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Old October 6th 06, 02:50 AM posted to sci.space.policy
Alan Anderson
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Default Scientists teleport two different objects

(Wayne Throop) wrote:

: Alan Anderson
: It's called "teleporting" because it involves moving the quantum state
: of an object from one place to another. There is classical
: transmission of information involved, but the result of the entire
: process is indistinguishable from sci-fi teleportation.

And so is beaming a description of an object and rebuilding it.


There are two different responses to that, depending on how you want to
think of things.

1) Not so. You can't rebuild the complete quantum state of a particle,
because of Heisenberg's uncertainty principle. What you end up with is
*not* completely identical to what you started with. Information has
unavoidably been lost.

2) Yes, but only if you use the results of destroying the original
object's state by having it interact with one half of an entangled pair
to direct the manipulation of the other half. You can't rebuild it from
a description alone; you have to have the entangled pair in order for
the description to mean anything. You can't use the same description
twice in order to make another copy because you used up the second half
of the pair the first time.

Or actually moving the object, but very fast.


No, that requires that the object physically traverse the distance
between source and destination. It is not teleportation as sci-fi does
it.

Or any number of
other things that aren't teleportation, but are "indistinguisable".


What makes it teleportation is that the new object is identical in *all*
respects to the original -- which no longer exists.

Basically, since a particle has to move between source and destination,
you haven't done anything in terms of moving a macroscopic
object that you couldn't do with a cathode ray tube.


The entangled particles can have been placed at the source and
destination in advance. Then you don't need to move anything except
information in order to teleport a given object. Your cathode ray tube
sends the actual electrons from the gun to the screen.

But nobody calls
that "telportation of electrons". The fact that lots of people *do*
call *this* teleportation, and Star Trek gets mentioned prominently
in all media coverage of it, is mainly interesting because of its
relevance to human psychology and linguistics.


This is called teleportation because the word describes it accurately.