Quantum teleportation across 10 miles

This is a discussion on Quantum teleportation across 10 miles within the General Discussions forums, part of the Community Boards category; Well with all the tech news here in GD today I thought I would post this: Quantum Teleportation Achieved Across ...

  1. #1
    Super Moderator VirtualAce's Avatar
    Join Date
    Aug 2001
    Posts
    9,596

    Quantum teleportation across 10 miles

    Well with all the tech news here in GD today I thought I would post this:

    Quantum Teleportation Achieved Across 10 Miles

    This is far more interesting to me than reprogramming a few cells.

  2. #2
    spurious conceit MK27's Avatar
    Join Date
    Jul 2008
    Location
    segmentation fault
    Posts
    8,300
    I read that as meaning that the teleportation is instantaneous (ie, not at the speed of light) like gravity is instantaneous (if the sun disappeared, we would be immediately released from orbit, but not see the disappearance for eight minutes).

    Anyone know if I got that right?
    C programming resources:
    GNU C Function and Macro Index -- glibc reference manual
    The C Book -- nice online learner guide
    Current ISO draft standard
    CCAN -- new CPAN like open source library repository
    3 (different) GNU debugger tutorials: #1 -- #2 -- #3
    cpwiki -- our wiki on sourceforge

  3. #3
    (?<!re)tired Mario F.'s Avatar
    Join Date
    May 2006
    Location
    Portugal
    Posts
    7,438
    Quote Originally Posted by MK27 View Post
    Anyone know if I got that right?
    Hmm... this is not your usual self today MK. Seriously, everything alright?

    Nothing can travel faster than the speed of light. That includes information.
    The programmer’s wife tells him: “Run to the store and pick up a loaf of bread. If they have eggs, get a dozen.”
    The programmer comes home with 12 loaves of bread.


    Originally Posted by brewbuck:
    Reimplementing a large system in another language to get a 25% performance boost is nonsense. It would be cheaper to just get a computer which is 25% faster.

  4. #4
    Super Moderator VirtualAce's Avatar
    Join Date
    Aug 2001
    Posts
    9,596
    He's prob too busy playing pac-man while trying to post.

  5. #5
    (?<!re)tired Mario F.'s Avatar
    Join Date
    May 2006
    Location
    Portugal
    Posts
    7,438
    Hope he chokes on that damn thing
    The programmer’s wife tells him: “Run to the store and pick up a loaf of bread. If they have eggs, get a dozen.”
    The programmer comes home with 12 loaves of bread.


    Originally Posted by brewbuck:
    Reimplementing a large system in another language to get a 25% performance boost is nonsense. It would be cheaper to just get a computer which is 25% faster.

  6. #6
    Making mistakes
    Join Date
    Dec 2008
    Posts
    476
    Nothing can travel faster than the speed of light. That includes information.
    But somehow the phenomenon of entanglement is excluded from this, if we can describe it as "information". That also means that the earth would be released at the same time as we see the sun disappear, since gravitons are supposed to travel at the speed of light.

    We have to ask ourselves if teleportation is the instant movement of objects or the movement of their properties. From a physical POV, both are yet equivalent since there is no way to distinguish two particles with the same properties. But I don't believe this applies to conscious beings (not sure about that, anyone discovered it exactly?)

  7. #7
    spurious conceit MK27's Avatar
    Join Date
    Jul 2008
    Location
    segmentation fault
    Posts
    8,300
    Quote Originally Posted by Mario F. View Post
    Hmm... this is not your usual self today MK. Seriously, everything alright?

    Nothing can travel faster than the speed of light. That includes information.
    No, but the "entangled particles" bit implies a pre-existing relationship, as with a gravitational "field". As I said -- the effect of gravity is not bound by the speed of light.* Otherwise this would be silly, they are just transmitting.

    * does that count as information?
    C programming resources:
    GNU C Function and Macro Index -- glibc reference manual
    The C Book -- nice online learner guide
    Current ISO draft standard
    CCAN -- new CPAN like open source library repository
    3 (different) GNU debugger tutorials: #1 -- #2 -- #3
    cpwiki -- our wiki on sourceforge

  8. #8
    (?<!re)tired Mario F.'s Avatar
    Join Date
    May 2006
    Location
    Portugal
    Posts
    7,438
    If we start excluding things from special relativity on a whim, we might as well exclude special relativity.

    Entanglement does not get excluded. It simply is an extension to quantum state. Check the wikipedia article. In this case, essentially you can't describe one photon without observing both. But these are photons we are talking about. So... you know the drill by now. i.e. Speed of Light.
    The programmer’s wife tells him: “Run to the store and pick up a loaf of bread. If they have eggs, get a dozen.”
    The programmer comes home with 12 loaves of bread.


    Originally Posted by brewbuck:
    Reimplementing a large system in another language to get a 25% performance boost is nonsense. It would be cheaper to just get a computer which is 25% faster.

  9. #9
    Making mistakes
    Join Date
    Dec 2008
    Posts
    476
    as with a gravitational "field"
    If gravitation is in fact transmitted by special particles (gravitons), this is wrong. Gravitation may seem instant, but it probably isn't. It's just that it's so weak nobody noticed when the gravitational field of a faraway object disappeared, so that can't be easily measured.

    I think Heisenbergs Uncertainty Principle should be extended to cover quantum physics itself... why can't the world be just a bit more simple. And still work as we know it.

  10. #10
    spurious conceit MK27's Avatar
    Join Date
    Jul 2008
    Location
    segmentation fault
    Posts
    8,300
    Quote Originally Posted by Mario F. View Post
    If we start excluding things from special relativity on a whim, we might as well exclude special relativity.
    I understand your little mantra, but you are conceptualizing incorrectly. Again, gravity. The reason the effect of gravity is "instantaneous" is that it is already here. But again, if a sufficient mass were to disappear (which is not possible according to the laws of physics, so your information is still bound), it would not be here. Instantly.

    In this case, essentially you can't describe one photon without observing both. But these are photons we are talking about. So... you know the drill by now. i.e. Speed of Light.
    Hmm, but the change takes place at the same time -- it does not travel from one photon to the other.

    Quote Originally Posted by Brafil View Post
    If gravitation is in fact transmitted by special particles (gravitons), this is wrong.
    Okay, I had not heard of this one. So gravity remains a mystery and this is an untestable hypothesis (the instantaneousness), what about the entangled particles? Is information transmitted via some connection, or not? I think that possibility is the only thing I find intriguing here...
    Last edited by MK27; 05-21-2010 at 01:11 PM.
    C programming resources:
    GNU C Function and Macro Index -- glibc reference manual
    The C Book -- nice online learner guide
    Current ISO draft standard
    CCAN -- new CPAN like open source library repository
    3 (different) GNU debugger tutorials: #1 -- #2 -- #3
    cpwiki -- our wiki on sourceforge

  11. #11
    (?<!re)tired Mario F.'s Avatar
    Join Date
    May 2006
    Location
    Portugal
    Posts
    7,438
    Quote Originally Posted by MK27 View Post
    I understand your little mantra, but you are conceptualizing incorrectly. Again, gravity. The reason the effect of gravity is "instantaneous" is that it is already here.
    We know very little about gravity. It's unfair for you to quote what is essentially still very early work.

    Hmm, but the change takes place at the same time -- it does not travel from one photon to the other.
    At which speed do you expect your photon to travel? I suggest you read the source article: Quantum teleportation achieved over ten miles of free space. These photons are traveling.
    The programmer’s wife tells him: “Run to the store and pick up a loaf of bread. If they have eggs, get a dozen.”
    The programmer comes home with 12 loaves of bread.


    Originally Posted by brewbuck:
    Reimplementing a large system in another language to get a 25% performance boost is nonsense. It would be cheaper to just get a computer which is 25% faster.

  12. #12
    spurious conceit MK27's Avatar
    Join Date
    Jul 2008
    Location
    segmentation fault
    Posts
    8,300
    Quote Originally Posted by Brafil View Post
    If gravitation is in fact transmitted by special particles (gravitons), this is wrong. Gravitation may seem instant, but it probably isn't. It's just that it's so weak nobody noticed when the gravitational field of a faraway object disappeared, so that can't be easily measured.
    Does this mean there is the equivalent of red/blue shift in observing galactic motion (ie, they are revolving around a center that is now very far away)? I imagine that is hard to ascertain due to the influence of dark matter. Also I guess we would be observing them in the past.
    C programming resources:
    GNU C Function and Macro Index -- glibc reference manual
    The C Book -- nice online learner guide
    Current ISO draft standard
    CCAN -- new CPAN like open source library repository
    3 (different) GNU debugger tutorials: #1 -- #2 -- #3
    cpwiki -- our wiki on sourceforge

  13. #13
    spurious conceit MK27's Avatar
    Join Date
    Jul 2008
    Location
    segmentation fault
    Posts
    8,300
    Quote Originally Posted by Mario F. View Post
    At which speed do you expect your photon to travel? I suggest you read the source article: Quantum teleportation achieved over ten miles of free space. These photons are traveling.
    Yes, but the "teleportation" is not synonymous with the travelling:

    In this particular experiment, researchers maximally entangled two photons using both spatial and polarization modes and sent the one with higher energy through a ten-mile-long free space channel. They found that the distant photon was still able to respond to changes in state of the photon they held onto even at this unprecedented distance.
    This still implies to me that the "response" of the second particle is not delayed, since they refer to no means of transmission ("communicating information without needing a traditional signal") etc. Kind of irritating the writer wouldn't consider that worth clarifying.

    Since they were discussing doing this from the earth to the moon, if that were the case it would be observable. You could make a request from the moon via normal means, at a 1 second delay, and if the response then triggered on Earth involved a reply using entangled particles, you would not have to wait another second for that reply. You would receive it at the same time as your request was received on Earth (or with whatever microsecond delay was required to trigger on reception of the request).

    Of course, if this were the case, probably a bigger deal would be being made because you're right Mario, normally information is presented as bound by the speed of light. There's some details missing here, or I guess we'll be hearing that it can in the future.
    C programming resources:
    GNU C Function and Macro Index -- glibc reference manual
    The C Book -- nice online learner guide
    Current ISO draft standard
    CCAN -- new CPAN like open source library repository
    3 (different) GNU debugger tutorials: #1 -- #2 -- #3
    cpwiki -- our wiki on sourceforge

  14. #14
    (?<!re)tired Mario F.'s Avatar
    Join Date
    May 2006
    Location
    Portugal
    Posts
    7,438
    Ugh. Sorry I linked you to the wrong article. Check the link on that article "As we explained before".

    Here's a meaningful quote:
    This particular experiment involved using a magnetic field and a laser to put a trillion cesium atoms into a particular quantum state. These atoms are then entangled with a light pulse. Thus, the receiver is using a group of atoms as an entangled particle while the sender is using photons as the entangled particle. The object to be teleported is the quantum state of a second light beam. The measurement consists of combining the two beams at a partially reflective mirror and measuring their combined intensity with a light detector. The result of this measurement is then used to drive a radio frequency magnetic field to manipulate the quantum state of the cesium atoms. This replicates the polarization state of the second light field onto the spin state of the cesium atoms. At this point teleportation has occurred.
    It's not clear how this second experiment was performed. But it should have been similar to that. Note particularly the "entanglement" method. This is no quantum entanglement.
    The limitations both in transmitting or receiving information are very real to us. We may have achieved some sort of teleportation, but I can't see how we could ever do that with a technology we still don't have; That which would allows us to transfer information instantaneously. Neither this method suggests we did.

    In short... teleportation of information? Apparently yes. But still limited to the speed of the "materials" in our current technology.
    The programmer’s wife tells him: “Run to the store and pick up a loaf of bread. If they have eggs, get a dozen.”
    The programmer comes home with 12 loaves of bread.


    Originally Posted by brewbuck:
    Reimplementing a large system in another language to get a 25% performance boost is nonsense. It would be cheaper to just get a computer which is 25% faster.

  15. #15
    spurious conceit MK27's Avatar
    Join Date
    Jul 2008
    Location
    segmentation fault
    Posts
    8,300
    Yeah, in fact they need to set up communication just to accomplish the teleportation:

    First you must create a pair of particles that are in an entangled state. These particles are then shared between the receiver and the sender. The sender takes the object to be teleported and the entangled particle and performs a joint measurement on them. The sender then tells the receiver the result of that measurement, who uses that information to perform a local operation on the entangled particle. These operations cause the object's quantum state to be transfered from the object to the receiver's entangled particle. Hence teleportation is achieved.
    So it would be pointless as means of communicating information. And, as was initially explained, the "teleported" thing is not the original, it's a copy, so in that sense there is no distance involved (and no speed limit to exceed).
    C programming resources:
    GNU C Function and Macro Index -- glibc reference manual
    The C Book -- nice online learner guide
    Current ISO draft standard
    CCAN -- new CPAN like open source library repository
    3 (different) GNU debugger tutorials: #1 -- #2 -- #3
    cpwiki -- our wiki on sourceforge

Page 1 of 3 123 LastLast
Popular pages Recent additions subscribe to a feed

Similar Threads

  1. GradeInfo
    By kirksson in forum C Programming
    Replies: 23
    Last Post: 07-16-2008, 03:27 PM
  2. Unusual Counter Behavior After 10 Digits?
    By parx86 in forum C Programming
    Replies: 2
    Last Post: 07-08-2008, 01:11 PM
  3. miles per gallon program
    By JamesCole in forum C Programming
    Replies: 4
    Last Post: 10-02-2002, 10:11 AM
  4. Heaps...
    By Nutshell in forum C Programming
    Replies: 14
    Last Post: 04-23-2002, 08:54 AM
  5. Formatting Output
    By Unregistered in forum C Programming
    Replies: 6
    Last Post: 03-26-2002, 12:33 AM

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21