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Physicists Discover How To Teleport Energy

MikeChino writes "A physicist at Tohoku University in Japan has figured out how to teleport energy from one point in the universe to another. The technique is based upon prior research that shows it's possible to teleport information from one location to another, and involves making a measurement on each [of] an entangled pair of particles. The measurement on the first particle injects quantum energy into the system, and then by carefully choosing the measurement to do so on the second particle, it is possible to extract the original energy. Heady stuff, but essentially it means that you can inject energy at one point in the universe and extract it from somewhere else without changing the energy of the system as a whole."

35 of 365 comments (clear)

  1. Consistent Histories? by slifox · · Score: 5, Interesting

    How would an experiment like this be interpreted using the consistent histories theory?

    For a classic entanglement "teleportation" scenario where a measurement on one particle could cause information to be "teleported" to the state of the other particle, I think the consistent histories interpretation of quantum mechanics says that the second particle was always in the same state until it was measured, and that no information was exchanged.

    http://en.wikipedia.org/wiki/Consistent_histories

    On another note, is there a way to test if this is correct?
    Are there direct practical applications for this, if it is correct?

    1. Re:Consistent Histories? by fusiongyro · · Score: 4, Informative

      I am not the guy to answer this, but I'm going to take a stab at it.

      The article says that the prior research worked by transmitting the information separately, at the speed of light. So the idea here is apparently that the energy itself can be transmitted instantly, but you can't actually transmit information this way. Just energy.

      Still, that rocks pretty hard.

    2. Re:Consistent Histories? by CorporateSuit · · Score: 4, Funny

      Exactly. In a few decades, instead of a power cable leading to your house, you could fit your house with a 30-ton, $7,000,000 quantum disentangler! I imagine it could also be used in place of a battery on your ipad! Never worry about low battery ever again!

      --
      I am the richest astronaut ever to win the superbowl.
    3. Re:Consistent Histories? by IICV · · Score: 5, Funny

      I am not the guy to answer this, but I'm going to take a stab at it.

      You've just described Slashdot in a nutshell.

    4. Re:Consistent Histories? by Anonymous Coward · · Score: 5, Funny

      Ladies and gentlemen, I hereby present you with the first ever time travelling message! Posted in 1993, it appeared on slashdot just now.

    5. Re:Consistent Histories? by mugurel · · Score: 5, Funny

      you can't actually transmit information this way. Just energy.

      You've just described Slashdot in a nutshell.

    6. Re:Consistent Histories? by FrangoAssado · · Score: 4, Informative

      So the idea here is apparently that the energy itself can be transmitted instantly, but you can't actually transmit information this way. Just energy.

      No, energy can't be transmitted instantly. From the abstract:

      Protocols of quantum energy teleportation (QET) (...) enable the transportation of energy from a subsystem of a many-body quantum system to a distant subsystem by local operations and classical communication through ground-state entanglement. We prove two energy-entanglement inequalities for a minimal QET model. [my emphasis]

      So, you apparently still need the classical channel in order to know what measurement to perform in the receiving end, just like in good old quantum teleportation.

    7. Re:Consistent Histories? by daeley · · Score: 4, Funny

      Ladies and gentlemen, I hereby present you with the first ever time travelling message! Posted in 1993, it appeared on slashdot just now.

      You must be old here.

      --
      I watched C-beams glitter in the dark near the Tannhauser gate.
    8. Re:Consistent Histories? by Brian+Gordon · · Score: 4, Informative

      Sorry to burst your bubble but you can't transmit information faster than light.

      Period.

    9. Re:Consistent Histories? by shutdown+-p+now · · Score: 3, Insightful

      I don't understand what the hell is going on, but it seems to me that if you can send energy someplace faster than the speed of light, that could be used to transmit "information".

      In this case, you have to "measure" the particle in a particular way to retrieve the energy, and that way depends on what happened to the particle on the other side while the energy is being "pumped in" (so you cannot know in advance). So there needs to be an existing information channel to transmit the information on exact way of measurement that needs to be performed, which obeys the usual rules.

    10. Re:Consistent Histories? by InfiniteLoopCounter · · Score: 3, Interesting

      So the idea here is apparently that the energy itself can be transmitted instantly, but you can't actually transmit information this way. Just energy.

      No, energy can't be transmitted instantly... you apparently still need the classical channel in order to know what measurement to perform in the receiving end, just like in good old quantum teleportation.

      Yes. However, that is for one measurement. To really know what speed you are limited to before you can get surplus energy out on one end (eaten on the other of course), you also need to know how many possibilities there are for measurement, and how much energy you would lose in measuring the "wrong" variable.

      For instance, you could set up, say 100 such entanglements in parallel and then measure at random whether some spin is up or down at some time of some particle or whatever would be necessary at random. Chances maybe good that you get the extra energy out on, say 2 of these 10 measurements and end up coming out on top. If this were possible, you might be able to beat the classical channel speed limit all together (albeit with somewhat diminished output) over large distances.

    11. Re:Consistent Histories? by radtea · · Score: 4, Informative

      So the idea here is apparently that the energy itself can be transmitted instantly, but you can't actually transmit information this way. Just energy.

      I'm pretty much pushing a rock up hill here, but some people enjoy pointless struggle.

      Nothing is transmitted instantaneously. Not mass, not energy, not information. Nor, contrary to the article's false claims, has anyone ever teleported an electron, photon or atom, although people who don't understand quantum mechanics and physicists who would rather mislead the public to get positive mention in the press than do actual science will claim otherwise.

      The only thing that gets "teleported" is the quantum state of an atom, electron or atom. As anyone who knows anything about quantum mechanics knows, the ontology of quantum states is a slippery beast, so talking about "teleporting" one as if it was ontologically identical to a brick or Captain Kirk is pretty questionable right off.

      Teleporting a quantum state is completely different from teleporting a particle: if you could teleport a particle then the particle quantum numbers at the transmitter and receiver would change. In the case of quantum "teleportation" they do not. And the information is carried via entanglement using a perfectly ordinary beam of particles: if you were to stick your hand into the space through which information is being "teleported" the perfectly ordinary classical carrier particles would burn a hole through it.

      In the case at hand, what is being discussed appears to be a fairly tame equivalent of quantum tunnelling, in which a spatially extended object like a string is excited into a higher energy state by an interaction at one end. There may be a small but finite chance that you can then de-excite the string from the other end pretty much instantaneously, because the excited state is a state of the whole spatially extended string, although the question of the speed at which that can occur is much debated.

      Arguments over the "velocity" of the wavefunction under the barrier in quantum tunnelling have been going on since the early 1930's--there's a nice paper in Phys Rev from 1932 or thereabouts in which the authors did a pre-electronic-computer numerical solution to Schrodinger's equation to study the issue.

      So to my mind, this is pretty ordinary, although a nice way of studying a much-debated and well-known curiosity of the quantum world, that has been marketed in a misleading and dishonest way to an ignorant press by the scientists in question, or which has been picked up the the ignorant press and distorted beyond all recognition despite the scientist's attempts at an honest and clear presentation.

      --
      Blasphemy is a human right. Blasphemophobia kills.
    12. Re:Consistent Histories? by jovetoo · · Score: 4, Informative

      No. It has to do with the impedance of the cables. Since there is a lot of empty space around the powerlines in the air, there is very little loss from the electromagnetic field that is generated around the conductors by the power flowing through it. If you bury the cables, there is a lot more electrically conductive material near the power lines creating more loss of power. In effect, the power cables would lose a lot of power heating the ground around it. At least, if I remember my classes correctly.

    13. Re:Consistent Histories? by Thinboy00 · · Score: 3, Insightful

      So "teleport" is misleading since you cannot transmit power any faster than information, and that has to travel at the speed of light at most (as far as we know (this week anyway) anyway).

      --
      $ make available
    14. Re:Consistent Histories? by Fallingcow · · Score: 3, Informative

      Slashdot (sometimes abbreviated as /.) is a technology-related news website owned by Geeknet, Inc. The site, which bills itself as, "News for Nerds. Stuff that Matters", features user-submitted and evaluated current affairs news stories about a variety of science and technology related topics. Each story on the site has an Internet forum-style comments section attached. Slashdot was founded in 1997 as a blog, Chips & Dips, by Hope College computer science student Rob Malda, also known as "Commander Taco". The name "Slashdot" is described by Malda as "a sort of obnoxious parody of a URL", chosen to confuse those who tried to pronounce the URL of the site ("h-t-t-p-colon-slash-slash-slashdot-dot-org").

      Summaries of stories and links to news articles are submitted by Slashdot's own readers, and each story becomes the topic of a threaded discussion among the site's users. Discussion is moderated by a user-based moderation system in which randomly selected moderators assign points of either -1 or +1 to each comment, based on whether the comment is perceived as either normal, offtopic, insightful, redundant, interesting, or troll (among others). The site's comment and moderation system is administered by its own content management system, Slash, which is available under the GNU General Public License.

      Slashdot's traffic is estimated at approximately 5.5 million users per month, and the site has won over twenty awards, including People's Voice Awards in 2000 for Best Community Site and Best News Site. Occasionally, a story will link to a server causing a large surge of traffic, which can overwhelm some smaller or independent sites. This phenomenon is known as the "Slashdot effect".

      Wikipedia's just described Slashdot in a nutshell.

    15. Re:Consistent Histories? by Artifakt · · Score: 5, Funny

      I think there will be demand for as many as six of them, worldwide.

      --
      Who is John Cabal?
    16. Re:Consistent Histories? by Anonymous Coward · · Score: 3, Insightful

      Sorry to burst your bubble but you can't transmit information faster than light.

      Period.

      Unless the theory of relativity turns out to be incomplete as a model of the universe. But that's almost certainly impossible as all our previous theories have proved to be perfect in every respect and this one is sure to too.

    17. Re:Consistent Histories? by eggled · · Score: 5, Informative

      Almost -- has to do with safely dissipating the electric field. In buried transmission cables, losses are minimal (they are coaxial, so there's very little radiation of any kind), but they use an engineered layer of semiconductor between the conductor & the neutral sheath to create an E-field gradient. On a very high voltage line (say, 169kV & higher) this semicon becomes impractically thick (not to mention extremely susceptible to failure). When you can achieve the same thing with 20 ft of air, which is almost free (you have to buy land), and maintenance costs drop significantly (for not having to dig), it just makes sense to do overhead lines.

    18. Re:Consistent Histories? by Failed+Physicist · · Score: 5, Insightful

      Sorry to burst your bubble but you can't transmit information faster than light.

      Period*.

      *: As long as current observations that the universe is causal are not falsified.

      Fixed that for you.

    19. Re:Consistent Histories? by shutdown+-p+now · · Score: 3, Informative

      They didn't claim FTL transmission anywhere. It's still "teleport" in a sense that you don't have any wires, beams etc over which to transmit energy. The information channel still has to exist, but the requirements to it are much lighter.

    20. Re:Consistent Histories? by Kagura · · Score: 4, Funny

      A nutshell is the outer shell of a nut. Most nutshells are inedible and are removed before eating the nut meat inside. The expression "in a nutshell" (of a story, proof, etc.) means "in essence", metaphorically alluding to the fact that the essence of the nut, i.e., its edible part, is contained inside its shell.

      You've just described in a nutshell on Slashdot.

  2. Wow. by tool462 · · Score: 5, Funny

    Best. Physics quote. Ever.

    "He gives the example of a string of entangled ions oscillating back and forth in an electric field trap, a bit like Newton's balls."

    1. Re:Wow. by frosty_tsm · · Score: 4, Funny

      Best. Physics quote. Ever.

      "He gives the example of a string of entangled ions oscillating back and forth in an electric field trap, a bit like Newton's balls."

      Which we know from his laws, will continue to swing until they encounter another object or friction.

    2. Re:Wow. by geekoid · · Score: 5, Funny

      And at which point he will stiffen. Which brings us to the less known Newton's law:

      "The angle of the dangle is proportional to the heat of the meat." - Newton

      --
      The Kruger Dunning explains most post on /. http://en.wikipedia.org/wiki/Dunning%E2%80%93Kruger_effect
  3. Wow.... by Cheerio+Boy · · Score: 3, Interesting

    If you can inject enough energy into the process this could in theory be the replacement for batteries. This is provided you could make a giant transmitter that sends to the receiving devices. (Or possibly battery replacement modules?)

    This is provided the technology isn't only "ten years away" or so. ;-)

    --

    "Bah!" - Dogbert
  4. Re:Life Imitates Video Games by ArundelCastle · · Score: 3, Funny

    If you recall? It came out last week. My copy arrived today.
    Too bad the post office couldn't entangle it into my mailbox sooner.

  5. Just a theoretical preprint, premature to plug it by Anonymous Coward · · Score: 5, Informative

    Speaking as a Physicist, it seems the title should be " A physicist has posted a preprint in which he claims that "energy can be teleported"
    (as opposed to beiing transmitted)." and someone has praised it in a blog post.

    The astract says
    "Protocols of quantum energy teleportation (QET), while retaining causality and local energy conservation, enable the transportation of energy from a subsystem of a many-body quantum system to a distant subsystem by local operations and classical communication through ground-state entanglement. We prove two energy-entanglement inequalities for a minimal QET model. These relations help us to gain a profound understanding of entanglement itself as a physical resource by relating entanglement to energy as an evident physical resource. "

    note "classical communication" (i.e. a telephone call from one place to another) to tell the recipient what to do to extract the energy is needed.

    Note that an arxiv post is an assertion by an author, prior to any refereeing. The are only minimal "fences" at arxiv.org to keep out the "Einstein was wrong, I am right" nuts.

  6. Re:Life Imitates Video Games by neokushan · · Score: 5, Funny

    Yes, according to the lore they use entangled particles as a form of long range communication. EDI (Tricia Heifer of BSG fame) goes into some detail about how it works, which isn't that different from how the article here describes it.

    Bioware deserve points for doing that kind of research into the game.

    --
    +1 IDisagreeSoHeMustBeATrollOrAnAstroturferOrAShill
  7. Not faster than light, but still teleportation by Pfhorrest · · Score: 5, Informative

    People both here and on the linked blog article seem to be thinking that this "teleportation" talk is all about sending things from one place to another faster than light. That's not the big deal; it's already well-established that that cannot be done, at least not via quantum entanglement.

    The breakthrough the article is talking about is moving energy from one place to another "instantly" by means of performing the right pair of measurements on both end; but the communication between ends about what measurements to make still happens at light speed or less.

    For example, say I have a bunch of particles here on Earth and my colleagues on Mars have another bunch of particles entangled with mine. Mars is at the moment ten light-minutes away from each. On my end, I perform a measurement on (i.e. I interact with) my particles in a way which raises their energy from X joules to Y joules; I then send a radio transmission (with said transmission using less than Y-X joules) to my colleagues on Mars giving them instructions for what measurements to make on their end, i.e. I transmit information, in normal ways, at the speed of light or less.

    Ten minutes later, my colleagues on Mars get my message, perform the measurement, and BAM, the energy of their particles jumps up to Y joules. The most efficient classical alternative for transmitting that (Y-X) joules of energy would be to beam a signal of said energy between the two points, but that requires a clear line of sight between them, or some set of relays capable of carrying that signal, each of which adds inefficiency to the transmission. An even less efficient, even more classical method would be to take whatever the energy is stored in here on Earth and physically move it to its destination, which is both much slower and much less energy-efficient.

    With this method, my colleagues could be buried deep underground in a sealed lab with no way of getting anything in or out except for a limited range of radio signals carried by equipment incapable of carrying high-power signals... and still I can "beam" them arbitrary amounts of energy straight into their lab just beaming energy into some particles in my lab and then telling them over the radio what to do in their lab to receive it.

    --
    -Forrest Cameranesi, Geek of all Trades
    "I am Sam. Sam I am. I do not like trolls, flames, or spam."
  8. Re:Powerlines? by Anonymous Coward · · Score: 3, Funny

    fedex

  9. Instatanious Digital Communication by arthurpaliden · · Score: 4, Funny

    Using time sequencing you can now transfer binary data. Energy at this time code (i) no energy at this time code (0).

    So you can now have real time control of distant space craft and rovers.

  10. There's an important subtlety here by Interoperable · · Score: 4, Informative

    From the abstract of the article:

    Protocols of quantum energy teleportation (QET), while retaining causality and local energy conservation, enable the transportation of energy from a subsystem of a many-body quantum system to a distant subsystem by local operations and classical communication through ground-state entanglement.

    There's an important line in there: while retaining [...] local energy conservation. What lies at the heart of the proposal is that the measurement devices add or remove energy from the system that they are measuring. The energy is in no way removed from one location and given to another, spatially distant, location. What happens, is that a measurement device at one location gains energy from the quantum system and, based on the outcome of that measurement, the measurement device at the second location can be configured to lose energy into the quantum system at that location.

    The thing to take away is that no energy is lost or gained at either location. Instead, the measurement devices at each location gain or lose energy to compensate changes in the energy of the system. This proposal is in no way a method to teleport energy in the intuitive sense; the total energy of the quantum system and measurement device at each end is conserved. The notion that measuring a system changes the energy of the state is very fundamental in quantum mechanics and is well understood. Honestly, there's nothing particularly new about it and the paper doesn't appear to be written to be submitted to a major journal.

    This reinforces my opinion that people need to stop submitting papers they find on arXiv, especially single-author papers.

    --
    So if this is the future...where's my jet pack?
    1. Re:There's an important subtlety here by samurphy21 · · Score: 3, Funny

      I think I'm even MORE confused after reading what you wrote.

  11. I can see it now by kimvette · · Score: 4, Funny

    I can see it now:

    AT&T and Apple partner to offer the first remotely-charged cellphone. AT&T has exclusive rights on the self-charging iPhone 6G S SC until 2022. Mandatory selection of "UNLIMITED CHARGING" is required with the two-year contract at time of purchase.

    Six months later:

    AT&T has been sending cancellation notices to iPhone 6G S SC users who are heavy power users. Heavy gamers have been a drain on the charging network, so when a user reaches 200W the user will receive a courtesy call the first time, and the second time the user exceeds 200W the user's account will be shut off. Subscribers are outraged, since they expected "UNLIMITED CHARGING" means what it says.

    AT&T did not respond to our request for comment.

    --
    The Christian Right is Neither (Christian nor right). See: Matthew 23, Matthew 25, Ezekiel 16:48-50
  12. Re:Quantum "Teleportation" isn't teleportation at by Fantastic+Lad · · Score: 3, Informative

    1.) You have 2 Rubick's Cubes.
    2.) You "entagle" them by making the faces of each Cube exactly identical to the other.
    3.) You separate them physically into different geological locations.
    4.) You "measure" Cube A by turning one of its sides.
    5.) You call a handler at Cube B using a "common channel" (phone).
    6.) Cube B is "measured" by having its identical face turned exactly replicating Step 4, per the instructions received by step 5.
    7.) Repeat steps 4 through 6 until your heart is content.
    8.) Bring the Cubes together, and marvel that their faces are still identical to each other.

    Except that isn't how it works.

    Here's a neat page which goes to some lengths to explain why people are excited and mystified by this particular feature of reality.

    It is a high school science level presentation, but frankly, that's my level and with something as peculiar as Quantum Entanglement, it helps to go through the steps as a refresher. If you want to skip ahead, then the goods can be found on this page.

    -FL