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Faster than Light Information Sending Solved?

  1. Feb 21, 2012 #1
    I may have figured out a way to do that, unless there is some fundamental principle I am not currently aware of. I should preface this by saying that I am not an expert. I have only recently decided to major in physics, and have not even begun school. But I just had a eureka moment. It works by combining a quantum microphone with quantum entanglement.

    Two separate quantum microphones. The atoms in the microphone would have to be entangled. Entanglement by itself doesn't transfer enough information to be useful. However, if we applied an energy circuit, such as the one made by Aaron O’Connell for the Los Alamos National Laboratory.

    It would work one of a few ways. Either the excess energy causing the microphone to be in a superposition of two states would cause the device to be in one state while transferring the excess energy to the corresponding entangled particles. As one state is disconnected (such as being muted) the other should immediately feel the loss of energy and be noticed instantaneously and definitively.

    Alternatively, applying the microphone principle (just to clarify, I'm referring to the object that is in two places at once) to one side of the quantum particles could also cause the other particles to vibrate independently of any other sources.

    Please tell me I'm over-reacting.

    EDIT: Apologies for the incoherence, I was excited and wanted to get it out on paper before I forgot it.
    Last edited: Feb 21, 2012
  2. jcsd
  3. Feb 21, 2012 #2


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    OK, you're over-reacting. :smile:

    Welcome to PhysicsForums, anthony!

    How would you know what energy an entangled particle is supposed to have? You would need to know that to measure a gain or a loss, correct? And particles that aren't observed (i.e. are not measured in some way) don't exhibit any properties by definition.

    Supposed the particles are A and B such that their energy is A+B=12. You measure A=7 so you know B=5. But there is no sense in which you can say A gained and B lost or vice versa.
  4. Feb 21, 2012 #3
    That's the beauty of it! Because of what I have dubbed "the microphone feedback," (follow me here, please!) particle A should be "cranked up to eleven" (think spinal tap) and so should impart a noticeable difference on particle B.


    Particle A Normal = 10/10
    Particle A Feedback = 11/10

    Particle B with Particle A Normal = 6
    Particle B with Particle A Feedback = 7? Higher?
    And then the other part is to consider the extra energy is coming from seemingly nowhere, and when the feedback is removed, it should disappear instantly. Right?
  5. Feb 21, 2012 #4
    Sorry. I misunderstood. I will rethink and then come back to you.
  6. Feb 21, 2012 #5
    I can't come up with any better way to explain it. Here's a link to the article I read. I'm not sure if there's more to it or not. I don't know quantum mechanics. But I would love to hear explanations for why it wouldn't work. I rationalized that it wouldn't work if it protons weren't able to be entangled, but as far as I know they are. Quantum microphones are large enough to be seen by the naked eye. It is pretty easy to tell if an object is in more than one place, I would think.

    Last edited: Feb 21, 2012
  7. Feb 21, 2012 #6
    Then I suggest you start by learning about it. :wink:

    Seriously, though, I would advise you to be extremely skeptical about eureka-moments in a subject you're not an expert - or at least very proficient - in. If you idea is really as groundbreaking as you think, learning QM shouldn't be too much of a problem. Also, it ensures the conversation doesn't take a wrong turn because people are using different definitions, 'understand' QM differently, etc.
  8. Feb 21, 2012 #7
    I completely agree. That's why I went here and didn't call the white house.
  9. Feb 21, 2012 #8


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    As I mentioned earlier, to sense a change in the state of a particle, you would need to know what state it was in prior to the measurement. By definition: once you know this earlier value for a particle, it is no longer entangled in that basis.

    I.e. there is no "difference" to observe.
  10. Feb 22, 2012 #9
    I think the main problem Anthony is that you are thinking of the entangled particles as two separate entities when they are in fact 1. You can't send information between entangled particles because they are the same particle, there's no new information that one has that the other doesn't already know about. If I hit a ball, what energy am I transferring between two balls? I'm not, I'm not transferring energy between two of anything, I'm just hitting a single ball.
    Luckily, scientists are trying to work on loopholes and recently did an experiment where they supposedly teleported an entire photon overseas by having two entangled particles and somehow shooting a photon at one particle so that it was absorbed by one particle and appeared on the other end of the world where it appeared to be emitted from that other particle, so I imagine that would be a better way to communicate. The reason this works is because the particles occupy the same state, but you are actually not adding information you are just changing relative location of something using the correlation of the states of the particles. Both the entangled particles act as one particle, so its sort of like a miniature wormhole where you make two different parts of the fabric of space meet at one point, and thus things can be instantaneously transported that distance, even though technically the distance between those two points themselves is 0 since they are in the same spot.
  11. Feb 23, 2012 #10


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    Recently? Seems to be something I missed. Do you have a reference to the experiment?
  12. Feb 23, 2012 #11
  13. Feb 24, 2012 #12


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    Hi! Those articles seem to be from 2004. Quantum teleportation neither implies teleportation of objects, nor FTL communication. Quantum teleportation is about teleporting states of objects without any direct connection. The confusion that arises is sadly due to use of the word "teleportation". This is also hinted in the articles;

    Quote from the 2nd article:
    "Quantum teleportation may have progressed from science fiction to reality. But don't look for a Star Trek transporter anytime soon. This science has little to do with beaming people from one place to another."

    Quote from the 1st article:
    "When physicists say "teleportation", they are describing the transfer of key properties from one particle to another without a physical link."

    Also read the intro on Wikipedia: Quantum teleportation. I have no more to add than this; I know the basics, but I'm not an expert on this stuff.
  14. Feb 24, 2012 #13
    I know, but quantum teleportation can't be sending information between entangled particles themselves because they technically aren't two particles, so what else could it be? If you determine the factor of one, they dis-entangle.
    Are they somehow shooting a photon at them and that changes the properties? How would they measure that without destroying the system though? I don't see many other ways to interpret the articles.
    Last edited: Feb 24, 2012
  15. Feb 26, 2012 #14


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    Reply to questionpost: Hi! All I wanted to point out was that it's impossible that the photon got absorbed in one place and appeared in another place, as this would/could imply FTL. But never mind, it seems we agree on this :wink:.

    Quote from this summary:
    If I got it right, the two measured classical bits is sent via a classical information channel, and they are used by Bob to decode b to obtain c. It is a process like this I assume the experiment above was successful in performing. But, as I said, I know very little of quantum information processing, so I can't provide a good technical explanation :redface:. I know there are other people on this forum that knows much more about it than me, so it's better someone else explains it better. Why not start a new thread about it? I'd like to learn more about it myself... :smile:
    Last edited: Feb 26, 2012
  16. Feb 26, 2012 #15
    I didn't follow all of that but let me give you the established wisdom.

    Einstein is often misquoted as having gone to his deathbed objecting to QM because "God does not play dice." In fact, he got over that one pretty quickly, but he went to his deathbed with a more powerful objection, which still remains unanswered.

    In QM, an observation is presumed to change the wave function instantaneously across long distances. He just wanted to know what kind of amazing mechanism could achieve that.

    But he did concede that the type of change we are talking about would not mess up his causality, e.g., allow you to hire an assassin to kill your own grandfather before you were even born.

    The canonical example is that you allow a scalar meson to decay into two photons. If the meson was at rest (i.e. if we choose to observe it in its rest frame) the photons must shoot off in opposite directions to conserve linear momentum. A scalar meson has no spin but both photons have spin=1. So to conserve angular momentum, both have to spin right handedly or both have to spin left handedly.

    The real deal after this decay is that both options are possible and written down in the actual state. Both options are actually happening. It might sound esoteric if you haven't read the maths, but in fact it's perfectly natural in this notation to write down that left+left and right+right are there but left+right and right+left are ruled out.

    So we let one photon fly to Venus while the other files to Mars, then we measure the spin of the former, and a microsecond later we measure the spin of the latter. Indeed, magically, the latter always knows how to agree with the former. That's pretty damned magical and it has been experimentally confirmed.

    The reason you can't use this as a superluminal telephone is that you can't *force* the first photon to be left handed or right handed. It decides by itself. You can't use this for messaging and causality is OK. But nevertheless, it's pretty damned amazing that such a mechanism exists, and nobody has any idea how it works.

    So, is your telephone any different from this?
  17. Jul 9, 2012 #16
    Honestly, my opinion, if you want to send information somewhere you still have to send it through a medium. The notion that you can just boom some light through a hole and have it appear somewhere faraway may prove superposition of atomical states but that situation has to be transmitted a distance. It just has to.
  18. Jul 9, 2012 #17
    you cannot control the outcome of the entanglement after its broken
  19. Jul 10, 2012 #18
    Information cannot be gained through entangled systems without a classical channel of information and we can prove this using a simple thought experiment. Suppose we have two entangled particles represented by Schrodinger's Cat in a box. Alice has box A and Bob has box B and they are completely separated from one another. Suppose Alice wants to send a message to Bob. There is a 50/50 chance when Alice opens her box her cat with be either dead or alive and thus Bob's cat will have a 100% chance of being in the opposite state as Alice's. However their is a fundamental problem, how do you know who opened the box first? If Alice opens her box before Bob then Alice caused Bob's cat to collapse into the predetermined state. But if Bob opens his box to early then it is Bob that caused Alice's cat to collapse into the predetermined state. It is precisely because of the fact that without a classical channel of information it is impossible to know when Alice and Bob perform their measurements and thus causality cannot be determined through quantum entanglement.
  20. Jul 13, 2012 #19
    Benowitz, wake up! You're quote "It is precisely because of the fact that without a classical channel of information it is impossible to know when Alice and Bob perform their measurements"

    What if Alice and Bob agree well ahead of time as to when exactly one of them will make thier measurement? Then they would both know who's measurement was controlling the outcome wouldn't they.

    The real reason you can't use entangled systems with a simple measurement to produce ftl is because of Ghirardi's no-communication proof. Look it up it's even got its own page on facebook.

    However the proof only applies to simple entangled systems with a simple measurement. VERY uninspiring if you ask me. People at this posting should stop referring to FTL as "impossible because of". FTL is CURRENTLY not possible, but as many of you are aware, I'm working away on gedankenexperiments that will one day make FTL or as I like to call it Instant Communication possible.

    It's just a matter of time.
  21. Jul 13, 2012 #20


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    It doesn't matter.
    No single measurement controls the outcome. Both measurements are needed to see the QM correlation. If A happens before B, and if you claim that A controlled B, you could also claim that B controlled A, retrocausally. And that's a tough pill to swallow. Correlation does not imply causation.
    A different number of particles won't change this. For two entangled particles; 1) You can't influence the entanglement, you can only measure it. 2) After the measurement, the entanglement is broken. 1) means you can't send any information via two entangled particles (you need a classical information channel for this, i.e. no FTL), and 2) means it's a "once only" process.
    FTL is not possible according to mainstream scientific theories. And that is what matters on this forum, I believe.
    Last edited: Jul 13, 2012
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