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Chinese Physicists Achieve Quantum Teleportation Over 60 Miles
MrSeb writes "Chinese physicists are reporting that they've successfully teleported photonic qubits (quantum bits) over a distance of 97 kilometers (60mi). This means that quantum data has been transmitted from one point to another, without passing through the intervening space. It's important to note that the Chinese researchers haven't actually made a photon disappear and reappear 97 kilometers away; rather, they've used quantum entanglement to recreate the same qubit in a new location, with the same subatomic properties as the original qubit. The previous record for transmitting entangled qubits was 16 kilometers, performed by another Chinese team back in 2010 — and perhaps most excitingly, the researchers seem confident that their system will scale up from 97km to distances capable of reaching orbital satellites, at which point we'll actually be able to build a global quantum network for all of our cryptographic needs."
I hear the next step is transporting economic superpower status over 7,000 miles.
What political party do you join when you don't like Bible-thumpers *or* hippies?
Lord... Whats a qubit?
Don't blame me, I voted for Kodos
So....how long until we have an Ansible?
You can't transmit meaningful information with quantum teleportation alone, you still need a classical channel that operates by conventional means unless you want to transmit uncontrollable random garbage.
"When information is power, privacy is freedom" - Jah-Wren Ryel
Now we won't transfer our warez over any wires or IP numbers at all, and will just teleport the data all over the place.
Build your own energy sources from scratch. http://otherpower.com/
The information contained in the qbit is transported from one entangled photon to another, but you first must get that entangled photon to the destination via more conventional means. They're doing that with a laser.
So it's replication, not teleportation?
Twinstiq, game news
This is part of an international research effort, including schools like Carnegie-Mellon in the US. However, due to the lower costs of photonic qubits in China, it only makes sense to have the majority of experiments carried out over there.
So that means the satellite television providers will be all over this.
Note that it's still limited by the speed of light. The key feature, however, is that it is secure: someone intercepting the photon can't copy or read its qbit state without breaking the quantum entanglement, or preventing it from reaching the destination. In either case, the receiver will immediately know that the channel has been broken. It then stops transmitting a response to the sender, and the sender perceives this as also a break in secure communications and stops transmitting. Both the sender and the receiver would then go into failure mode and send query/response polls periodically. When secure communications are re-established, they can resume transmitting data.
If we have a 72-kg (158 lb.) person made mostly out of water, that's about 4,000 moles, or 2.4x10^27 molecules, which is about 7.2x10^27 atoms. The actual number might be different, but it's way more than a trillion.
Sigh. What happened to the days when nerds would read science fiction without believing that someday it would all be real?
When was that? My dad still complains about not having a flying car or being able to take a flight to the moon.
at which point we'll actually be able to build a global quantum network for all of our cryptographic needs.
Are you a member of the Chinese Army?
Have gnu, will travel.
Ah, but the abstract of the paper itself says "Over a 35-53 dB high-loss quantum channel, an average fidelity of 80.4(9) % is achieved for six distinct initial states." That sounds like a lossy channel to me. Plus, I simply don't believe it's possible to send a laser beam over X kilometers, including an atmosphere, and have them ALL reach their destination - it's a limitation of the medium.
Also, the Physics ArXiv blog post for this paper includes this;
"Inevitably photons get lost and entanglement is destroyed in such a process. Imperfections in the optics and air turbulence account for some of these losses but the biggest problem is beam widening (they did the experiment at an altitude of about 4000 metres). Since the beam spreads out as it travels, many of the photons simply miss the target altogether. "
and
"That's interesting because it's the same channel attenuation that you'd have to cope with when beaming photons to a satellite with, say, 20 centimetre optics orbiting at about 500 kilometres. "The successful quantum teleportation over such channel losses in combination with our high-frequency and high-accuracy [aiming] technique show the feasibility of satellite-based ultra-long-distance quantum teleportation," say Juan and co."
So it looks to me as though even the paper's author is admitting some "channel losses". The question I still have is, how is it possible to distinguish channel losses from adversarial interception of photons?
unfortunately this is beyond most 5th graders. any analogy for laymen will always fall short. analogies for those familiar with QM are tough enough as it is. but here's a classic bob and alice example: http://en.wikipedia.org/wiki/Quantum_teleportation#Motivation
insensitive clod overlords obligatory xkcd car analogy russian reversals whoosh pedant fanbois ftfy in 3...2...1..PROFIT
It shows a complete lack of understanding of science.
And of course the actual distance will have been 100km which someone who does understand significant figures converted to 60 miles for Americans. Followed by a moron deciding to convert it to 97 km because they are scientifically illiterate.
Hey, Friday is my day to post.
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ECHELON is a government program to find words like bomb, jihad, plutonium, assassinate, and anarchy.
He used the SI mole, which neither Americans or Europeans apparently understand.
Still waiting on Serviscope_minor to wake up to fucking reality and realize that Jessica Price isn't going to fuck him.
Its sad, how even among /. you find so many people clearly believing lots of blatant misconceptions about quantum physics. :/
I mean, shit is definitely complicated, took me awhile to wrap my head around. But don't make assumptions or draw conclusions until you understand something, is that so hard?
GCS/MU/P d- s:- a-- C++++$ UL++ P+ L++ E+ W++ N o K- w--- O M+ V- PS+++ PE Y+ PGP t+ 5- X R++ tv+ b++ DI++ D++ G+ e++ h-