Silicon semiconductors have taken us a dazzling distance along the computing road. But even if they continue unabated to get faster and more powerful (and it's growing more difficult to make that happen) there's a limit to what classical computing can do.

The next real game-change in computing is quantum--tapping the quantum mechanical properties of materials to process information in ways that will make today's biggest and baddest super computers look like pocket calculators. And for the first time scientists, at places like IBM, are moving beyond just theorizing about them to actually envisioning how a finished quantum computer would work. In labs across the globe, the first building blocks of the first quantum computers are slowly becoming real.

That's huge considering a working quantum computer would be the kind of thing that truly moves the ground beneath our feet. With a relatively modest quantum computer, scientists could slice through sophisticated encryption schemes, model quantum systems with unprecedented accuracy, and filter through complex, unstructured databases with unparalleled efficiency.

But first they have to build one. The idea of quantum computing was introduced in the early 1980s by physicist Richard Feynman, and the field is still very much in its infancy. But as a discipline it's turning a critical corner as the theoretical meshes with the practical. There's more than one way to build a quantum computer, and it's still far too early in the game to know which--if any--of these approaches will produce a working system. But between all of these varied approaches to tapping the quantum world, there's one common thread: it's all about the qubit.

Like their classical cousins, quantum computers rely on units of information. In the classical world, that's a bit (a byte most commonly consists of eight bits), each of which can exist in one of two states: 0 or 1. All of your data--your MP3s, your texts, your documents, your Tumblr--are nothing more than lines of bits.

The quantum analog for the bit is called a qubit. Unlike a bit, a qubit can exist as a 0, a 1, or in a state of superposition, which in quantum lingo basically means it is both a 0 and a 1 at the same time. This is where we enter the strange realm of quantum properties, where things are anything but intuitive. "You start with a sea of all possible answers in your quantum states, and you design your algorithm to peel away the wrong answers so that the right answer emerges," says Matthias Steffen, manager of the experimental quantum computing research team at IBM Research. Rather than considering one solution to a problem at a time, you can consider multiple possible solutions simultaneously.

There are huge challenges standing between us and this mind-numbing computational payoff. Working at the quantum scale usually means working at extremely low temperatures, often bordering on absolute zero. Particles themselves are fickle. Coherence time--the amount of time the carefully cultivated quantum system is available to be read by the computer before the quantum state collapses--is measured in mere microseconds. And because there is an intrinsic margin of error in quantum computation in general, quantum computers must constantly correct themselves for errors.

Then there's the problem of measuring quantum states, which tends to cause them to collapse. This requires a mastery of quantum correlation or entanglement--a strange quantum phenomenon that links the states of two particles together even across distances such that affecting one affects the other--so that researchers can actually measure their quantum systems without destroying them. Needless to say, absolutely none of this is easy.

That's why researchers are starting small, pouring their brainpower and research dollars into developing a single, stable qubit--and eventually strings of tens, then hundreds, and then thousands and tens of thousands of qubits. So what might the quantum computer of the future look like? We're not exactly sure yet, but there are a few different approaches showing a lot of promise.


Artificial Atoms/>

There's more than one way to make a qubit. All you really need is something that can provide two different and defined quantum energy levels to serve as analogs for the 0 and 1 in a classical scheme. Many potential qubits are natural phenomena, manipulating the quantum characteristics of atomic nuclei, ions, or electrons to encode information into a quantum system. But what if you could manufacture qubits artificially with whatever properties you want them to have?

This approach has spawned an entire branch of quantum computing research that is trying to perfect the superconducting qubit. Perhaps unsurprisingly, IBM Research has emerged as one leader in this space, as the approach meshes nicely with the company's expertise in superconductivity, microfabrication, and--perhaps most importantly--the scaling of technologies into finished products.

Stripped of a lot of complex physics, it's easy to think of a superconducting qubit as an artificial atom. Technologically speaking, a superconducting qubit involves two superconducting materials running an oscillating current across a device called a Josephson junction, which through the magic of quantum physics allows the qubit to carve out just two oscillation frequencies of the many that the current might have and use those frequencies as the classical 0 and 1 (there's a lot of quantum mechanics involved that we won't get into here, but suffice it to say that controlling these oscillations satisfies the fundamental requirements for a qubit).

The main advantage of superconducting qubits is that they are manufacturable, and therefore lend themselves to customization and eventual scalability to a larger quantum computer possessing hundreds or thousands of qubits. But even the team at IBM--which recently demonstrated record-setting coherence times of up to 10 microseconds and error correction with a 95 percent success rate--knows that it's far too early in the race to declare their method a winner.

"The superconducting approach has great potential and we think its the front-runner and that's why we're working on it," says Mark Ketchen, a physicist helming IBM Research's Physics of Information initiative. "But it's early in the game and things could change. Five years from now the system could look very different."

Tapping Electron Spin

That's because superconducting qubits are far from the only game in town. At Harvard University, Dr. Amir Yacoby is exploring the possibility of encoding information via the spins of the electrons inside quantum dots--tiny semiconductor crystals with unique electronic characteristics. Broadly speaking, electrons have two possible spin states--call them left and right--that can represent the 0 or 1 state of a classical bit. Trapped in a quantum dot, electron spin can be measured and manipulated. But this introduces a problem that is common across quantum computing.

This is the same problem introduced by Schrodinger's Cat, a common paradoxical problem when dealing with quantum systems (for a deeper understanding of all this, read up on the infamous cat and quantum entanglement). To create a usable qubit, researchers want something that is good at decoupling itself from its environment, something that won't be influenced by external factors. At the same time, it's necessary to have something that can be manipulated by external forces so the computation can be controlled.

Finding something that satisfies these contradictory needs of a viable quantum computing system isn't particularly easy, but electron spin goes a long way toward serving both sides of the paradox. Spin lives for a long time, atomically speaking, so you can encode information in the spin and it will exist in the system for a relatively long time, contributing to better coherence. Electrons trapped in quantum dots can be coaxed into decoupling from their environments while still responding to weak magnetic fields--fields that are weak and predictable enough that even when they introduce error-producing noise into the quantum system, it's relatively easier to correct the errors.

Still, spin isn't immune to the problems dogging many in the quantum computing community who are trying to do very big things with very small particles. As with superconducting qubits, quantum dot computing would have to happen at very cold temperatures--something like a tenth of a degree above absolute zero. And all quantum complexity aside, the engineering challenges inherent in fabricating such a system with more than a few qubits are daunting. But Yacoby is unfazed.

"I think we're going to encounter a lot of discovery before we have to face the engineering challenges in cooling down one thousand or ten thousand qubits," Yacoby says. "I'm optimistic--very confident--that that level will be met within my lifetime."


Trapping Ions/>

But you don't have to go all the way down to the subatomic to find good candidates for qubits. Ions--atoms whose electrons and protons are out of balance, giving them a net charge--can be fantastic qubits, wherein the spin of the nucleus represents the 0/1 classical states. Trapped by an electric field and laser-cooled inside of a vacuum chamber, ions are very well isolated from external factors that could mess with their fragile quantum states, giving them very long coherence times. The fact that they are charged also makes them far more manipulable--via electric fields--than neutral atoms.

But while it's easy enough, relatively speaking, to trap one ion (or even a few ions) in a vacuum chamber, a system dependent on highly-tuned electric fields and cooling lasers that need to be switched on and off with very precise timing becomes vastly more complex with each additional ion. When you start to think of dozens or hundreds of qubits, the idea of scaling this kind of system becomes the primary challenge.

"You can't just build a hundred or a thousand or a million of them on a chip like we do with transistors," says Boris Blinov, an associate professor of physics and principal investigator at the University of Washington's Trapped Ion Quantum Computing Group. "That's how we scale regular computers today. With ions, you have to figure out a way of arranging them in one location in such a way that they will interact in the ways necessary for quantum computing. In this way, ions are at a disadvantage."

Blinov and his team are working to circumvent this problem via a modular approach that employs many microfabricated ion traps. Each chip-like trap would hold several ions--but not too many--and interaction between chips would be accomplished by beaming photons around the system via a network of fiber optic cables. By entangling these single photons with the trapped ions and beaming them around the system, ions on different chips in a system could interact at the quantum level.

Sound mind-bendy? It is. But working with barium ions Blinov and his group are making slow but steady progress. If they or another research group can solve the scalability problem--and right now, "ifs" are abundant in this field--ions could turn out to be viable qubits in a future quantum computer.

The Supercomputer of the Future

Of course, the same could be said for any of the aforementioned potential qubits, and for any number of other approaches to quantum computing inching forward within the global physics community. The method that finally produces a working quantum computer--maybe sometime in the next decade, maybe beyond that--could be one of the ones mentioned above, another avenue that is just beginning to be researched, or one not even conceived of yet.

"It's very important to remember that this is still a scientific endeavor," Harvard's Yacoby says. "Our trajectory is constantly interrupted by things we discover. Sometimes we think one thing and it turns out to be something else. This can be an obstacle, but some of those discoveries turn out to be quantum leaps forward. We're finding things we didn't know as we go along, and our trajectories are corrected."

But while the road ahead is shrouded in a mysterious quantum fog, there is some consensus about what a finished quantum computer will look like. For one, it will have a classical component to it that will actually run the quantum algorithms within the quantum computer. It will be large, comprised of both a classical supercomputer and the quantum computer, which--depending on the qubits--could be a series of vacuum chambers and optical tables, or row after row of super-cooled chambers for cooling particles down to nearly absolute zero (or something else entirely).

This construction, whatever it will be, presents a challenge in itself. Classical electronics perform more and more poorly the lower the temperature goes, so interfacing classical and quantum computers that require low-Kelvin temperatures will require feats of engineering that current technology cannot adequately solve. But by and large, those working in the quantum computing community believe that in the time it takes them to build their perfect qubits, the practical engineering issues will also sort themselves out. And when they do, researchers believe we'll unlock a kind of computing power that will drastically impact the entire spectrum of human knowledge--even in ways we haven't thought of yet.

"It's not so straightforward to predict where computing goes," says IBM's Steffen. "If you were to ask the folks that invented the people that built the transistor where it was going, they couldn't have imagined what it would one day lead to. The same is true for quantum computing."

Worried about the safety rating of that child car seat? Perhaps you should swaddle your progeny in a protective Kevlar cocoon. The Carkoon is a new child seat developed by British company Cool Technologies that wraps your child in protective Kevlar and a fireproof Nomex airbag upon impact. It even calls emergency services for you.

When deployed, the airbag shields the entire exposed portion of the car seat, protecting the child inside from flying objects (or flames) inside the car using the same materials used in body armor and fireproof suits. And should the driver be incapacitated, an emergency transmitter begins beaming the GPS coordinates of the seat to emergency channels. Which means you can rest assured that although you may be on fire, junior is comfortably awaiting help to arrive.

The seat is currently a prototype but could go on sale as early as next year for around $800, cheaper than your designer stroller.

As spaceborne energy-harvesting schemes go, this one seems faintly possible - an array of curved mirrors directing sunlight toward solar cells, their energy production microwaved down to Earth. It's so realistic, actually, that NASA is providing funding for a proof-of-concept study.

A former NASA engineer named John Mankins, now with a company called Artemis Innovation Management Solutions, detailed his plans at a NASA innovation conference recently. The concept is called called Solar Power Satellite via Arbitrarily Large PHased Array (SPS-ALPHA), and it would harvest solar energy from a perch in high Earth orbit.

It would consist of a modular array of movable thin-film mirrors, which could be taken into space using current cargo ships and assembled piece by piece. This would be less expensive than building a gigantic array and launching it. These curved mirrors would redirect sunlight toward an internal collection of photovoltaic panels, and the solar energy would be converted into microwaves. Then the Earth-facing portion, or the bottom of the margarita glass in the image at top, would transmit low-frequency, low-intensity waves toward Earth. At the receiving end, power plants would convert the microwave energy into electricity, adding it to the power grid.

It's not as comprehensive - nor potentially destructive - as building a Dyson sphere around the Earth, but it's sort of along the same lines, building a space-based system that can harness solar radiation and somehow beam it back to the planet. Mankins' design is inspired by nature, according to an account of his presentation over at Space.com. It does sort of look like a flower.

His project, first announced last fall, is part of NASA's NASA Innovative Advanced Concepts project, under the Office of the Chief Technologist. A one-year study is ongoing.

[via PhysOrg]

It was once thought that vacuums--like the vacuum of space--contained nothing. No particles, no sound, just empty darkness. But it has since come to light, thanks to discoveries in quantum physics, that virtual sub-atomic particles constantly and spontaneously appear and disappear, even in the void. Which doesn't mean a whole lot unless you're trying to build the ultimate random number generator.

Tapping this spontaneous cascade of sub-atomic particles within vacuums, scientists at the Australian National University have built the world's fastest random number generator by listening in on the action. Using lasers, the team has created a device that can listen to the random noise in the vacuum and use it to generate truly random numbers, which have myriad uses in encryption, information technology, computer modeling, and other complex tasks.

Most existing random number generators work off of some kind of computer algorithms. Those algorithms are pretty good, but if you know the inputs you can figure the outputs. In other words, the numbers aren't truly random, they are just correlated in a way that is unknown to the user. But Vacuum noise is truly random--quantum theory ensures the numbers are truly unpredictable. By measuring the noise in a vacuum, the team can generate billions of random numbers per second. The only thing limiting them in their ability to flood the world with random numbers is the capacity of their Web connection.

But that doesn't mean you can't get your very own sequence of unique random numbers off the Web. Access ANU's randomness generator here.

[PhysOrg]

Next time you visit Canada, you might use digital currency to purchase your poutine, using something called MintChip backed by the Canadian government. The Royal Canadian Mint announced it's getting rid of the penny and starting a new e-currency instead, and it wants the software community to help develop it.

The government just launched the MintChip Challenge - which was apparently so popular it's already fully registered - to seek new digital payment apps for this new virtual currency. The idea is sort of a hybrid, combining the convenience of electronic transactions and the anonymity of cash. It will work via SD cards, but it will have no personal information or bank account data associated with it. It's sort of like BitCoin but with actual, government-backed value.

The four-month contest includes 500 developers who will build apps that can demonstrate MintChip's value. They'll have to work on a variety of smartphone and desktop browsers. The prize: Solid gold wafers and coins worth about $50,000.

Its anonymity is a pretty unique idea. Other electronic payment systems - PayPal, Square, NFC-enabled phones, etc. - all connect to a person's credit card or bank account. But cash is a great equalizer; you don't need to have good credit to use it. MintChip would enable the same type of low-cost transactions for which you'd normally use cash. A Canadian banking group called Interac estimates that small-value transactions under $20 are worth $90 billion to the Canadian economy, the Toronto Star reported.

MintChip still has some kinks to be ironed out, including privacy, security of the currency and other questions. But it's certainly an interesting concept.

[via Slashdot]

The workhorse of the European Space Agency's earth observation initiative went silent over the weekend, and the agency admits today that it hasn't heard a beep from the aging satellite since Sunday. The nearly-nine-ton spacecraft is in a stable orbit, but if the problem persists the ESA may have to finally retire Envisat, which has been in orbit twice as long as it was designed to be.

ESA's mission control first called a spacecraft emergency on Sunday when the spacecraft unexpectedly went silent as it passed over a ground station in Sweden. Since then, the ESA has requested help from ESA tracking stations across the globe, but so far the satellite remains uncommunicative.

The team is still trying to re-establish contact, but if it cannot the ESA stands to lose one of the world's most sophisticated Earth observation satellites. Envisat's 10 instruments provide data on land masses, sea ice, atmosphere, and ocean conditions. In terms of its mission, Envisat has long outlasted it's packaged expiration date, which came and went back in 2007 (Envisat launched in 2002).

But from a capabilities standpoint, losing Envisat would mark a setback for the ESA's ongoing earth science program. The agency had hoped the satellite would remain in service until 2014, by which point the first of its Sentinel satellites--the successors to Envisat's mission--would be in orbit. The first of those satellites is slated for launch next year, but the ESA hoped to have both Envisat and that first Sentinel in service for a period of overlap so they could calibrate their data. As things stand this morning, the ESA could instead be facing a bit of a science gap until the Sentinel missions get underway.

[ESA]

Sometime soon, when you spot a pothole in the street, you won't have to swerve around it and curse when your wheel dips in. Instead, you would deliberately drive over it, so the pressure of your car tires will stiffen the little plastic baggie the city dropped in there as a temporary fix. A little non-Newtonian fluid pothole filler could spare your wheel alignment after a harsh winter, saving municipal money and traveler troubles.

Non-Newtonian fluids are those that ooze in some conditions and stiffen in others as they respond to forces applied to them. Newtonian fluids, by contrast, act like fluids no matter what's done to them. The classic mixture of cornstarch and water is one example of a non-Newtonian fluid. A group of students at Case Western Reserve University in Cleveland decided to use these mixtures as pothole fillers, as part of a contest by the French materials company Saint-Gobain, according to ScienceNow.

Here's how it could work: Instead of driving around with a mixture of hot asphalt, road-repair crews or even police cars would carry plastic bags full of a water-powder mix. The students plan to patent their idea, so they haven't divulged their recipe, but they say it's biodegradable and even edible. When a city worker comes upon a pothole, he or she would drop a baggie into the hole, and then cover it up with black tape so a driver wouldn't mistake it for an obstacle. When a car drives over it, the fluid behaves like a solid - voila, a filled pothole.

This is because it's a shear-thickening fluid, as ScienceNow explains. Where shear-thinning fluids will squirt and flow when a force is applied, shear-thickening fluids will stiffen up, behaving more like a solid. Like this.

The students have already road-tested their plastic bag trick and say it holds up well, even after a week of continuous use. They are meant to be sturdy enough to last weeks at a time, even in wet and salty-road conditions, until pockmarked roads can be properly filled and smoothed over, the team said. The city of East Cleveland plans to help with further testing, ScienceNow said.

[ScienceNow]

If you fear the robot apocalypse, perhaps your day would be much improved if you just moved on. Boston Dynamics' PETMAN robot, developed for DARPA, is getting more humanoid-like by the day it seems, and here we see it--legs, torso, arms, and all--negotiating staircases, running on a treadmill, and even hitting the floor for some pushups. All this strength training appears to be doing PETMAN some good.

A modified version of this platform will be used as the government-funded equipment for the tracks of DARPA's Robotics Challenge that only require teams to develop a software component. In other words if you can write a good piece of software for this high-stepping humanoid, DARPA might just let you try it out.

The first human eggs grown from human stem cells could be fertilized with human sperm cells later this year, potentially revolutionizing fertility treatment for women. This could be one more step on the path toward reproduction sans human interaction - in this case, a potential parent wouldn't even need to donate her eggs. But it could also turn stem cells into an infinite loop, of egg cells into embryos into stem cells, and on and on, in a fractal-like repetition of reproduction.

In February, we heard about a study involving Japanese women whose reproductive stem cells were donated because they were undergoing gender reassignment surgery. Researchers at Massachusetts General Hospital were able to coax these ovarian stem cells into becoming immature human egg cells, which were then incubated in mice so they'd have the proper ovarian structures. Now these same scientists, working with a team at Edinburgh University, want to fertilize them.

After sperm implantation, the scientists would watch the blastocysts develop into embryos for two weeks - the legal limit - and determine if they're viable. Then these embryos would either be frozen or "allowed to perish," according to the Independent. The tests would validate the stem-cell-derived human eggs, more properly called oocytes, and serve as an early indicator of whether they could someday be used to eradicate infertility.

Stem-cell derived oocytes could replenish the stocks of women undergoing menopause, or they could be used to allow infertile women to reproduce. The Independent goes so far as to mention an "elixir of youth," wherein women of any age are full of stem-cell derived oocytes, remaining fertile and youthfully healthy forever.

This potential stem cell-based embryo construction still faces some hurdles - reproductive biologists are applying for a license to the Human Fertilisation and Embryology Authority in the UK. But if it's approved, the eggs could be fertilized this year, according to the Independent.

Stem cells hold such great promise because they can differentiate into any cell, potentially replacing neurons, islet cells, kidney cells and more. But this research conceivably turns stem cells into an infinite supply of cellular material. The stem cell eggs would obviously most likely be used to help women conceive a child, but it's not a huge leap to much more frightening scenarios: Stem cells turned into human egg cells, which could be fertilized to grow embryos, which would contain more stem cells, which could in turn be harvested .... and so on, as self-contained stem cell factories. It will be interesting to see how the UK authority interprets the possibilities.

The Pentagon wants cyberweapons, and it wants them fast. Deftly recognizing that cyberweapons are nothing like the materiel of physical warfare, the DoD is devising a means to fast-track and field certain cyberweapons, some of which will take only days to go from development to deployment.

The Washington Post has obtained a Pentagon-prepared report for Congress outlining and acquisition process that will respond to "mission-critical" needs when cyber weapons are absolutely necessary and time isn't on the side of U.S. personnel. It's a strategy that addresses the fact that cyberwarfare isn't like anything that's come before it.

In conventional warfare, you build your weapons, you warehouse them, and if the time comes, you pull them out of storage and you deploy them wherever in the world they are needed. Procurement times are long, but so is the shelf life of something like an F-16--an all-purpose platform that can flies and fights the same way regardless of hemisphere. Cyberwarfare is nothing like this. Generally, a specific threat requires a specific response, and specific cyber targets require specific cyberweapons that may be used once and never used again. As such, cyberweapons can't effectively come off the shelf. They have to be tailor made for the situation, and fast.

To that end, the two-year-old Cyber Command is in the process of inventorying the Pentagon's current cyber capabilities and basic off-the-shelf cyberweapons platforms that could be quickly tailored for specific tasks. It will then set up two different silos of cyberweapons development. In the rapid silo, cyberweapons will be developed in months or even just days from existing or nearly complete hardware and software assets to deal with immediate threats. The deliberate silo will house cyberweapons that are designed over longer timelines for specific purposes but whose deployments are far riskier ("cough STUXNET cough").

It's important to note that these cyberweapons won't just be defensive, but offensive as well. Which is troubling in its own way, since the building of new and powerful offensive weapons tends to lead to escalation. But at least it shows that the Pentagon fully (and finally) grasps that this kind of warfare requires a high degree of nimbleness. In the same way that you don't want to show up to an IED fight with an unarmored humvee, you can't expect to compete in the cyber conflicts of the future with yesterday's cyber tools.

[WaPo]

Today, Barnes & Noble announced a new upgrade to the (pretty excellent) Nook Simple Touch ebook reader: illumination. The Simple Touch With GlowLight, as it'll be called, is in just about every way the same as the non-bright Simple Touch, except it has a little LED at the top of the screen so you can read it in the dark without an external light source.

Electrophoretic displays like the Nook's (and the Kindle's, and the Kobo's, and the Sony Reader's) function in practical use basically like a sheet of paper. That means they're super easy on the eyes, since there's no light shining in your eyes all the time as with an LCD (like on a tablet or smartphone). But it also means that they're hard to read in low light, since they don't provide any light of their own.

The Simple Touch With GlowLight (awkward name! I'm going to call it the GlowNook from now on) isn't the first LED-lit electrophoretic reader--Sony's had one for awhile--but it's the first one that really works. Sony's had serious glare problems, and the lighting itself wasn't even. The GlowNook is front-lit by a strip of LED light at the top edge of the screen, and some kind of proprietary system of (invisible) lenses and prisms bounces the light back and forth for more evenness. (My finger did not cast a shadow.) I'm not sure exactly how it works, but it lines up with this TechCrunch report on new electrophoretic screens (rumored to be included in the next Kindle as well). It does in fact glow softly, rather than harshly, but Barnes & Noble told me the LED is on top of the screen rather than below it.

It is definitely brighter right up at the top, but from about a centimeter down until the very bottom of the screen, the GlowNook remains evenly lit. The lighting is grey, too, which is good. Not yellow, not blue. On the Wikipedia shades of gray scale, it's about a silver. It's a nice color, silver. Elegant and understated. Good gray.

And there's an anti-glare film built in--previously this was available only as an option--so there's very little glare at all. (Glare was an issue in the Sony LED-lit reader, making it harder to see in sunlight.)

I found it very comfortable to read in the dark, so it's a good option if you do a lot of that (or if a bedside lamp disturbs your sleeping partner).

It's easy to use; you just hold down the Nook/home button, located on the front of the screen, for a couple seconds and the light pops up. There's a sliding bar so you can adjust the level of brightness--in all likelihood, you'll want just a touch of light, and that option is certainly there. Using the touchscreen doesn't affect the light, since the light is below the outer anti-glare coating. Otherwise it's about the same as the regular Simple Touch, which, by the way, it's not replacing--it'll be available alongside its dark little brother. Using the light cuts the battery life, but not by too much--B&N claims a month of battery life when lit, and the regular two months when dark, so it'll still be a long-lived gadget.

The new Simple Touch will be available for pre-ordering on April 12, with availability sometime in early May, for $139. That's a fair price; the Kindle Touch, which I actually didn't love, and which does not have an included light, also costs $139 in its ad-free model (with ads, it's only $99, and the ads are pretty inoffensive, so.). But I actually like the Simple Touch more than the Kindle Touch--the Simple Touch retains its page-turning buttons, which for me are a much better option than swiping the screen--so if you're not locked into Amazon's Kindle store already, it's definitely worth taking a look.

Splitting the world's largest radio telescope across half the Earth could resolve an international quarrel that is brewing between two continents, researchers say. Australia and South Africa are vying to host the Square Kilometer Array, which will peer back to the early universe, and now it's getting political.

The SKA will be an enormously expensive array, requiring ultra-powerful computers to process its extreme amounts of data, and whichever country hosts its dishes will see a raft of new funding and international astronomical prestige. Last month, South Africa won the recommendation of the SKA Site Advisory Committee, which found the country offered slightly better opportunities, Nature News reports. But officials in Australia and New Zealand, the other competitors, have ramped up their lobbying efforts.

The SKA planning teams met last week in the Netherlands to discuss next steps, and now they're considering dividing up the 3,000 antennas and other equipment between the two sites.

"[The members] noted that it is important to maximize the value from the investments made by both candidate host regions," SKA Organization leaders said in a statement. The organization set up a small working group to explore how this could work. One option, likely the cheapest, would set up the array's high-frequency antennae on one continent and the low-frequency array on the other, according to Nature News.

If this really happens, it will introduce even greater logistical challenges to an already overwhelmingly complex project. Data crunching, storage and transport is already a massive challenge for the SKA, which will require the next generation of supercomputers to work efficiently. Dividing this work among two continents separated by hundreds of thousands of miles would be even trickier - imagine the latency challenges, for instance.

The working group is scheduled to report back at the next meeting in mid-May.

[Nature News]

Nap Pepin had been waiting on the side of the highway near his Alberta, Canada, home for more than hour when the tow truck finally pulled up. The driver looked at the stranded electronics technologist and his homebuilt electric trike and asked, "Ran out of juice, eh?" Pepin wasn't sure what the problem was, but he knew he still had plenty of charge. He had been tinkering with battery-powered three-wheelers since 2005, and by that point, late last year, he had spent hundreds of hours designing a battery pack to ensure that his vehicle, the Lithium Hawk, would never unexpectedly lose power.

Pepin, 48, has been making vehicles since he was a kid. After building an electric trike using some parts from a kit in 2010, he decided to make his own three-wheeler from scratch. He designed an aluminum chassis, chose an AC motor that could handle the trike's 1,000-pound estimated weight without overheating, and selected a pair of car wheels for the front. He wanted the trike to be rear-wheel-drive, so the back wheel was critical. Conveniently, he found several people who had converted Honda Goldwing motorcycles into standard gas-powered three-wheelers and no longer needed the shaft drive that powered the bike's rear wheel. The shaft drive was ideal for his project, in part because it allowed him to outfit the trike with highly efficient tires. He bought one, originally priced at $3,500, for $106 on eBay.

Despite all the mechanical engineering involved, the batteries presented the biggest challenge. Typically, as lithium cells run down, their performance degrades. Pepin wanted his vehicle to be more like a gas-fueled car, which provides more-consistent acceleration. So he ordered several types of lithium batteries, bought testing equipment, and spent two months analyzing the batteries' performance under a variety of conditions.

When he found a winner, he worked for another few months on a copper-plated pack to encase the 1,976 cells. He spent more than 100 hours precisely welding the copper around the batteries, only to find that the welds weren't holding. That forced him to get rid of the copper and start over with strips of nickel, which he spot-welded together with the cells at 23,712 different points.

Pepin may build a real body for the Lithium Hawk to increase its range, but right now he thinks it looks cooler without one. The vehicle gets plenty of attention and is street-legal. Pepin discovered that a manufacturing flaw in the motor controller caused his highway breakdown, and he has now corrected it. He's also designing a system that will regulate the power sent to the battery pack to maintain a constant temperature, so that the Lithium Hawk will perform as usual even in the subfreezing Canadian winter.

Building an Electric Bike

Time 2 years
Cost $24,000

/>

HOW IT WORKS

Steering: Pepin knew the Lithium Hawk would have to be registered as a motorcycle, so he opted for handlebars instead of a rack-and-pinion system; he was worried that the regulatory authorities might not approve a steering wheel. The handlebars he used initially were difficult to turn at low speeds, so he had to entirely rebuild the front of the chassis. (When he had the vehicle inspected, the regulators said they would have been fine with a steering wheel.)

Brakes: The vehicle has hydraulic brakes, but Pepin mainly relies on a regenerative braking system to stop. When he wants to accelerate, he twists the handlebar throttle toward himself, and to slow down, he turns it away. This sends a signal to the motor controller to slow the rear wheel. The Lithium Hawk's motor behaves as a generator, and the controller captures the excess energy that's produced and routes it to the cells, extending the vehicle's range.

Performance: Pepin has driven more than 2,000 miles in the Lithium Hawk, and he says it out-accelerates practically every other vehicle on the road. He can jump from 45 mph to nearly 70 in about two seconds. At this point he won't estimate the actual range of the vehicle, in part because it's a skeleton. Had he decided to enclose the Hawk in an aerodynamic shell as he initially planned, the range would increase significantly at highway speeds.

With a crucial test flight of its Falcon 9 rocket and an unmanned Dragon capsule slated for later this month, commercial space outfit SpaceX is nearing the crescendo of its unmanned space launch program--a robotic rendezvous with the International Space Station. Next up for SpaceX: doing the exact same thing, but this time delivering humans rather than cargo into orbit.

To that end, SpaceX announced last week that it would convene an independent safety advisory panel staffed with former astronauts and NASA researchers to provide an objective review of the Falcon 9 and the DragonRider, SpaceX's crew-capable variant of its Dragon capsule. The company says it wants to create the world's safest human spaceflight system--no easy feat considering how very dangerous place space can be.

So as SpaceX shifts its focus from unmanned rocket launches to the future of manned spaceflight, PopSci caught up with SpaceX's own Dr. Garrett Reisman, former NASA astronaut and ISS crew member now bearing the title of DragonRider Project Manager in SpaceX's manned spaceflight program, to talk about the process of building a manned space launch vehicle from the ground up and how exactly SpaceX plans to build the safest spacecraft the world has ever known.

PopSci: Why convene this independent safety advisory panel? Naturally SpaceX wants to boost human safety across the board, but what do you hope to learn from this particular group of individuals that SpaceX doesn't already know?

Reisman: We're entering a new phase here where we're focusing more and more on flying people into space. There's a big difference between flying a bunch of cargo up to the space station and flying people up to the space station. The level of safety and concerns, the implications of something going wrong--it's an entirely new and different ballgame.

" What you worry about are the unknown unknowns--the things that you haven't prepared for."We want to make sure we have every opportunity to catch any potential problem that could lead to a safety issue. So we're creating this independent safety advisory panel with these leading experts outside of NASA. By bringing in all their experience, we feel like we're getting the best possible set of advisors that can ensure we're moving in the right direction. But it's important to note that NASA itself performs a very similar function through the commercial crew program. They have both an insight team and an oversight team that will be providing us with excellent advice. So this panel will supplement that. We feel that the skilled team that we have here at SpaceX coupled with the experience of NASA and all their lessons learned as well as these independent safety experts puts us in a really good place to ensure that our manned vehicle achieves a level of safety that's going to be better than anything that's preceded it.

After so many trips into low Earth orbit, it's easy for many people to look at human spaceflight as fairly routine even though we've been tragically reminded a few times that it is in fact a very dangerous undertaking. Are there any specific places in the overall human spaceflight scheme--any particular points of worry--that SpaceX is focused on?

There are a lot of particular technical areas that have been problematic--the main propulsion system or the thermal protection system--where we've learned the painful lessons of the past. What we've striven to do is to build a vehicle that is much more safe than anything available now or that was available in the past. One of the ways we do that is by minimizing possible things that could fail. A lot of safety comes from simply having a robust and straightforward design that minimizes the number of failure modes.

But a lot of times when you have an accident or a mishap in aviation or in space, it's caused by a failure of imagination. What you worry about are the unknown unknowns--the things that you haven't prepared for. By bringing these people in--both the people with NASA and this independent safety advisory panel--they will bring with their experience an ability to protect us from that failure of imagination. They'll make sure we don't overlook anything, that there's nothing they can think of that we haven't thought of.

It seems like in building any manned spacecraft system there has to be some kind of tradeoff between comfort, cost, and safety. How do you establish where to draw those lines?

Safety isn't always a function of money. Sometimes too much money can be a curse. If you take the approach that you're going to take every kind of risk you can conceive of and drive it down to zero, you're going to build a rocket that can never get off the ground. As with any ship, the only way to be 100 percent safe is to never leave the harbor. There's always going to be some level of risk, and the trick is to find all the critical ones, the ones that could lead to a truly catastrophic event.

There's one common enemy to both cost-effectiveness and safety, and that is complexity. If you design a vehicle that is incredibly complicated, you get a vehicle that is both very expensive and not very robust, and certainly not very safe. What we've done is design a vehicle that eliminates unnecessary complexity. That makes it easier to manufacture and brings the cost down, and it means there are fewer things that can go wrong.

A good example is our launch abort system. In the past, or even if you look at the Soyuz today, there's a tower on top of the spacecraft with a solid rocket motor on top of that, and if you ignite that motor it pulls you away like an ejection seat if, for instance, the rocket is about to blow up. If you have a tower like that and everything goes well, you still have to jettison it because you can't deploy the parachutes, the tower is in the way. Now you've created something else that has to go right every single time--it's like an ejection seat you have to use every time you fly.

What we've done is incorporate our launch abort system into the sidewall of the vehicle. That does a bunch of things for you. Now, if you're having a good day, you don't have to rely on a mechanical event to go right in order to stay safe. That necessity has been eliminated. At the same time you carry these rockets with you and bring them back, so you don't have to throw them away. And since you carry them with you all the way through, you can conduct a powered abort anytime, all the way to orbit. So we've decreased cost and increased safety all in one stroke. That's what you want to do.

The last time NASA really built a manned spaceflight system from the ground up it was the 1970s. In the intervening forty years we've undergone a period of unprecedented technological development. How is building a manned spaceflight system in 2012 different than it was, say, when the shuttle program was getting underway?

We have a huge advantage in that we can learn from the past, so we don't have to reinvent the wheel. They did a lot of great work at NASA during the Apollo era and during the shuttle era, and we're the beneficiaries of that. They share their lessons learned with us and they're looking over our shoulders to make sure we don't repeat a mistake of the past. So it's a huge advantage.

The other advantages we have are, of course, modern electronics and computing power. We have the ability to create much more capable fault detection systems that give us plenty of warning time. When something does go wrong, you have time to act. It goes back to what I was saying before: accidents are so often caused by a failure of imagination. They had to have so much more imagination back then because no one had ever done this before. The burden on our imagination is less. Still, we have to remain vigilant. There's always something lurking out there that we haven't thought of before.

A thousand years ago, Vikings navigated with a sunstone, which they used to locate the sun on cloudy days. The stone-a calcite crystal called Iceland spar-funnels light into two beams. When the beams appear equally bright, the rock is facing the light, even if it's obscured. Researchers now use calcite to funnel light around tiny objects for "invisibility" cloaks.

This week in images: beautiful pictures from space--and a picture of a rocket that didn't quite make it. Snail therapy and pink leopards. Robots made from vacuum cleaners and a picture of London, illegally taken from the top of the unfinished Shards of Glass skyscraper. Click through, look, enjoy, wonder.

Click to launch the gallery.

The current and next generation of tablets are getting into a core war: three, four, even five cores are going to be popping up in your Android (and possibly iOS and Windows) tablets. But what's the point of this numbers battle?

THE TREND

Most tablets fall into one of two categories: low-power devices that last for a day in standby mode but sputter when playing high-def games, and high-power models that handle demanding tasks but suck power in standby. Nvidia engineers combined a low-power single-core CPU and four high-performance CPUs onto the same die, allowing tablets to run efficiently in any situation. This Tegra 3 chip is already in high-end tablets, but manufacturers will use it in more devices, including phones, in the future.

THE BENEFIT

Because the Tegra 3's cores run only when needed, tablets can last for as long as 12 hours on a charge. Additionally, its quad-core chip-prior devices were dual-core-will make games render faster and with more-realistic textures than before. Simpler media apps will run more smoothly, too; Photaf 3D Panorama, a popular Android photo app, renders twice as quickly as with previous chips.

Here are some of the features of the new crop of Tegra 3 tablets:

Quick Access: Software designers at Acer made a single modification to the stock Android operating system in their 10.1-inch tablet: a quick-access pop-up menu. From the circular menu, users can easily jump among tasks, apps and recently visited sites.
Acer A510 $450

Business-Ready: With its keyboard dock attached, the Transformer Prime morphs from a tablet into a de facto mobile workstation. The dock also houses an extra battery, which increases the tablet's standalone runtime from nine to 16 hours.
Asus Eee Pad Transformer Prime From $500; keyboard dock, $150

Media Savvy: Lenovo engineers built the LePad K2010 with two speakers flanking either side of the 10-inch high-def screen. The speaker drivers are programmed to use acoustic tricks that create the illusion of surround sound within three feet of the screen.
Lenovo LePad K2010 Price not set