From: Hal Finney (hal@rain.org)
Date: Fri Oct 23 1998 - 12:07:46 MDT
John Clark, <jonkc@worldnet.att.net>, writes:
> I can instantly change the state of your receiver 1000 light years away
> but I can't send you a message. The message is "encoded" and until you
> get the equivalent of a one time pad it looks random to you. I can't send
> you the one time pad ahead of time because I don't know what it will be,
> I only find out when I actually send the particular message and quantum
> process create one, so now the only way I have to get the one time pad to
> you is by old fashioned radio. 1000 years from now when you receive the
> one time pad you can confirm that I have instantly changed one apparently
> random state of you receiver into another apparently random state. They
> weren't really random of course but they would look that way to you
> until you got the pad.
This notion of instantaneous transmission of "encoded" information doesn't
strike me as a very good analogy.
For one thing, the "speed" of transmission is potentially more than
instantaneous. If you insist on thinking of this as transmission of
information, the problem is that it can go into the past as well. It
can even go into the past light cone of the "transmitter", which makes
it faster than "faster than light".
Also (or equivalently), there is no well defined moment of reception.
Particularly in the case of quantum teleportation, where you are not
making measurements of the receiving system, you can't point to a time
at which the information was received. You almost want to say that the
information travelled backwards in time to the point where the reception
particle was created, then forward with that particle throughout its
lifetime until the teleportation was done.
There are enough differences from what we normally mean by the phrase
that I don't think it is useful to call this phenomenon "transmission of
information" at all.
Hal
This archive was generated by hypermail 2.1.5 : Fri Nov 01 2002 - 14:49:41 MST