Posted on 09/02/2017 8:30:41 PM PDT by TBP
In a massive step forward, researchers have sent the first quantum-secured message through the air above a city containing more than one bit of information. This proof-of-concept success means that high-capacity, free-space quantum communication will one day be both a practical and secure process between satellites and Earth—and a worldwide quantum encryption network will also be feasible.
In their demonstration, researchers used 4D quantum encryption to transmit data over a free-space optical network between two buildings. The buildings on the University of Ottawa campus stand 0.3 kilometers apart. The high-dimensional encryption scheme is described as “4D” because it sends more information, as every photon encodes two bits of information. This, in turn, means that each photon carries four possibilities with it: 00, 01, 10, or 11.
High-dimensional quantum encryption is also more secure because it can tolerate more signal-obscuring noise such as noise from failed electronics, turbulent air, malfunctioning detectors, and even interception attempts without rendering the transmission unsecured. “This higher noise threshold means that when 2D quantum encryption fails, you can try to implement 4D because it, in principle, is more secure and more noise resistant,” Ebrahim Karimi said in a news release.
Current algorithms are unlikely to be secure in the future as computers become more powerful. Therefore, researchers are working to master stronger encryption techniques such as light-harnessing quantum key distribution, which uses the quantum states of light particles to encode and send the decryption keys for encoded data.
REAL-WORLD TESTING
Now, the concept of quantum communications like this has been a theoretical concept until recently, because global implementation will demand transmission between Earth and satellites. Scientists have been using horizontal tests through the air over distances because the distortion that signals encounter can mimic what they might go through as they pass through the atmosphere. This successful demonstration proved that successful encryption is possible, despite distortion.
These researchers ported their optical setups from the lab to two different rooftops for the testing and protected them from the elements with wooden boxes. After some trial and error, the team successfully used this intracity link to send secure messages using 4D quantum encryption. The error rate for the messages was 11 percent, well below the 19 percent secure connection threshold. The team also compared 4D and 2D encryption, and they found that they were able to transmit 1.6 times more data per photon after error correction using 4D quantum encryption, in spite of turbulence.
Next, this research team plans to test the technology in a three-link network that spans longer distances, with each link about 5.6 kilometers apart. They will also use adaptive optics technology to compensate for the turbulence. The long-term goal is to link the network to the existing city network, creating “a quantum communication network with multiple links but using more than four dimensions while trying to get around the turbulence,” graduate student and team member Alicia Sit said in the press release.
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I’ve been saying the exact same thing for years & nobody wrote an article about it.
It seems to me that this would allow nearly instantaneous communication anywhere in the solar system.
It takes a radio signal anywhere from 4 minutes to 24 minutes to travel from Mars to Earth, depending on the relative positions of the two planets at any given time in their orbits.
And Mars is the closest planet to Earth.
but first you have to transport one there
It’s well established that when two electrons are entangled, no matter how far away they are moved, they “communicate” instantaneously. Change the spin of one, and the spin of the other instantly changes.
This is nice but nothing is secure with Hillary around.
This should allow E.T. to phone home much more expediently.
Yes, that's the catch.
Perhaps a completed functioning method fully realized what with probes launched from the past.
Send one down a worm hole to another galaxy.
I believe each particle is at two places at the same time, or, alternatively, has a double. Do something to its double kight years away and it will be immediately affected.
Only if you can control the states on one end, which is apparently not possible.
I think the only thing you can do is observe it.
Actually Venus is only half the distance.
but it would allow for immediate communications along the trip
First question: How do we find two electrons that are entangled ?
Second question: If 'spin' is the determiner of entanglement, isn't there a 50/50 chance that any electron selected will match the spin of another ?
Third question: In determining whether electrons are entangled, we have to determine what 'spin' they have. Doing so causes them to change 'spin' (an assumption). How do we know it changes when we don't know what 'spin' it had until we try to determine what 'spin' it has ?
How do we find those two specific particles out of an infinity of particles that exist ? Are they labeled ?
How do we know for sure that only two particles are 'linked' ? Maybe when we change the 'spin' of one particle (which can't be determined for sure but is an assumption because we don't know what it's spin 'was') it changes the spin of HALF the particles in the Universe.
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