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Post by swamprat on Sept 22, 2015 12:39:16 GMT -6
Well, maybe not quite yet......
Shades of 'Star Trek'? Quantum Teleportation Sets Distance Recordby Charles Q. Choi, Live Science Contributor September 22, 2015
A record-breaking distance has been achieved in the bizarre world of quantum teleportation, scientists say.
The scientists teleported photons (packets of light) across a spool of fiber optics 63 miles (102 kilometers) long, four times farther than the previous record. This research could one day lead to a "quantum Internet" that offers next-generation encryption, the scientists said.
Teleporting an object from one point in the universe to another without it moving through the space in between may sound like science fiction pulled from an episode of "Star Trek," but scientists have actually been experimenting with "quantum teleportation" since 1998.
Quantum teleportation depends on capturing the fundamental details of an object — its "quantum states" — and instantly transmitting that information from one area to another to recreate the exact object someplace else.
Quantum teleportation relies on the strange nature of quantum physics, which finds that the fundamental building blocks of the universe can essentially exist in two or more places at once.
Specifically, quantum teleportation relies on an odd phenomenon known as "quantum entanglement," in which subatomic particles can become linked and influence each other instantaneously, regardless of how far apart they are. Scientists cannot distinguish the state of either particle until one is directly measured, but because the particles are connected, measuring one instantly determines the state of the other.
Currently, physicists can't instantly transport matter (say, a human), but they can use quantum teleportation to beam information from one place to another. In a recent experiment, scientists at the National Institute of Standards and Technology (NIST) were able to teleport photons farther across an optical fiber than ever before.
"What's exciting is that we were able to carry out quantum teleportation over such a long distance," study co-author Martin Stevens, a quantum optics researcher at the NIST in Boulder, Colorado, told Live Science.
The new distance record was set using advanced single-photon detectors made of superconducting wires of molybdenum silicide that were about 150 nanometers (or billionths of a meter) wide and cooled to about minus 457 degrees Fahrenheit (minus 272 degrees Celsius), or about 1 degree above absolute zero. The experiment involved a near-infrared wavelength commonly used in telecommunications, the researchers said.
Only about 1% of photons make it all the way through 100 kilometers (60 miles) of fiber," Stevens said in a statement. "We never could have done this experiment without these new detectors, which can measure this incredibly weak signal."
The detectors used in this new experiment could record more than 80 percent of arriving photons, according to the scientists. In comparison, the previous record-holder had detectors that operated with about 75 percent efficiency at best. Moreover, the new experiment detected 10 times fewer stray photons than the previous record-holder.
Prior research did achieve quantum teleportation over longer distances over open air — a span of 89 miles (144 kilometers) between the two Canary Islands of La Palma and Tenerife, located off the northwest coast of Africa.
"However, the experiment at the Canary Islands involved a telescope on top of one mountain and a telescope on top of another mountain, with the telescopes pointed at each other at night, since background light during the day would interfere with the experiment," Stevens said. "If you wanted quantum teleportation in the real world — say, from one city to another — you might not necessarily have a direct line-of-sight between two locations, and you wouldn't want to be limited to working at night, so fiber optics might be more feasible."
Quantum teleportation could enable the development of a "quantum Internet" that allows messages to be sent more securely, Stevens said.
"A quantum Internet could allow you to establish communications channels that are much more secure than what we have with the standard encryption protocols we use everyday nowadays," Stevens said.
The researchers now plan to develop even better single-photon detectors to push distances for quantum teleportation even farther, Stevens said.
The scientists detailed their findings online today (Sept. 22) in the journal Optica.
www.livescience.com/52259-quantum-teleportation-sets-distance-record.html
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Post by Deleted on Sept 27, 2015 14:50:21 GMT -6
and cooled to about minus 457 degrees Fahrenheit (minus 272 degrees Celsius), or about 1 degree above absolute zero. The experiment involved a near-infrared wavelength commonly used in telecommunications, the researchers said. Read more: theedgeofreality.proboards.com/thread/6023/beam-energize#ixzz3mySwEfWv_______________________________________________________________________________________ Hmmmmmmmmmmmmmmmmmmmmmm. And just how is that temperature maintained?
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Post by swamprat on Sept 27, 2015 19:57:59 GMT -6
JC, I'm not sure what they did, but there are a couple of ways to do it. Liquid He4 has a boiling temperature of 4.2 K. If you pump on that and reduce the vapor pressure, you get evaporative cooling that lowers the temperature to 1.8 K. If you use liquid He3 instead, you can reach a lower temperature of 300 mK or 0.3 K. And, if you mix liquid He4 and liquid He3, in something called a dilution refrigerator, you can get down to 25 mK, or 0.025 K.
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Post by patsbox7 on Oct 1, 2015 20:22:10 GMT -6
So it states that "scientists CAN use quantum teleportation to transmit information". So is this saying that they can use entanglement to send information, or is that different? If so, this is news to me as it would mean relativity is officially disproven.
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Post by Deleted on Oct 5, 2015 8:50:14 GMT -6
JC, I'm not sure what they did, but there are a couple of ways to do it. Liquid He4 has a boiling temperature of 4.2 K. If you pump on that and reduce the vapor pressure, you get evaporative cooling that lowers the temperature to 1.8 K. If you use liquid He3 instead, you can reach a lower temperature of 300 mK or 0.3 K. And, if you mix liquid He4 and liquid He3, in something called a dilution refrigerator, you can get down to 25 mK, or 0.025 K. Thanks Swampster! It just makes sense that this "process" is going to be easier doing it through Space, like it was represented on Star Trek. It still gives me "chills". If they have to send parts of me down a line, or along a laser beam, I'd rather be traveling through "the open", than under the earth through some cable or whatnot!
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Post by swamprat on Jul 11, 2017 14:01:34 GMT -6
Another Success for Them; Another Headache for Me Space breakthrough: Scientists teleport photon from Earth to orbit Published July 11, 2017
For the first time, scientists have successfully teleported a photon from the ground to a satellite in orbit.
It’s been 20 years since quantum scientists successfully teleported a photon over 10 miles, proving that quantum entanglement — a process that Albert Einstein called “spooky action at a distance” -- was possible.
The very unnatural phenomenon occurs when two quantum objects, such as photons, share a wave function. Since they come into existence at the exact same time and place, they share the same identity, even when separated. What happens to one happens to the other — wherever it exists.
In 2010, a team at the University of Science and Technology of China in Shanghai set a record by teleporting photons over 60 miles on Earth.
And now, just seven years later, they’ve outdone themselves, teleporting protons from a ground station in Tibet, 2½ miles above sea level, to a satellite orbiting Earth more than 310 miles away.
It marks the first time an object has been teleported from our planet into space.
Last year, China launched a research satellite called Micius into a sun-synchronous orbit, meaning it passes over the same point on Earth at the same time every day. Chinese scientists then created thousands of entangled pairs of photons and beamed one photon from each pair to Micius. After measuring both photons, they confirmed that 911 on Micius remained entangled with their companions on Earth.
They’re more than identical twins. The two are one and the same.
And, theoretically, the sky isn’t the limit. Photons are fragile; when they interact with matter on Earth and in Earth’s atmosphere, they lose entanglement. But in the vacuum of space, they can extend infinitely.
And while the process won’t exactly succeed in making Captain Kirk demolecularize on the Starship Enterprise and remolecularize on a planet below, it has the potential nonetheless to change the world as we know it. Quantum teleportation is seen as the basis for unimaginably high-speed communication and foolproof cryptography. Since the two objects are not twins but actually the same object, what happens to one happens instantaneously to the other.
Beam that up, Scottie.
www.foxnews.com/tech/2017/07/11/space-breakthrough-scientists-teleport-photon-from-earth-to-orbit.html
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Post by swamprat on Jul 15, 2017 15:23:38 GMT -6
Here is a little more detail..... Photon Teleported Between Earth and Space for the First TimeBy Ryan Whitwam July 10, 2017
Quantum entanglement is one of the most counter-intuitive and perplexing effects in modern physics. Two objects can be separated by great distances, yet they share the same quantum states. Famed physicist Albert Einstein once described the process of affecting an object in this way as “spooky action at a distance,” and a team of Chinese scientists just took spooky into space. For the first time, quantum “teleportation” has been demonstrated between Earth and an object in space.
The curious thing about entanglement is that this shared existence continues even when the photons are separated by vast distances. So a measurement on one immediately influences the state of the other, regardless of the distance between them.
Back in the 1990s, scientists realized they could use this link to transmit quantum information from one point in the universe to another. The idea is to “download” all the information associated with one photon in one place and transmit it over an entangled link to another photon in another place.
This second photon then takes on the identity of the first. To all intents and purposes, it becomes the first photon. That’s the nature of teleportation and it has been performed many times in labs on Earth.
China launched its Micius research satellite last year to study the limits of quantum entanglement. The Long March 2D rocket deposited its payload in Sun-synchronous orbit, meaning it passes over the same point on Earth at the same time each day. This allows the team to plan this carefully timed research, which relies upon the highly sensitive photon receiver on the Micius satellite. It’s able to detect the quantum states of single photons projected from the ground.
Researchers have announced the successful communication of quantum information between the ground station and Micius, which is anywhere from 500 and 1,400 kilometers (310-870 miles) above the surface, breaking the distance record for quantum entanglement. This is not teleportation in the Star Trek sense, but quantum teleportation is often cited as a potential basis for high-speed communication and uncrackable cryptography. Basically, when two objects become entangled, they share the same quantum state. From a physics perspective, they’re the same object. The entanglement remains even when the objects are separated by great distances. Thus, changes to one object are immediately replicated by the other.
This sort of teleportation has been accomplished in laboratories on Earth, but the record for distance was around 100 km (62 miles). The problem is that two objects (photons in this case) will only remain entangled if they don’t interact too much with other objects. The atmosphere and fiber optic cables used in experiments will eventually break the bond between two entangled objects. However, it’s easier to control for that in space.
Most of the transmission distance is in a vacuum, where the photos don’t interact with anything that could break the link. The team worked to lessen the chance photos would be disrupted by building the ground station at an altitude of 4,000 feet in Tibet. The team created entangled pairs of photos at a rate of 4,000 per second, then beamed then beamed half of the pair to Micius. Measurements carried out on the ground and orbiting photos shows that some of them were indeed still entangled.
This process is far from perfect, though. Out of millions of photons sent up to Micius, only 911 of them remained entangled with the ones on the ground. That’s still an impressive result, and one that could help us better understand this spooky action.
www.extremetech.com/extreme/252140-chinese-satellite-smashes-quantum-teleportation-distance-record
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Post by swamprat on Jul 20, 2017 12:21:00 GMT -6
Quantum teleportation is even weirder than you thinkDon't let the catchy name distract you, says Philip Ball: the questions inspired by this arguably misnamed phenomenon go to the heart of quantum theory.
by Richard Haughton 20 July 2017 A BBC headline last week, ‘First object teleported to Earth’s orbit’, has to be one of the most fantastical you’ll see this year. For once, it seems the future that science fiction promised has arrived! Or has it?
The article was talking about reports by Chinese scientists that they had transmitted the quantum state of a photon on Earth to another photon on a satellite in low Earth orbit, some 1,400 kilometres away. That kind of transmission — first demonstrated in a laboratory 20 years ago — is known as quantum teleportation. It’s a label that can mislead the unwary, as the BBC headline demonstrates. A write-up of the work in Discover reports that the scientists “have successfully transmitted quantum entangled particles” — only to clarify, confusingly, that “unlike science fiction teleportation devices, nothing physical is being transported”.
But wait: didn’t someone once say information is physical? That was physicist Rolf Landauer3, a pioneer of information theory. So if you send nothing physical, how can you transmit anything at all from A to B?
This is one of the deep issues that quantum physicists and philosophers still argue about. We can debate whether ‘quantum teleportation’ as a term is a catchy way of conveying a scientific idea, or a misleading bit of hype. But the real question — what, exactly, is transmitted during quantum teleportation, and how — touches on issues much more profound.
Quantum telepheresis If physicists Asher Peres and William Wootters had stuck to calling this quantum process ‘telepheresis’ when they first conceived of it in 1993, I doubt we’d be seeing headlines about it today. It was their co-author Charles Bennett who suggested instead ‘quantum teleportation’.
Whatever it’s called, the process transfers the quantum state of one particle onto another, identical particle, and at the same time erases the state in the original. This situation can’t be meaningfully distinguished from one in which the original particle itself has been moved to the target location: that transport has not really happened, but to all appearances it might as well have.
Crucially, however, this works only if you do not know what ‘information’ you are sending — that is, what the quantum state of the original particle actually is.
Teleportation of a quantum state uses the phenomenon of quantum entanglement as a means of transmission. When two or more particles are entangled, their quantum states are interdependent, no matter how far apart they are. In effect, they act as a single quantum object, described by a single wavefunction — the mathematical construct that encodes all the quantum properties of the object.
The procedure begins by entangling a pair of particles to set up the quantum transmission channel. Particle A is held by the sender — call her Alice — and B is sent to the receiver, Bob. Because the particles are entangled and thus interdependent, if Alice performs a physical operation on hers, that can be instantaneously reflected in the state of Bob’s. Alice also has another particle C: one whose quantum state she does not know, but wants to teleport onto B.
To perform the teleportation, Alice makes a special kind of measurement, called a Bell measurement, on particles A and C together. Crucially, this doesn’t tell her what state C is in. But because of the entanglement between A and B, it places B in a state that can be turned into whatever state C originally had, if Bob applies the right operation. By making her measurement, however, Alice has erased that state from C itself.
But what is the operation Bob needs to apply to complete the teleportation? He can deduce that from the outcome of Alice’s Bell measurement. She has to communicate that outcome to him by some classical means — e-mail, phone, carrier pigeon, whatever works. Once he gets it, Bob knows what to do to turn B into a form identical to the original C.
Copying forbidden A common view is that quantum teleportation is a new way of transmitting information: a kind of high-speed quantum Wi-Fi. What’s amazing about it is that the quantum ‘information’ is ‘sent’ instantaneously — faster than light — because that is how two entangled particles communicate.
But isn't that supposed to be forbidden by Albert Einstein’s special theory of relativity. Yes — and that problem lay at the root of Einstein’s objections to the standard interpretation of what quantum entanglement entailed (he dubbed it “spooky action at a distance”). What special relativity actually prohibits is faster-than-light causal influence: an event in one place can’t have a physical, observable effect at another place in less time than it takes for light to travel between the sites. Quantum teleportation does not transmit any faster-than-light causal influence, because you also need the classical channel — limited to light speed at best — to complete the process.
It’s crucial that the teleported state is never measured directly. Keeping this information ‘hidden’ during the entanglement-enabled teleportation, and destroying it in the original in order to send it to the target, ensures that there is never a duplicate. The process thereby observes a fundamental principle in quantum mechanics, called no-cloning: it is impossible to make a copy of an arbitrary (unknown) quantum state.
That prohibition causes problems related to handling errors in quantum computing, but also enables the technology called quantum cryptography, which makes it impossible to eavesdrop on a message encoded in quantum states without being detected.
No-cloning is more than a technical complication of quantum information technology. Some researchers suspect that rather than being a consequence of the rules of quantum mechanics, it is in fact one of the deep principles — almost a fundamental axiom — that result in counter-intuitive quantum phenomena such as entanglement in the first place.
What is information? So what exactly is being transmitted through entanglement alone?
This is a tricky question for quantum information theory in general: it is not obvious what ‘information’ means here. As with other colloquial words adopted by science, it is too easy to imagine we all know what we’re talking about. The 'stuff' transmitted by entanglement is neither information in the sense of Claude Shannon’s information theory (where it is quantified in terms of entropy, increasing as the 'message' gets more random), nor in the sense of an office memo (where information becomes meaningful only in the right context). Then what is it information about, exactly?
That issue, at the heart of quantum information theory, has not been resolved. Is it, for example, information about some underlying reality, or about the effects of our intervention in it? Information universal to all observers, or personal to each? And can it be meaningful to speak of quantum information as something that flows, like liquid in a pipe, from place to place? No one knows (despite what they might tell you). If we can answer these questions, we might be close finally to grasping what quantum mechanics means.
So the real marvel of what we call quantum teleportation is not so much what we can do with it as a technology, but what it reveals about the deep quantum structure of the world.
www.nature.com/news/quantum-teleportation-is-even-weirder-than-you-think-1.22321?WT.ec_id=NEWSDAILY-20170719
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