quantumphysics
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Entangled photons on a chip could lead to super-fast computers
Photon entanglement is one of the odder properties of quantum physics, but it promises a lot for computing -- if one photon can instantly affect another no matter how far away it is, you could make super-speedy computers and communications that aren't easily limited by physical distances. It hasn't been easy to get entanglement tech down to a manageable size, however, and that's where Italy's Università degli Studi di Pavia might just come to the rescue. Its researchers have developed a tiny emitter that could pump out entangled photons as part of an otherwise ordinary silicon chip. The device, which uses a ring shape to both rope in and emit light, measures just 20 microns across. That's hundreds of times smaller than existing devices, which are comparatively gigantic at a few millimeters wide.
Quantum physics theory is easier to understand than you think
Wrapping your head around quantum physics is tricky, no matter how well-educated you are -- if it were easy, there wouldn't be problems making quantum computers. However, researchers at the National University of Singapore believe they've found a way to make things simpler. They've determined that wave-particle duality (where quantum objects behave like waves) is really a manifestation of the uncertainty principle, which limits your ability to know two related properties of a quantum particle. As it turns out, you can rework the math for wave-particle duality to apply to certain uncertainty relations. They're just two sides of the same coin.
Deepak Chopra: the spiritualist as technologist
Deepak Chopra has an app. And that's about the least of the famed spiritual guru/physician/alternative-medicine advocate/friend of Oprah's technological ambitions.
Researcher finds a way to mimic curves in space-time
Here on Earth, it's rather difficult to replicate curved space-time -- to get that kind of effect in nature, you'd have to get uncomfortably close to black holes and other distant space objects. However, researcher Nikodem Szpak may have found a way to simulate that bend without facing oblivion. His proposed technique puts supercooled atoms in an optical lattice created by a laser field; so long as the laws of quantum mechanics and thermodynamics hold true, the atoms should behave like they're experiencing curved space-time. You can even change the lattice's pattern to mimic different circumstances, whether it's a moment right after the Big Bang or the surface of a star.
Scientists catch Schrödinger's cat with quantum physics
Schrodinger's cat, the good ole thought experiment that's been twisting (non-Quantum physicist) brains for decades. Scientists might have just caught it. Or not. Typical. What you see above is a combined image where a stencil was bombarded with cosmic rays photons, but the photons that generated the image actually never interacted with the stencil -- stay with us. It was separate photons (which shared the same quantum state as the ones that hit the camera) which arrived at the stencil. The science goes that when two separate particles are entangled, their physical properties appear to correlate and they share a single quantum state.
Scientists simulate time travel using light particles
We may never see practical time travel in our lifetimes, if it's possible at all. However, a team at the University of Queensland has given the Doc Browns of the world a faint glimmer of hope by simulating time travel on a very, very small scale. Their study used individual photons to replicate a quantum particle traveling through a space-time loop (like the one you see above) to arrive where and when it began. Since these particles are inherently uncertain, there wasn't room for the paradoxes that normally thwart this sort of research. The particle couldn't destroy itself before it went on its journey, for example.
Quantum data lock promises leak-proof security
Quantum cryptography is secure against intruders, since you can't intercept data in mid-flight without ruining it. The technology won't always stop leaks, however, which is why the University of Cambridge has developed a new protocol that keeps participants honest. The method combines the theories of both quantum physics and special relativity to preserve data in a locked state that isn't readable unless the sender provides a key; the laws of physics prevent anyone from decrypting the info beforehand. While we won't see any practical application of this quantum lock for a while, it could prove vital to financial traders and others who can't always trust their contacts.
Bristol physicists working to bring quantum cryptology to our phones
It's no secret that our phones are often vulnerable to the occasional malicious hack, no matter how much we believe our passwords to be secure. But what if the encryption methods we used were based on the laws of physics instead of just mathematical formulas? The answer might just lie in quantum cryptology or quantum key distribution, which uses photon modification to encode and transmit data. However, the technology has typically required gear only found in top laboratories. Both sender and recipient need to have a source of those photons, the equipment has to be perfectly aligned and the encryption tends to be highly susceptible to noise. Yet, Jeremy O'Brien and his physicist cohorts from the University of Bristol might have come upon a mobile-friendly solution. Their proposed method only requires the transmitting party to have the appropriate photon-sending equipment while the recipient needs just a simple device -- say, a phone -- to change them and send the information back. Called "reference frame independent quantum key distribution" or rfiQKD, the technique is robust enough to not rely on proper alignment and is apparently able to withstand a high level of noise as well. In a recent paper submitted to arXiv.org, O'Brien and his co-authors state that "the results significantly broaden the operating potential for QKD outside the laboratory and pave the way for quantum enhanced security for the general public with handheld mobile devices." While we're not sure if the method will solve all our security woes, it's certainly a start. If you feel you're able to grok the science, head on over to the source for more details on the team's findings.
USC finds that D-Wave's quantum computer is real, maybe
D-Wave has had little trouble lining up customers for its quantum computer, but questions have persisted as to whether or not the machine is performing quantum math in the first place. University of Southern California researchers have tested Lockheed Martin's unit to help settle that debate, and they believe that D-Wave's computer could be the real deal -- or rather, that it isn't obviously cheating. They've shown that the system isn't based on simulated annealing, which relies on traditional physics for number crunching. The device is at least "consistent" with true quantum annealing, although there's no proof that this is what's going on; it may be using other shortcuts. Whether or not D-Wave built a full-fledged quantum computer, the resulting output is credible enough that customers won't feel much in the way of buyer's remorse.
Quantum cryptography keys ride the lightning on existing fiber lines
Quantum computing has teased us with its potential for some time, but we won't be seeing qubits in our laptops anytime soon. However, science has also sought to leverage quantum physics in cryptography, and a recent breakthrough will allow for quantum encryption over fiber optic cables already in use. Researchers from Toshiba and Cambridge University discovered that they could transmit and receive encryption keys using pulses of quantum light and a specialized photodetector. The trick was to build a detector with a gate capable of both sensing a single photon and opening for just one tenth of one billionth of a second at the precise time that the photon arrives. Knowing the timing of the photon's arrival with such precision allows the quantum light to be captured and filtered out from other light pulses carrying regular data in the cable. Why all the effort to use quantum light? Well, if any quantum photon carrying an encryption key is intercepted during transmission, it's permanently changed. This, in turn, alerts those intended to receive the info that the encryption key may have been compromised. Previously, quantum encryption keys could be exchanged, but only if sent using a dedicated fiber line, which isn't a cost-effective solution. This new method allows keys to be sent via existing lines already in operation transmitting data, so no dedicated fiber need be installed. In testing, simultaneous 1 Mbps quantum key data rates and 1 Gbps regular data rates were achieved, and one researcher told BBC News that the technology is "not too far away" from being used to secure financial networks. For now, the new quantum key distribution method remains in the lab, but you can read all about it at the source below.
Alt-week 11.03.12: zombie animals, martian methane and self healing buildings
Alt-week peels back the covers on some of the more curious sci-tech stories from the last seven days. After a week where large numbers of people found themselves at the mercy of mother nature, many will be reminded just how vulnerable we really can be at times. That said, science still provides us with a pretty big stick to whack many other problems with. After the break we look at how crumbling buildings could soon be self-healing, why some UK-based scientists think they are one step closer to answering the "is light made of waves or particles" quandary, and NASA reveals its latest results in the hunt for martian methane. Oh, and there's some zombie animals too. This is alt-week.
Flawed diamonds are perfect ingredients for quantum computing, just add time travel
Ready to suspend your brain cells in a superposition of disbelief? Good, because the latest news published in Nature is that diamonds are a quantum computer's best friend -- particularly if they're flawed. An international team of scientists sought out sub-atomic impurities in a 1mm-thick fragment of over-priced carbon and used these as qubits to perform successful calculations. A "rogue" nitrogen nucleus provided one qubit, while a free electron became a second. Unlike previous attempts at solid-state quantum computing, this new effort used an extra technique to protect the system from decoherence errors: microwave pulses were fired at the electron qubit to "time-reverse" inconsistencies in its spinning motion. Don't fully get it? Us neither. In any case, it probably won't stop jewellers tut-tutting to themselves.
IBM: We're on the cusp of the Quantum Computing revolution (video)
Technology's holy grail is the development of a "perfect" Quantum Computer. Traditional computers recognize information as bits: binary information representing "On" or "Off" states. A quantum computer uses qubits: operating in superposition, a qubit exists in all states simultaneously -- not just "On" or "Off," but every possible state in-between. It would theoretically be able to instantly access every piece of information at the same time, meaning that a 250 qubit computer would contain more data than there are particles in the universe. IBM thinks it's closer than ever to realizing this dream and if you want to know more, we have the full details after the break.
Researchers use lasers to supercool semiconductor membranes, blow your mind
Ah, lasers. Those wonderful, super intense beams of light that we've seen used in headlights, projectors, and naturally, death rays. Like us, researchers at the Niels Bohr Institute at the University of Copenhagen figure there's nothing lasers can't do, and have figured out a way to use them to cool a bit of semiconducting material. This bit of black magic works using a membrane made of gallium arsenide and is based upon principles of quantum physics and optomechanics (the interaction between light and mechanical motion).Turns out, when a one millimeter square membrane of gallium arsenide is placed parallel to a mirror in a vacuum chamber and bombarded with a laser beam, an optical resonator is created between them that oscillates the membrane. As the distance between the gallium arsenide and the mirror changes, so do the membrane's oscillations. And, at a certain frequency, the membrane is cooled to minus 269 degrees Celsius -- despite the fact that the membrane itself is being heated by the laser. So, lasers can both heat things up and cool them down simultaneously, and if that confuses you as much as it does us, feel free to dig into the science behind this paradoxical bit of research at the source below. In other news, left is right, up is down, and Eli Manning is a beloved folk hero to all Bostonians.
First light wave quantum teleportation achieved, opens door to ultra fast data transmission
Mark this day, folks, because the brainiacs have finally made a breakthrough in quantum teleportation: a team of scientists from Australia and Japan have successfully transferred a complex set of quantum data in light form. You see, previously researchers had struggled with slow performance or loss of information, but with full transmission integrity achieved -- as in blocks of qubits being destroyed in one place but instantaneously resurrected in another, without affecting their superpositions -- we're now one huge step closer to secure, high-speed quantum communication. Needless to say, this will also be a big boost for the development of powerful quantum computing, and combine that with a more bedroom friendly version of the above teleporter, we'll eventually have ourselves the best LAN party ever.
Quantum batteries are theoretically awesome, practically non-existent
Today's dose of overly ambitious tech research comes from the physics lab over at the University of Illinois at Urbana-Champaign, in a proposal titled "Digital quantum batteries: Energy and information storage in nano vacuum tube arrays." It's like a who's who of undelivered promises got together and united to form one giant and impossible dream, but it's one we'd prefer to believe in regardless. Aiming to improve battery performance by "orders of magnitude," the project's fundamental premise is that when capacitors -- and we're talking billions of them -- are taken to a small enough scale and packed to within 10nm of one another, quantum effects act to prevent energy loss. The projected result is a wonderful world of rapid recharges and storage of up to ten times the energy current lithium-ion packs can hold, as well as the potential for data retention. The only problem? It would take a year just to build a prototype, meaning we can expect market availability somewhere between a score from now and just prior to the underworld morphing into an ice rink.
Danish scientists achieve advanced quantum teleportation
As you can imagine, here at Engadget, we love it when science fiction becomes more science and less fiction. With that in mind, we're pleased to pass along the news that Danish scientists at Copenhagen University have made a breakthrough in the wacky world of quantum teleportation by transporting quantum information over a distance of half a meter (1.6 feet). In order to achieve this, Dr. Eugene Polzik and his team shined a strong laser beam into a cloud of room-temperature cesium atoms that shared the same directional spin. As Scientific American reports: "The laser became entangled with the collective spin of the cloud, meaning that the quantum states of laser and gas shared the same amplitude but had opposite phases. The goal was to transfer, or teleport, the quantum state of a second light beam onto the cloud." (It should be noted that this process is more akin to duplication than actual teleportation, i.e. using this method on a human being would result in the formation of a doppelganger and not a magical Star Trek-like movement of matter). To achieve this goal, Polzik and other scientists added a second weaker laser pulse and split the two beams into separate branches in order to measure the difference between the quantum phases; through that measurement the scientists were then able to transfer the information of the spin state of the weak laser to the combination of the cesium atoms and the strong laser, without disturbing the quantum entanglement between the laser and the cesium. Umm, so the short of it is: one small step for a cesium atom, but one giant leap for quantum computing research and the advancement of teleportation theory.[Thanks, Josh H. and Eric M.]Read - ReutersRead - Scientific American
