Quantum Teleportation
Teleportation is the transfer of matter from one point to another, more or less instantaneously. Teleportation has been widely utilized in works of science fiction. In some forms, it has also appeared in physical theories.
One means of teleportation proposed in fiction (e.g., The Fly, Star Trek) is the transmission of data which is used to precisely reconstruct an object or organism at its destination. However, it would be impossible to travel from one point to another instantaneously; faster than light travel, as of today, is believed to be most likely impossible. The use of this form of teleportation as a means of transport for humans would have considerable unresolved technical issues, such as recording the human body with sufficient accuracy to allow reproduction elsewhere (i.e., because of the uncertainty principle).
There's also the philosophical issue of whether destroying a human in one place and recreating a copy elsewhere would provide a sufficient experience of continuity of existence. The reassembled human might be considered a different sentience with the same memories as the original, as could be easily proved by constructing not just one, but several copies of the original and interrogating each as to the perceived uniqueness of each.
Each copy constructed using merely descriptive data, but not matter, transmitted from the origin and new matter already at the destination point would consider itself to be the true continuation of the original and yet this could not logically be true; moreover, because each copy constructed via this data-only method would be made of new matter that already existed at the destination, there would be no way, even in principle, of distinguishing the original from the copies. Many of the relevant questions are shared with the concept of mind transfer.
Teleportation Wikipedia
Teleportation is also the act or process of moving an object or person by psychokinesis. The term originated with Charles Fort, though he allegedly used it to describe magical transport between Earth and the heavens.
Telekinesis is the movement of objects by scientifically inexplicable means, as by the exercise of an occult power.
Psychokinesis is the production of motion in physical objects by the exercise of psychic or mental powers.
Quantum Teleportation is the instantaneous transference of properties from one quantum system to another without physical contact.
Teleportation is the name given by science fiction writers to the feat of making an object or person disintegrate in one place while a perfect replica appears somewhere else.
How this is accomplished is usually not explained in detail, but the general idea seems to be that the original object is scanned in such a way as to extract all the information from it, then this information is transmitted to the receiving location and used to construct the replica, not necessarily from the actual material of the original, but perhaps from atoms of the same kinds, arranged in exactly the same pattern as the original.
A teleportation machine would be like a fax machine, except that it would work on 3-dimensional objects as well as documents, it would produce an exact copy rather than an approximate facsimile, and it would destroy the original in the process of scanning it. A few science fiction writers consider teleporters that preserve the original, and the plot gets complicated when the original and teleported versions of the same person meet; but the more common kind of teleporter destroys the original, functioning as a super transportation device, not as a perfect replicator of souls and bodies.
In 1993 an international group of six scientists, including IBM Fellow Charles H. Bennett, confirmed the intuitions of the majority of science fiction writers by showing that perfect teleportation is indeed possible in principle, but only if the original is destroyed.
Until recently, teleportation was not taken seriously by scientists, because it was thought to violate the uncertainty principle of quantum mechanics, which forbids any measuring or scanning process from extracting all the information in an atom or other object.
According to the uncertainty principle, the more accurately an object is scanned, the more it is disturbed by the scanning process, until one reaches a point where the object's original state has been completely disrupted, still without having extracted enough information to make a perfect replica.
This sounds like a solid argument against teleportation: if one cannot extract enough information from an object to make a perfect copy, it would seem that a perfect copy cannot be made. But the six scientists found a way to make an end-run around this logic, using a celebrated and paradoxical feature of quantum mechanics known as the Einstein-Podolsky-Rosen effect.
In brief, they found a way to scan out part of the information from an object A, which one wishes to teleport, while causing the remaining, unscanned, part of the information to pass, via the Einstein-Podolsky-Rosen effect, into another object C which has never been in contact with A. Later, by applying to C a treatment depending on the scanned-out information, it is possible to maneuver C into exactly the same state as A was in before it was scanned.
A itself is no longer in that state, having been thoroughly disrupted by the scanning, so what has been achieved is teleportation, not replication. >P> As this figure suggests, the unscanned part of the information is conveyed from A to C by an intermediary object B, which interacts first with C and then with A. What? Can it really be correct to say "first with C and then with A"?
Surely, in order to convey something from A to C, the delivery vehicle must visit A before C, not the other way around.
But there is a subtle, unscannable kind of information that, unlike any material cargo, and even unlike ordinary information, can indeed be delivered in such a backward fashion. This subtle kind of information, also called "Einstein-Podolsky-Rosen (EPR) correlation" or "entanglement", has been at least partly understood since the 1930s when it was discussed in a famous paper by Albert Einstein, Boris Podolsky, and Nathan Rosen.
In the 1960s John Bell showed that a pair of entangled particles, which were once in contact but later move too far apart to interact directly, can exhibit individually random behavior that is too strongly correlated to be explained by classical statistics. Experiments on photons and other particles have repeatedly confirmed these correlations, thereby providing strong evidence for the validity of quantum mechanics, which neatly explains them.
Another well-known fact about EPR correlations is that they cannot by themselves deliver a meaningful and controllable message. It was thought that their only usefulness was in proving the validity of quantum mechanics. But now it is known that, through the phenomenon of quantum teleportation, they can deliver exactly that part of the information in an object which is too delicate to be scanned out and delivered by conventional methods.
This figure compares conventional facsimile transmission with quantum teleportation. In conventional facsimile transmission the original is scanned, extracting partial information about it, but remains more or less intact after the scanning process.
The scanned information is sent to the receiving station, where it is imprinted on some raw material (eg paper) to produce an approximate copy of the original. In quantum teleportation two objects B and C are first brought into contact and then separated.
Object B is taken to the sending station, while object C is taken to the receiving station. At the sending station object B is scanned together with the original object A which one wishes to teleport, yielding some information and totally disrupting the state of A and B. The scanned information is sent to the receiving station, where it is used to select one of several treatments to be applied to object C, thereby putting C into an exact replica of the former state of A.
Encyclopedia Britannica
Teleporter sends ions on long-distance journey New Scientist - February 3, 2009
A Leap for Teleporting, Between Ions Feet Apart New York Times - February 3, 2009
Teleportation Milestone Achieved Live Science - January 23, 2009
Researchers heat up gold to surprising effect: It gets harder not softer PhysOrg - January 22, 2009
First Teleportation Between Light and Matter Scientific American - October 5, 2006
Teleportation goes long distance BBC - August 2004
ALPHABETICAL INDEX OF ALL FILES
