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First Object Teleported From Earth To Orbit (technologyreview.com)
Researchers in China have teleported a photon from the ground to a satellite orbiting more than 500 kilometers above. From a report: Last year, a Long March 2D rocket took off from the Jiuquan Satellite Launch Centre in the Gobi Desert carrying a satellite called Micius, named after an ancient Chinese philosopher who died in 391 B.C. The rocket placed Micius in a Sun-synchronous orbit so that it passes over the same point on Earth at the same time each day. Micius is a highly sensitive photon receiver that can detect the quantum states of single photons fired from the ground. That's important because it should allow scientists to test the technological building blocks for various quantum feats such as entanglement, cryptography, and teleportation. Today, the Micius team announced the results of its first experiments. The team created the first satellite-to-ground quantum network, in the process smashing the record for the longest distance over which entanglement has been measured. And they've used this quantum network to teleport the first object from the ground to orbit. Teleportation has become a standard operation in quantum optics labs around the world. The technique relies on the strange phenomenon of entanglement. This occurs when two quantum objects, such as photons, form at the same instant and point in space and so share the same existence. In technical terms, they are described by the same wave function.
Outside of an arbitrary definition that says a photon is an object because we say so, a photon is most certainly not an "object" using any ordinary definition of the term or even a definition that the vast majority of physicists would use (i.e. than an "object" has mass, which photons most certainly don't have or else they would never be able to travel at light speed).
AntiFA: An abbreviation for Anti First Amendment.
...now, beam down my clothes.
in order to understand everything that was going on with the experiment. I wish the traditional media good luck in trying to translate all of that into an article for mass consumption.
Entanglement does not transfer information.
Every end has half a stick.
Funny, I was thinking that this was one of the better summaries that I've seen on Slashdot lately. No click-bait, all the pertinent facts, and covers a subject that's actually news for nerds. The summary is plenty good enough to not have to RTFA, which should be the top criterion for all good Slashdotters!
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If you are going to hype like this, why aim so low? Might as well tack on cure for cancer and solving world hunger.
sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
What it means is, that the quantum state from a particle on Site A is transferred to a particle on Site B. This involves an entangled state of two particles in A and B. Depending on the experimental set up the entangled particle in site B may be the object the quantum state is transferred to. The "teleportation" involves a measurement in Site A, and to completely transfer the quantum state to B one needs the (classical) result of this measurement at site B.
"By the way if anyone here is in advertising or marketing... kill yourself." -- Bill Hicks
No-Communication Theorem
In physics, the no-communication theorem is a no-go theorem from quantum information theory which states that, during measurement of an entangled quantum state, it is not possible for one observer, by making a measurement of a subsystem of the total state, to communicate information to another observer. The theorem is important because, in quantum mechanics, quantum entanglement is an effect by which certain widely separated events can be correlated in ways that suggest the possibility of instantaneous communication. The no-communication theorem gives conditions under which such transfer of information between two observers is impossible. These results can be applied to understand the so-called paradoxes in quantum mechanics, such as the EPR paradox, or violations of local realism obtained in tests of Bell's theorem. In these experiments, the no-communication theorem shows that failure of local realism does not lead to what could be referred to as "spooky communication at a distance" (in analogy with Einstein's labeling of quantum entanglement as "spooky action at a distance").
They pointed a flashlight at some satellite.
Troll is not a replacement for I disagree.
No not technically. Did particle A starting in position X end up at position Y? Was any information transferred or able to be transferred? Is faster than light communication possible? The answer to all these are no. Describing entanglement with teleportation is dumb.
https://en.wikipedia.org/wiki/...
https://xkcd.com/465/
Scientists: laypeople are twisting our words and making hyperbolic claims based on their misunderstanding of our research.
Other Scientists: Hey let's name this phenomenon after a fantastical and thematically similar yet completely unrelated concept in popular culture.
surely you mean:
Photon new_photon = new Photon(old_photon);
after all, we're trying to duplicate the properties.
the preceding comment is my own and in no way reflects the opinion of the Joint Chiefs of Staff
No not technically. Did particle A starting in position X end up at position Y? Was any information transferred or able to be transferred? Is faster than light communication possible? The answer to all these are no. Describing entanglement with teleportation is dumb.
https://en.wikipedia.org/wiki/...
Actually, quantum information was transferred. Of course there wasn't faster than light communication as quantum teleportation relies on entanglement *and* a classical communication channel.
For each qubit of information that wants to be sent, one of a pair of entangled photons needs to be conveyed to the destination (which can be done at nearly lightspeed for photons in free-space). After this is conveyance is done, then anytime later, a qubit from a third photon can be "teleported" to the destination by use of a conventional communication channel (which obviously isn't faster than light speed).
The way this works is you jointly measure the 3rd photon and your local singleton of the previously entangled photon which yields one of 4 joint states. This doesn't tell you the original state of the 3rd photon, only the joint state relative to the entangled photon, (but in the process collapses the state of these photons).
You then send this description of the measurement (basically two bits of information) across a classical channel to the destination (at whatever speed you want).
To replicate the quantum state at the destination, you manipulate the phase of the previously conveyed/entangled photon (without measuring it) according to on the results of the relative (2-bit) state description. After this manipulation, this previously conveyed entangled-photon has a non-collapsed replicated quantum state of the original 3rd photon, but the state was transmitted/teleported to its destination over a classical channel.
You can read the details from their paper paper. Over 32 days, they managed 911 four-photon events and achieved an estimated accuracy of about 80% of conveying the quantum state (the theoretical limit accuracy of a conventional channel was about 66% w/o using information obtained using measurements of previously conveyed entangled photons).
Remember you can't simply pre-measure a quantum state w/o collapsing it to determine the accuracy rate, so accuracy was determined statistically using two entangled pairs (which is why they needed to create a four-photon-event and for which it was hard to create a process for).
Baby steps.
Pretty sure there's a book or story about that..
There is a short story: Fat Farm, although that may just be ordinary biological cloning. I read it a long time ago.
It is also part of the plot of the movie The Prestige. The basic premise of this movie is that it you could teleport and create copies of yourself, rather than using that ability to acquire vast wealth and power, you would use it in a medicore magic show to duplicate what another act does using identical twins. That movie should win a Golden Raspberry for "most ridiculous premise".
How's life in the hypocrite lane?