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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.
peekaboo is not teleportation?
...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
How do they know it's the same photon?
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").
The business of high speed trades is finding the shortest distance between the trader's server and the stock exchange server, as detailed in "Flash Boys: A Wall Street Revolt" by Michael Lewis. Beaming packets of data into the stock exchange server is probably no faster than having your server 1U above/below the stock exchange server in the rack.
Except for that whole 'teleported' word.
That's how the can do free shipping on everything!
Technically, teleported is the correct word. We're talking teleportation in the scientific sense, not Star Trek teleportation -- not that the unwashed masses know the difference.
I'd actually say that "object" is the wrong word. I'm not sure I'd call a photon an object. "Particle" would be 1000% better, and much less confusing.
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Well, you have to admit that "Qian, beam me up!" doesn't sound nearly as good.
Ezekiel 23:20
Whoever invented the term "quantum teleportation" should be sentenced to prison life. Photons are NOT "teleported", what is "teleported" is the state of the physical system they represent (and this happens through classical communication, so no faster-than-light effects, EVER).
This is a big misunderstanding in popular science regarding the effects of quantum entanglement. You cannot use quantum entanglement to "teleport" information, nor matter.
At most, what could be *very hypothetically* conceivable is a scenario like:
1) you create on Earth two identical vats containing a large mass of "entangled matter", whatever it means
2) you move one of the vats on Mars, this has be done CLASSICALLY (i.e., rockets or similar)
3) then, on Earth, you enter a ridiculously complex chamber device, which annihilates simultaneously you and the vat, producing a large stream of data
4) this data is transmitted (i.e., antenna link) on Mars, where it is received by another, even more ridiculously complex device
5) this device acts on the vat on Mars, the vat is destroyed but not before you emerge from the vat.
This is as much realistic science-fiction can go. Source: I am a quantum information scientist.
I decline every responsibility in the case that it is not really *you* emerging from the Martian vat, but another cosmically malignant entity.
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/...
Great. Now I'm going to have to listen to my elderly father go on (again) about how we've invented the Ansible.
hmm i ment in the way of replacing something like this
Teleporting over long distances would still have to be faster than having a server in the same rack as the stock exchange server.
https://xkcd.com/465/
As documented in the historical documents, PANTS will be OBSOLETE in the 24th century.
.sig...
yow, that sounds like an absolute Zippyism
also, someone please quote me on that in their
the preceding comment is my own and in no way reflects the opinion of the Joint Chiefs of Staff
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.
Do you even think, creimer?
Can you educate yourself or do you need a box of crayons?
On a physical, financial exchange level, generally when you're talking about high-frequency trading you're talking about high-end servers such as HPG8s sitting in a rack, collocated at exchanges with a physical cross connect from the exchange into your rack. With that physical cross connect you can "order from a menu," Lauer says. "If you want a gigabit Ethernet, it costs you X. If you want 10-gigabit Ethernet, it costs you Y. A lot of these venues now offer 10-gigabit Ethernet; it'll go directly into your 10-gigabit Arista Switch ($13,000), which is just a cut-through switch that can route that packet in nanoseconds into your server, which has a kernel bypass mechanism right into memory, and you're looking at it within a handful of microseconds."
http://uk.pcmag.com/internet-products/12815/feature/inside-wall-streets-high-frequency-trading-technology-arms-r
What is the purpose of this experiment running from orbit, or from some greater distance than it had been done before? Was there some speculation that entanglement would no longer manifest due to distance or difference in velocity or within the vacuum of space or something?
Better known as 318230.
I personally like to educate myself with a box of crayons. Check mate atheists.
The Chinese people are on the slope to dominate orbital, and therefore international realtime communications.
Westerners on Slashdot spend their time bitching about the accuracy of a title of a paper.
This is how you lose.
My God, it's Full of Source!
OUTSIDE_IP=$(dig +short my.ip @outsideip.net)
Are you assuming an isotropic inertial frame of reference? If you could use Bell's theorem to communicate, you could use 2 different inertial frames of reference to receive data before you sent it.
when they can teleport electrons, protons, and neutrons. Preferably a 200 pound mass of them that happens to be in the shape of a man. Until then, yawn.
Slow down, cowboy! It has been 4 hours since you last posted. You must wait another few hours.
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
^This.
The key unexamined aspect of Star Trek is that _EVERYBODY_ already knows all this, and they just doesn't care. They've been brainwashed by Starfleet to step into to the suicide booth without a second thought. Which gives you a pretty damning characterization of the pro-transporter lobby.
the preceding comment is my own and in no way reflects the opinion of the Joint Chiefs of Staff
The comment in totality "Fuck off." is "4, insightful"?
WTF?
to the point that we can teleport all politicians up there ... and then quickly destroy the machine before they figure out what we did and try to get back again.
The problem is, elementary "particles" aren't particles in any meaningful way - the term just lingers in the vocabulary for lack of something better. For decades now it's been clear that QFT is right, and everything is a wave. There's no "duality", really, just waves that have some properties somewhat like what we might naively guess particles would have, if there were any particles. Heck, this whole "quantum teleportation" effect relies on the fact that "particle" isn't really correct.
Socialism: a lie told by totalitarians and believed by fools.
All bets are off!
Not at all, he's just being objective...
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.
You've got some derp on your chin. No, other side.
Because this is NOT teleportation. EVERY FUCKING TIME THEY DO THIS SAME SHIT AND CALL IT TELEPORTATION.
It's fucking NOT teleportation! And we're fucking sick of seeing the pop-sci HORSESHIT!
Somebody upvote here. If I'm not mistaken, I just learned something very cool! Thank you.
It's a copy of data.
Also, a scifi short story.
Uh, I see photons all the time. I would have trouble seeing without photons.
Photons are quantum objects, but not physical objects. This is because the latter consists of matter and therefor has mass.
"Tangible object" is less rigidly defined, and one could probably make a case either way for photons being tangible.
“Common sense is not so common.” — Voltaire
Witness BitZtream getting pwned!
How's life in the hypocrite lane?
It's insightful and you know it. ;)
I do not want your cheap brainburning drugs. They are useless for work. And I am a working man today.
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
Absolutely right.
And furthermore, a photon was not even what was "teleported". What was "teleported" was the polarization state of the photon. That is even less an "object".
http://www.geoffreylandis.com
A photon has no mass, because it travels at the speed of light. Nevertheless, due to energy-mass equivalence, it can exert gravitational effects.
A photon has no rest mass. It has gravitational mass: m = E/c^2
Physicists mostly use the term "mass" as shorthand to mean "rest mass". Mostly. But the word "mass" can have several possible meanings in physics, so if you want to be clear, you should specify which mass.
http://www.geoffreylandis.com
that was obviously a typo by the AC: he meant photons, not protons.
Again: the word "mass" can have several meanings in physics. When physicists are talking with each other, it is almost always clear from context which definition of mass is being used. But if there is any ambiguity in which use of the term is being intended, you must specify which. A photon has zero rest mass. (Because it can never be at rest. When you stop a photon, it ceases to exist as a photon.)
http://www.geoffreylandis.com
Tachyons, if they existed, have a rest mass that is an imaginary number.
(A difficulty with tachyons is that the theory only works in one dimension. With three spatial dimensions, tachyons become ill defined, because you can't be faster than light in all directions at the same time.)
http://www.geoffreylandis.com
Can a photon have any distinguishing characteristics that make it unique from other photons? A racing stripe, a mustache, maybe a hooked end, etc?
They are distinguished by energy and polarization.
Other than that, all photons are rigorously identical-- they are bosons, which means that they are indistinguishable (and the indistinguishability has consequences: Bose-Einstein statistics.)
How does one know it was the same photon "teleported" or just a different stray one?
What was teleported was actually the polarization state. The word "the same photon" technically has no meaning, since there's no way, even in principle, to tell whether it's "the same" or not, other than asking looking at whether it has the same quantum state (like polarization).
http://www.geoffreylandis.com