIT scientists in 2010, when they successfully exceeded the data rate of 10 terabits (or 10,000 billion bits) per second.

The KIT experiment involved companies and scientists from all over Europe, including members of the staff of Agilent and Micram Deutschland, Time-Bandwidth Switzerland, Finisar Israel, and the University of Southampton in Great Britain. The experiment is detailed in the journal Nature Photonics.

Source: Gizmag

DNA-Based Computing Could Replace Silicon !

 

DNA is the future of computing,” Jian-Jun Shu tells PhysOrg. And why not? Silicon is slow by comparison, computes in a binary system, creates waste heat, and is not particularly easy on the environment. DNA-based computing can perform better than silicon in several respects, Shu says, and he and a few of his students at Nanyang Technical University in Singapore have set out to prove it.

The general idea: the human body performs computations all of the time, and does so far faster than even the fastest silicon-based supercomputer. Moreover, it does so in a parallel fashion, working with more breadth, speed, and agility than the ones and zeros of silicon computation. For massive parallel problems, artificial intelligence problems, and combinatorial problems, DNA-based computing could be far more efficient.

How does it work? Shu and company are just starting to scratch the surface of what DNA computing could do, he admits, but in the lab he and his students have manipulated strands of DNA to do all kinds of things. They have fused strands together, broken them apart, snipped them, and otherwise affected them to a certain goal or end like storing information in DNA molecules that can be later retrieved for computational purposes.

The operations right now are simple: addition or subtraction mainly, nothing as complex as what silicon computers can do on their worst days. The potential for that equation to be flipped is there, but first there are several obstacles that need to be overcome. For one, there is no real interface for DNA-based computing through which humans can interact with and display data. There also exists no equivalent to the CPU--something that can facilitate these complex operations without human interference.

But that will change, Shu says, with increases in technology and more time in the lab. Just don’t expect to be computing with nucleotides anytime in the near term.

Source: PopSci Via PhysOrg

Solar plane's first international flight a success

Solar Impulse during flight tests earlier this year / Image: Solar Impulse

Solar Impulse has successfully completed its first international flight. After spending most of last week on standby waiting for favorable weather conditions, the Swiss solar powered aircraft made the run from Payerne to Brussels on Friday May 13 in a flight that lasted 12 hours 59 minutes. Hats-off to the Solar Impulse team!

Solar Impulse is an astonishing feat of engineering. It has a wingspan of over 200 feet (61 m) yet it weighs only 1600 kg (3,527 lb) and carries almost 12,000 solar cells which supply all of the energy required to keep it aloft.

The plane has actually flown for a longer duration than Friday's 12 hours 59 minute flight, setting a mark of more than 26 hours in an overnight flight last summer. The achievement of its first international flight is as much about the logistics of civil aviation as it is about performance. Solar Impulse is a slow moving aircraft – during the latest flight it flew at around 31 mph (50 km/h) – and this makes for some unique challenges when it comes to flight planning as Solar Impulse Air Traffic Control manager Niklaus Gerber explains on the Solar Impulse Blog:

"HB-SIA is an obstacle for civil and military aviation because it is not very mobile, and rather inflexible. It is slow (31 mph/50 km/h) and does not really show up on radar (you see it as a point that hardly moves). Now, alongside it, there are aircraft that are traveling at between 400 and 900 km/h. So the other aircraft are the ones that have to make adjustments to avoid it. But this scenario is theoretical because we have done everything to avoid it in planning the flight. Usually, the separation distance between aircraft is 300 meters (984 ft) vertically and 8 kilometers (5 miles) when flying at the same height. In the case of Solar Impulse, our margin of safety is much greater. And an aircraft that passes above it needs to be at least 900 meters (2,953 ft) higher, due to the turbulence it creates which descends for about 5 minutes at a rate of 150 meters (492 ft) per minute before dissipating."

Successfully negotiating these constraints in the flight from Switzerland to Belgium is therefore a big milestone in the build up towards the planned round-the-world journey.

A new future for aviation?

The project founded by Bertrand Piccard and André Borschberg (who was at the controls during the first international flight) is not geared towards producing a commercial product but instead aims to demonstrate just how much can be achieved with renewable technology. Even without the round the world trip that the team plans to undertake in 2013, it's arguable that the achievements of the past year which began with the aircraft's maiden flight in April 2010 have already gone a long way to proving the point. We could well be looking back on this period as a "Wright brothers moment" in the history of aviation.

In the flight from Payerne to Brussels, Solar Impulse covered around 390 miles (628 km) using no fuel. A rough calculation tells us that a Boeing 747 would have used around 2,000 gallons (7,570 L) of fuel to make the same trip.* Of course it's not much of a comparison when you consider that a commercial airliner can carry hundreds of people, but one can't help but think that the seeds of a new era are being sewn. Solar Impulse is powered by 4 x 10 horsepower electric engines, the Wright Brothers had 12 horsepower at their disposal when they flew at Kitty Hawk in 1903. Food for thought.

Watch the majestic landing at Brussels in the Solar Impulse video below:

* A 747-400 that flies 3,500 statute miles (5,630 km) and carries 126,000 pounds (56,700 kg) of fuel will consume an average of five gallons (19 L) per mile (Boeing.com).

Thin-film flexible 'Paperphone' created

Researchers from the Human Media Lab at Canada's Queen's University have created a fully-functioning floppy E-Ink smartphone, which they also refer to as a paper computer. Like its thicker, rigid-bodied counterparts, the Paperphone can do things like making and receiving calls, storing e-books, and playing music. Unlike them, however, it conforms to the shape of its user's pocket or purse, and can even be operated through bending actions.

"This computer looks, feels and operates like a small sheet of interactive paper," said its creator, Roel Vertegaal, who is also the director of the Human Media Lab. "You interact with it by bending it into a cell phone, flipping the corner to turn pages, or writing on it with a pen."

The device has a 9.5-cm (3.74-inch) thin film flexible E-Ink display, underneath which is a flexible printed circuit incorporating resistive bend sensors. Those sensors allow it to be programmed to recognize different types of bending gestures, which will subsequently result in it doing things such as navigating menus, making calls, selecting songs, or any other function. A built-in Wacom tablet also allows users to draw on its screen – making it even more paper-like.

When not actually being operated, the Paperphone consumes no electricity. Vertegaal's team have also created a similar device, the Snaplet, which can be worn like a wristband. It operates as a watch when in a convex state, becomes a PDA when flat, and can be used as a phone when turned concave.

The technology is the result of a collaboration between Queen's University and Arizona State University, and will be officially presented on May 10th at the CHI 2011 conference in Vancouver.

"This is the future," said Vertegaal. "Everything is going to look and feel like this within five years."

Source: Gizmag

New Graphene Material is Paper-Thin and Ten Times Stronger Than Steel

Graphene Paper

Researchers at the University of Technology Sydney have created a new material that is lighter, less dense, harder, and stronger than steel. But this material isn’t one of those breakthroughs that only sounds good on paper. It is paper, and it could be a game-changer for materials science if it can live up to researchers’ hopes.

This graphene paper is constructed of graphite reformed by chemical processes into monolayer hexagonal carbon lattices stacked as thin as a sheet of paper, and it is remarkably strong. To quote a press release from UTS:

Compared to steel, the prepared GP is six times lighter, five to six times lower density, two times harder with 10 times higher tensile strength and 13 times higher bending rigidity.

That’s no incremental improvement on the qualities of steel, but a huge leap forward in terms of overall material strength (plus, like paper, it is flexible). And because it is graphene, it is also imbued with some interesting electrical, thermal, and mechanical properties.

But perhaps best of all, graphene paper not outrageously difficult or expensive to manufacture, and as such it could have huge implications for the aviation and automotive industries, where manufacturers have already been turning to composites and carbon fiber materials to cut weight and thus increase fuel economies.

Source: Popsci via UTS