Scientists in the Netherlands have moved a step closer to overriding one of Albert Einstein’s most famous objections to the implications of quantum mechanics, which he described as “spooky action at a distance.”
In a paper published on Thursday in the journal Science, physicists at the Kavli Institute of Nanoscience at the Delft University of Technology reported that they were able to reliably teleport information between two quantum bits separated by three meters, or about 10 feet.
Quantum teleportation is not the “Star Trek”-style movement of people or things; rather, it involves transferring so-called quantum information – in this case what is known as the spin state of an electron – from one place to another without moving the physical matter to which the information is attached.
Classical bits, the basic units of information in computing, can have only one of two values – either 0 or 1. But quantum bits, or qubits, can simultaneously describe many values. They hold out both the possibility of a new generation of faster computing systems and the ability to create completely secure communication networks.
A forest of optical elements that was part of the quantum teleportation device used by the team of physicists in the Netherlands. Credit Hanson lab@TUDelft
Moreover, the scientists are now closer to definitively proving Einstein wrong in his early disbelief in the notion of entanglement, in which particles separated by light-years can still appear to remain connected, with the state of one particle instantaneously affecting the state of another.
They report that they have achieved perfectly accurate teleportation of quantum information over short distances. They are now seeking to repeat their experiment over the distance of more than a kilometer. If they are able to repeatedly show that entanglement works at this distance, it will be a definitive demonstration of the entanglement phenomenon and quantum mechanical theory.
Succeeding at greater distances will offer an affirmative solution to a thought experiment known as Bell’s theorem, proposed in 1964 by the Irish physicist John Stewart Bell as a method for determining whether particles connected via quantum entanglement communicate information faster than the speed of light.
“There is a big race going on between five or six groups to prove Einstein wrong,” said Ronald Hanson, a physicist who leads the group at Delft. “There is one very big fish.”
In the past, scientists have made halting gains in teleporting quantum information, a feat that is achieved by forcing physically separated quantum bits into an entangled state.
Researchers teleported quantum information between two distant atoms for the first time in 2009.
Click on image below to open interactive graphic
But reliability of quantum teleportation has been elusive. For example, in 2009, University of Maryland physicists demonstrated the transfer of quantum information, but only one of every 100 million attempts succeeded, meaning that transferring a single bit of quantum information required roughly 10 minutes.
In contrast, the scientists at Delft have achieved the ability “deterministically,” meaning they can now teleport the quantum state of two entangled electrons accurately 100 percent of the time.
They did so by producing qubits using electrons trapped in diamonds at extremely low temperatures. According to Dr. Hanson, the diamonds effectively create “miniprisons” in which the electrons were held. The researchers were able to establish a spin, or value, for electrons, and then read the value reliably.
In addition to the possibility of an impregnable quantum Internet, the research holds out the possibility of networks of quantum computers.
To date, practical quantum computers, which could solve certain classes of problems far more quickly than even the most powerful computers now in use, remain a distant goal. A functional quantum computer would need to entangle a large number of qubits and maintain that entangled state for relatively long periods, something that has so far not been achieved.
A distributed quantum network might also offer new forms of privacy, Dr. Hanson suggested. Such a network would make it possible for a remote user to perform a quantum calculation on a server, while at the same time making it impossible for the operator of the server to determine the nature of the calculation.
Four men paralyzed after bad spinal cord injuries can all move their legs again, thanks to an electrical stimulator.
Astonished researchers say they’d hoped for some result, but nothing like what they got. They think the stimulator is retraining the mens’ nerves to work with the brain again, despite the terrible damage.
“This is wonderful news. Spinal cord injury need no longer be a lifelong sentence of paralysis,” said Dr. Roderic Pettigrew, director of the National Institute of Biomedical Imaging and Bioengineering, one of the National Institutes of Health. “It is just downright marvelous.”
Rob Summers, now 28, was the first patient implanted and his case made international headlines in 2011 when he was first able to stand using the stimulator. Summers now exercises for three hours a day and says his life has been transformed.
“It has changed my life on a day-to-day basis,” said Summers, who was paralyzed from the chest down after a hit-and-run driver plowed into him as he stood in his own driveway. “It’s given me the ability to travel alone and come and go as I please.”
Summers says he does an hour of abdominal exercises daily, reversing the gradual wasting of muscles that normally comes with paralysis.
“I can now feel soft touch, hard touch. I can feel pinpricks,” Summers, who lives in Portland, Ore., told NBC News. “I can feel the wind on my legs.”
None of the four men can walk again, but researchers believe the stimulator is retraining the damaged nerves in their spinal columns to communicate once again with the brain. They’re not sure why – it may be some connection remained after their injuries or it is slightly possible the nerves are re-growing.
“We have uncovered a fundamentally new intervention strategy that can dramatically affect recovery of voluntary movement in individuals with complete paralysis even years after injury,” the researchers, led by Dr. Susan Harkema of the Frazier Rehabilitation Institute and the University of Louisville, write in their report, published in the journal Brain on Tuesday.
Because all four men tested have regained movement, including two who were completely paralyzed, it’s likely that many people who believed they were permanently paralyzed may be able to move again, says Reggie Edgerton, distinguished professor of integrative biology and physiology at the University of California, Los Angeles, who developed the approach.
“It tells us that the information from the brain is getting to the right place in the spinal cord, so that the person can control, with fairly impressive accuracy, the nature of the movement,” said Edgerton. “We don’t have to necessarily rely on regrowth of nerves in order to regain function. The fact that we’ve observed this in all four patients suggests that this is actually a common phenomenon in those with complete paralysis.”
The stimulator was originally developed by Medtronic to treat chronic pain. It’s a pacemaker-sized device implanted under the skin of the abdomen, connecting to electrodes placed near the spinal cord. When turned on, it delivers a low pulse of electricity.
For patients with chronic pain, the electricity interrupts the pain signal before it can reach the brain. The researchers adapted it to try on patients with paralysis.
“The next generation will be more precisely controlled and noninvasive,” says NIBIB’s Pettigrew, whose institute helped pay for the research, along with the Christopher & Dana Reeve Foundation.
Pettigrew says the results are no flash breakthough. They are based on decades of work. He says researchers are already working with a fresh batch of volunteers and will report new findings soon.
“It is why we come to work every day,” Pettigrew said.
The next step is to try and make the approach work without having to implant electrodes, Pettigrew said. The hope would be for an external device, with electrodes simply stuck onto the skin to stimulate the nerves.
“The implications of this study for the entire field are quite profound and we can now envision a day where epidural stimulation might be part of a cocktail of therapies used to treat paralysis,” said Susan Howley, executive vice president for research at the Christopher & Dana Reeve Foundation.
The accident cost Summers a promising possible career in baseball. He’d been a top pitcher for Oregon State University and he was struck a month after his team won the college world series.
But he’s happy now that going out to dinner is no longer an ordeal that required hours of preparation. He’s strong enough now to hop into his wheelchair and just go.
“Not only has this benefited me with the confidence to go out and do what I want to do… I can continue to live my life as I choose and not be restricted or limited,” Summers said. His doctors say he has regained continence, sexual function and even the lost ability to sweat.
“I truly believe this is the greatest thing out there,” Summers said.
Summers says he can feel the device working. “The best way to describe it is like a strong tingling sensation,” he says, almost like a limb feels after it’s “fallen asleep.” “It almost feels like pins and needles.”
The three other men whose cases are described in the report are all in their 20s and 30s now and, like Summers, had been paralyzed for years before trying the device.
Kent Stephenson of Mount Pleasant, Texas, was 21 when he was paralyzed in a motocross accident in 2009. He cannot move his leg without the stimulator, but with it on can pull his leg up to his chest, straighten it, and slowly lower it again.
Andrew Meas of Louisville was injured when his motorcycle and a car collided in 2007, while Dustin Shillcox of Green River, Wyo. was 26 when a company van he was driving blew out a tire and wrecked. Stephenson and Meas both have resumed outdoor activities such as snow machining and fishing.
Each has a little different level of function with the device. “I have mentored all the other guys using it,” Summers says. “We have been like a brotherhood bonding on this.”
The US Navy has developed a radical new fuel made from seawater.
They say it could change the way we produce fuel – and allow warships to stay at sea for years at a time.
Navy scientists have spent several years developing the process to take seawater and use it as fuel, and have now used the ‘game changing’ fuel to power a radio controlled plane in the first test.
The development of a liquid hydrocarbon fuel is being hailed as ‘a game-changer’ because it would allow warships to remain at sea for far longer.
The US has a fleet of 15 military oil tankers, and only aircraft carriers and some submarines are equipped with nuclear propulsion.
All other vessels must frequently abandon their mission for a few hours to navigate in parallel with the tanker, a delicate operation, especially in bad weather.
The ultimate goal is to eventually get away from the dependence on oil altogether, which would also mean the navy is no longer hostage to potential shortages of oil or fluctuations in its cost.
The predicted cost of jet fuel using these technologies is in the range of $3-$6 per gallon, and with sufficient funding and partnerships, this approach could be commercially viable within the next seven to ten years.
Pursuing remote land-based options would be the first step towards a future sea-based solution, the Navy says.
Vice Admiral Philip Cullom declared: ‘It’s a huge milestone for us.
‘We are in very challenging times where we really do have to think in pretty innovative ways to look at how we create energy, how we value energy and how we consume it.
‘We need to challenge the results of the assumptions that are the result of the last six decades of constant access to cheap, unlimited amounts of fuel,’ added Cullom.
‘Basically, we’ve treated energy like air, something that’s always there and that we don’t worry about too much.
‘But the reality is that we do have to worry about it.’
They hope the fuel will not only be able to power ships, but also planes.
The predicted cost of jet fuel using the technology is in the range of three to six dollars per gallon, say experts at the US Naval Research Laboratory, who have already flown a model airplane with fuel produced from seawater.
Dr Heather Willauer, an research chemist who has spent nearly a decade on the project, said:
‘For the first time we’ve been able to develop a technology to get CO2 and hydrogen from seawater simultaneously, that’s a big breakthrough,’ she said, adding that the fuel ‘doesn’t look or smell very different.’
Now that they have demonstrated it can work, the next step is to produce it in industrial quantities.
But before that, in partnership with several universities, the experts want to improve the amount of CO2 and hydrogen they can capture.
‘We’ve demonstrated the feasibility, we want to improve the process efficiency,’ explained Willauer.
Collum is just as excited.
‘For us in the military, in the Navy, we have some pretty unusual and different kinds of challenges,’ he said.
‘We don’t necessarily go to a gas station to get our fuel, our gas station comes to us in terms of an oiler, a replenishment ship.
‘Developing a game-changing technology like this, seawater to fuel, really is something that reinvents a lot of the way we can do business when you think about logistics, readiness.’
A crucial benefit, says Collum, is that the fuel can be used in the same engines already fitted in ships and aircraft.
‘If you don’t want to reeengineer every ship, every type of engine, every aircraft, that’s why we need what we call drop-in replacement fuels that look, smell and essentially are the same as any kind of petroleum-based fuels.’
Drawbacks? Only one, it seems: researchers warn it will be at least a decade before US ships are able to produce their own fuel on board.
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As you probably know, President Obama announced his decision to end NASA’s space shuttle program Constellation back in 2010. Since then, the US has been paying to transport astronauts to the ISS aboard Russian Soyuz capsules. NASA designed the four-person Space Launch System, a heavy launch vehicle, to replace the retired shuttles. So I’ve just been waiting patiently for that to come to fruition, somehow unaware of the Dream Chaser spacecraft, a commercial spaceflight transport system that will be able to take a crew of seven astronauts to the ISS, despite being about 1/3rd the size of a conventional shuttle.
The Dream Chaser will ride aboard an Atlas 5 rocket, which will propel the craft into low Earth orbit, potentially ferrying astronauts to the ISS. Service – or some kind of crewed mission – is expected to begin in 2017, with the first orbital crewless flight in late 2016. Dream Chaser’s first unmanned flight occurred in 2013, when it flew successfully but crashed due to a malfunction in its landing gear. Actually, the vehicle flipped over at the very end, coming to rest in an upright position, after which the malfunctioning left landing gear deployed. I like a spacecraft with a sense of humor. Despite the rocky ending, the flight was regarded as an overall success.
Dream Chaser was built by the Sierra Nevada Corporation, and it’s one of three potential commercial transport systems that are part of the space agency’s Commercial Crew Development process. NASA is expected to choose one or two of the these systems to take astronauts to the ISS. SpaceX’s Dragon is one, and Boeing’s CST-100 is the other, and so far all three have met target milestones. The teams are vying for the privilege of becoming NASA’s main mode of near-Earth orbit transit, kicking off the era of private commercial spaceflight for both crews and cargo.
That shift will also usher in another change, with the privatization of spaceflight beyond near-Earth orbit, to places such as Mars and asteroids. SpaceX, after all, is planning on taking people to colonize the Red Planet, but let’s not get ahead of ourselves, there are still more milestones to meet, and lots of fun to be had watching it happen.