[extropy-chat] Communication vs transportation

[scerir]

From: "Brian Lee" 

> How long until the science fiction breakthroughs come on line? 
> Transporters, etc.

If you mean teleportation we are waiting for a "physical" 
full interpretation (and then implementation) of it.

Because, talking about the transmission of quantum information
from Alice to Bob, in general and also in the usual teleportation 
scheme, we intuitively think there must be a channel connecting 
Alice and Bob. But, in this case, a paradox arises. If - look here - 
'only' two 'classical' bits were sent from Alice to Bob, by 'classical'
means, how did the 'full' quantum information pass from Alice to Bob? 
This seems to be a violation of the conservation of information,
or something like this. There are different views about it.  

Somebody thinks there is no trasmission of quantum information 
from Alice to Bob, but the (missing) quantum information is already 
there, at Bob's home, 'because' we live in a multiverse. 

Another possible view states there is 'another' channel, 
'another' path connecting Alice and Bob, which is defined 
by the two world-lines of the distributed EPR particle pair. 
This means - following Bennett - that the 'remaining' quantum information
must have been transmitted from Alice to the EPR source 'backward in 
time' and then from the EPR source to Bob 'foward in time'. 
This interpretation is fully consistent (no paradoxes like 'you can
kill your grandfather' arise here) so long as the two 'classical' 
bits Alice wish to send (to Bob) remain unknown, while that weird
informational jamming happens.