Want to read Slashdot from your mobile device? Point it at m.slashdot.org and keep reading!

 


Forgot your password?
Close
typodupeerror
×
Network Privacy Security Space Transportation News Science Technology

German Scientists Successfully Teleport Classical Information (upi.com) 107

Posted by BeauHD from the beam-me-up-Scotty dept.
An anonymous reader writes from an article on UPI: Using a series of laser beams, a pair of German scientists teleported information without the transfer or matter of energy. "Elementary particles such as electrons and light particles exist per se in a spatially delocalized state," Alexander Szameit, a professor at the University of Jena, explained in a press release. Classical information is coupled using a process called "entanglement." "As can be done with the physical states of elementary particles, the properties of light beams can also be entangled," said research Marco Ornigotti. "You link the information you would like to transmit to a particular property of the light." Researchers used polarization to encode information within a laser beam, enabling the teleportation of information instantly and in its entirety without loss of time. Whereas quantum information and quantum systems describe particle properties that are inferred, classical information describes physical properties directly measured.
This discussion has been archived. No new comments can be posted.

German Scientists Successfully Teleport Classical Information More

German Scientists Successfully Teleport Classical Information

Comments Filter:

  • Let me get this straight (Score:4, Interesting)

    by wierd_w ( 1375923 ) on Sunday March 13, 2016 @05:14AM (#51688569)

    They just figured out non-local data transmission at FTL speeds.

    They arent transmitting quantum states, they are transmitting polarization data, which can be used to encode classical information, and transmitted such classical information.

    This means that you can transmit from point A to point B, "instantly", as long as you can entangle the two points.

    Does this mean that causality is only a suggestion, or will the physical constraint of having to usefully entangle the two points save the day here?

    • If they have figured out data transmission at FTL speeds (which is hard to tell just from the summary and without the right Ph.D.) then yes, that suggests a violation of causality, or at least a need to redefine it.

      However, it is much more likely (based on... the observed universe up to now...) that either something about the system predetermines the output at both locations, or that the output at one point is known to be distinct or the same as the other but that there is no way to influence what the outco

      • Re: (Score:1)

        by Anonymous Coward

        they probably hid the causality

        Unless you're being metaphorical, no, a major point of quantum mechanics is precisely that there aren't hidden variables. Honestly, it doesn't surprise me at all that causality isn't universally linked. The whole notion of an information code limiting the speed of information to light speed and any violation of this being a sign of travel backwards in time always seemed rather absurd to me. If time is relative, then it would seem to reason that causality would have to be at

        • "hid" in the sense of "some information transfer is happening in a way they don't realize" or "they are not actually transmitting information," not in the sense of "information transfer by a hidden variable determining something that appears to be but is not a probability distribution"

        • Re: (Score:2)

          by bytesex ( 112972 )

          So, if I may see if I understand your post well enough:
          - there is causality
          - there is the speed of light
          - but they're not necessarily connected, that is to say:
          - if the sun explodes, we experience most of the effects 8 minutes later (speed of light and causality in one), but:
          - if you transfer information between two points instantly using quantum entanglement, you experience causality, but not the speed of light.

          • you experience causality, but not the speed of light.

            That's a contradiction in terminis. The speed of light is a misnomer. The c denoting the speed of light actually stands for causality. c is the speed of causality. There can, however, be a difference in the simultaneity for different observers, making it appear that events appear to happen in moments that are different for others, making it appear as if causality has been broken.

        • Relativity (Score:4, Informative)

          by Roger W Moore ( 538166 ) on Sunday March 13, 2016 @11:24AM (#51689461) Journal

          If time is relative, then it would seem to reason that causality would have to be at best local to one's own time frame.

          Only it doesn't work like that at all in relativity: causality is preserved by the fact that information cannot travel faster than light. If you can transmit information faster than this then you can create real paradoxes which are not at all explainable i.e. events which occur in one reference frame and which do not occur in another because someone stopped them. This is not something which has ever been observed.

          My guess is that the information speed is actually less than, or equal, to that of light because we have seen this sort of thing before with tunnelling photons. A photon can tunnel through a potential barrier faster than light but the chance that it makes it is less than 100%. This means that you have to send many photons to be sure the signal is transmitted and by the time you do that the average speed of information transmission has dropped to the speed of light even though single photons are faster.

          I don't know the details of this experiment yet but I very, very strongly doubt that they actually transmit "actionable" information (i.e. information that could influence an observer's actions) at FTL speeds and I expect that the summary misread and misunderstood the results.

          • They transmitted information "instantaneously" between different properties but at the same location. Nothing traveled faster than light. The part about "across multiple locations" is fiction unrelated to this experiment. They even admit that "With this form of teleportation, we can, however, not bridge any given distance".

          • Re: (Score:2)

            by mysidia ( 191772 )

            Ii.e. events which occur in one reference frame and which do not occur in another because someone stopped them.

            Perhaps, you could say that Faster than Light Transmission is instant, because it "Skips" space.

            Then the space of potential valid reference frames you can construct becomes discontinuous.

            In other words, those "Reference frames that are paradoxes" , are actually invalid reference frames which do not even exist, for transmission of information that "skips" over spacetime directly from send

            • Perhaps, you could say that Faster than Light Transmission is instant, because it "Skips" space.

              It doesn't matter how the information is transmitted all that matters is that there is a causal link between two events which requires any form of FTL information transmission. Provided that event A causes event B then for ANY type of FTL transmission there will be a reference frame for which event A occurs after event B and hence it is possible to stop event A from happening after seeing event B which was caused by it. The only way around this is to break relativity or break causality.

        • Causality really is independent of the observer.

          If two events cannot be causally related in the reference frame of some observer (time difference t, and distance more than t times c), then two different observers may disagree on which of the two happened first. One may say supernova A exploded before B did, another may say that B exploded first, and yet another may say they exploded exactly simultaneously, but it doesn't matter since neither event could have affected (or caused) the other. No information co

        • Re: (Score:2)

          by HiThere ( 15173 )

          Yes, but ....
          My guess is that time is two different things that we call by the same name, thus creating confusion. ONE of the things started with the big bang. The other pre-existed it, and was necessary for the big bang to have time to happen (in). The one that started with the big bang is probably entropy. The other is ??? sequencing? Is it even measurable? I can't wrap my head around it, but some sort of pre-existingness has to exist for the big bang to have a time and place to happen. And to assu

    • Re: (Score:1)

      by Anonymous Coward

      From TFPaper [arxiv.org]:

      [...] we have shown that teleportation is a general concept, that transcends the distinction between classical or quantum systems, and that non-locality ultimately differentiates between these two realms.

      So no, the classical form is local (not FTL).

    • Re: (Score:2)

      by gweihir ( 88907 )

      At the moment it means this does not work over large distances. At short enough distances causality begins to become fuzzy, so such a loop-hole might be credible. Alternatively, they measured something else than they think they measured and this is a faulty result. That would of course be exceptionally boring, so I hope the result is valid.

    • Re: (Score:3, Informative)

      by michelcolman ( 1208008 )

      They didn't figure out "non-local data transmission at FTL speeds".

      They figured out local transmission without loss of time, i.e. encoding information into the polarization of a light beam, instantaneously, but without bridging any distance.

      Quote: "With this form of teleportation, we can, however, not bridge any given distance," admits Szameit. "On the contrary, classic teleportation only works locally."

      The rest is just the usual hyperbole and Star Trek comparisons by people who don't know what they're talk

    • Re:Let me get this straight (Score:4, Informative)

      by SoftwareArtist ( 1472499 ) on Sunday March 13, 2016 @01:22PM (#51689875)

      No, the article was just written by a completely clueless person who had no idea what they were talking about. I looked up the original paper, and the answer is right there in the abstract:

      For many years, however, it has been implicitly assumed that this scheme is of inherently nonlocal nature, and therefore exclusive to quantum systems[...] We present an optical implementation of the teleportation protocol solely based on classical entanglement between spatial and modal degrees of freedom, entirely independent of nonlocality.

      This effect is, in their words, "entirely independent of nonlocality." The information is being transmitted through space in the ordinary way, traveling no faster than light. The person who wrote the summary just made up the part about "instantly" and "without loss of time."

      • How *dare* you bring facts into a Slashdot argument?

        Have you no pride at all?

        LOL :_)

      • Re: (Score:2)

        by bentcd ( 690786 )

        No, the article was just written by a completely clueless person who had no idea what they were talking about. I looked up the original paper, and the answer is right there in the abstract:

        I can't say I blame them. I blame whichever nitwit it was who decided "quantum teleportation" would be a good term to use for the phenomenon.

        "Quantum teleportation" is nothing like the traditional notion of teleportation at all, in any way shape or form. To call it this is to invite misunderstanding and erroneous interpretation and the name is doing science great disservice.

        My best guess is the term was invented by a scientist desperately looking for grants, in the hopes that this type of dishonest name wou

    • I'm a big scifi nerd and I'd love for FTL travel/communication to be proven possible, but if it ever is, it likely won't be via quantum entanglement.

      Here's an analogy: We have a red ball and a black ball. We randomly put each one into a sealed box so that it's impossible to tell which ball is in which. I take one on my spaceship and fly away from you at top speed, you do the same in the opposite direction. When we're a light year apart, we both open our boxes. Mine is red, so I immediately know that you

    • Does this mean that causality is only a suggestion, or will the physical constraint of having to usefully entangle the two points save the day here?

      Causation is only violated for superluminal propagation. If you don't propagate there is no violation.

    • Surely without knowing the state @ both ends first this can't work https://en.wikipedia.org/wiki/... [wikipedia.org]

  • Never any description (Score:4, Interesting)

    by evanh ( 627108 ) on Sunday March 13, 2016 @05:25AM (#51688585)

    I always check each of these type of news items, hoping one may attempt to explain how it works. Alas, no such luck yet again. :(

    • The basic gist that I can derive, is that the polarization state of one beam is directly entangled with the polarization state of the other beam.

      So, if you measure the polarization of beam A, you will instantly know the polarization state of beam B.

      This is more useful than the quantum states of individual photons A and B, which is what we had previously-- because the state of the polarization is not destroyed by the measurement, and the polarization of the beams can be manipulated to encode data.

      This means

      • Re: (Score:2)

        by frnic ( 98517 )

        I think that is true, but only after beam A reaches location B - so, if we wanted FTL communications with Alpha Centura we would have to wait 4 years before we could start sending.

        • Re:Never any description (Score:4, Interesting)

          by wierd_w ( 1375923 ) on Sunday March 13, 2016 @06:03AM (#51688659)

          That's still very useful for a number of situations.

          1) Ship en-route to Alpha Centauri-- They entangle their transmitter and receptor beams at the launch, stay in realtime contact the entire flight. Flight takes many decades, but they stay in contact with earth in realtime. (as long as the beams never lose power, and thus stop being entangled.)

          2) SETI wants to talk to aliens in a target system. They send the rough equivalent of a modem's negotiation signal for however many years it takes for polarized light to get there. Hopefully, the aliens know about this kind of entanglement, and can entangle their own beam with the incoming polarized light. The aliens can now alter the polarization state of the beam on earth, and send a return message. The return message is received "instantly." Once the channel is open, realtime communication is possible.

          Neither of those is possible with traditional entangled photons.

          • 1) Ship en-route to Alpha Centauri-- They entangle their transmitter and receptor beams at the launch, stay in realtime contact the entire flight. Flight takes many decades, but they stay in contact with earth in realtime. (as long as the beams never lose power, and thus stop being entangled.)

            My knowledge of physics is admittedly not as good as I'd like, but would this be subject to any relativistic effects? We don't have anything that can go a substantial fraction of the speed of light, but it seems i

          • The techniques could potentially be useful a lot closer to home than Alpha Centauri. Communication even with Mars is greatly complicated by the transmission delay. But can you really send signals that can affect actions taken at a distance at FTL speeds without violating causality?

          • ...but it utterly breaks causality (Score:4, Informative)

            by Roger W Moore ( 538166 ) on Sunday March 13, 2016 @11:40AM (#51689521) Journal

            Flight takes many decades, but they stay in contact with earth in realtime.

            This utterly breaks causality. For example suppose a terrorist had planted a bomb on the ship and uses this instant signal to detonate it. However nearby our hero Buzz Lightyear is cruising in the opposite direction at a large fraction of the speed of light. He sees the ship explode but in his frame of reference the terrorist of Earth has not actually pushed the button yet so he carries on flying to Earth and shoots the terrorist before the signal is sent....so why did the ship explode? ...and if it didn't explode why did Buzz fly to Earth and shoot someone?

            The moment you have FTL information transmission you have time travel: the two are inextricably linked in relativity and the moment you have time travel you have causality violations. So either this experiment does not transmit actionable information FTL or there is a serious flaw with relativity. The later would be an extraordinary claim which requires extraordinary evidence.

          • That's not how it works. First, while once the aliens measure the polarization of the beam, they know the polarization of our beam, but we don't even know that they know that (because we can't tell if they've measure their beam or not). Secondly, once the aliens would entangle their beam with another beam, it destroys the entanglement with the original beam, which means the two things are no longer correlated. Entanglement doesn't allow you to choose the state of your system, it only allows you to know, onc

        • Unfortunately, the beams don't leave the device. You'd have to mail the other end, calibrate it, and then establish the beam. You would never beat a radio to a new location; or even a rocket, since you'll need one.

    • I would have told these guys about the "Law of No Communication" but apparently they didn't get the memo

  • Work-around FTL? (Score:3)

    by l0n3s0m3phr34k ( 2613107 ) on Sunday March 13, 2016 @05:32AM (#51688599)
    I was thinking a few days ago, that perhaps the reason this might work is because the entangled pairs when moved apart are moved at non-light speeds. Therefor, even though it may NOW be transmitting at what seems FTL, the entangled system "as a whole" (including the moving apart of the entangled pair) isn't moving anything at FTL. I realize this is a total metaphysical explanation...
    • Saying entanglement is like teleportation is basically the same as saying that one-time pad is like PKI. With OTP, you distribute key material 'ahead of time' (just like you distribute parts of an entangled system) and then you can magically 'communicate' (securely in the case of OTP, instantaneously in case of teleportation). This all works only because you distributed things beforehand and then conveniently forgot that part. Even then, entanglement-based 'teleportation' is useless. If you forget fancy la

      • Re: (Score:2)

        by bytesex ( 112972 )

        So, the latency is terrible, but the throughput - wow!

      • Why reply to me? I never mentioned teleportation in my post...

  • Under 'classical information' I first thought of a piece of parchment with a statement written with a goose-feather, _that_ would have been cool!

    • Re: (Score:2)

      by rossdee ( 243626 )

      Was it one of Beethoven;s symphonies?

      Meanwhile in the USA, universities are seeking grants to fund research into teleportation of Soul and Rap

  • Boring: Not in violation of locality. (Score:5, Informative)

    by extensive ( 323657 ) on Sunday March 13, 2016 @06:20AM (#51688699) Homepage
    From the press release: "With this form of teleportation, we can, however, not bridge any given distance," admits Szameit. "On the contrary, classic teleportation only works locally." http://www.uni-jena.de/en/Rese... [uni-jena.de]

    • Re: (Score:2)

      by gweihir ( 88907 )

      That explains it. Thanks. Localized phenomena can seem to violate established laws of physics under certain circumstances and not break the whole thing.

    • So you can send information faster than light, but only if it doesn't actually go to any other place? Send information from A to A instantly? Damn, I knew I should have gotten a patent on that while I still could!

  • ...without the transfer or matter of energy.

    Come on it is the first line of the summary and a glaring error editors.

  • "Elementary particles such as electrons and light particles exist per se in a spatially delocalized state."

    A bit like Iowans, then?

  • I just watched this (https://www.youtube.com/watch?v=dEaecUuEqfc) which says such a thing should be impossible.

  • Funny how even tried to attack me when I suggested the possibility...

  • SETI (Score:3)

    by l0n3s0m3phr34k ( 2613107 ) on Sunday March 13, 2016 @12:37PM (#51689721)
    Tech like this would explain why SETI hasn't turned up anything. We've only been transmitting EM for around 150 years, and if this tech actually works in another 50 years this will probably be the main comms for all probes, off-world colonies, etc. In another 100, it would replace most other communication systems. That is, of course, assuming, President Trump or President Cruz don't start WWIII lol.

  • >>> Researchers used polarization to encode information within a laser beam, enabling the teleportation of information instantly and in its entirety without loss of time.

    Wait they transmitted information between two locations faster than the speed of light? I thought quantum physics states that even entaglement can't break the speed of light?

  • Information in on one beam, information out on two beams. That is about it right? This breaks quantum encryption on fibre optic links does it not, because you can duplicate a state without interfering with the original in a detectable manner?

    However if you were dreaming of faster pizza deliveries this is not what the work is all about.
  • This supports the theory that people who think "information" (aka a human concept created by human thought) cannot transfer faster than the speed of light have absolutely no logical basis for thinking that other than observations of the non-quantum mechanics of the universe, which obviously is a flawed basis to begin with. Then they look at black holes and stick their fingers in their ears and go "nah nah nah can't hear you" and pretend black holes aren't part of the observable, measurable, simulatable uni

Slashdot Top Deals

Our business in life is not to succeed but to continue to fail in high spirits. -- Robert Louis Stevenson

Close