From: Steve Schear <schear@lvdi.net>
Date: Wed, 28 Jan 1998 11:59:14 +0800
To: Jim Choate <cypherpunks@cyberpass.net
Subject: Planetary rovers, SETI and other musings, was Re: update.356 (fwd)
In-Reply-To: <199801272132.PAA01922@einstein.ssz.com>
Message-ID: <v03102800b0f45774adc0@[208.129.55.202]>
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>ANOTHER VERSION OF QUANTUM TELEPORTATION is
>being published by researchers in Italy and England (Francesco
>DeMartini, University of Rome, demartini@axcasp.caspur.it).  Like
>the Innsbruck teleportation scheme published several weeks earlier
>(Update 351), this demonstration employs a pair of entangled
>photons.   Whereas the Innsbruck experiment teleported the
>polarization value of a third, distinct "message photon" to one of
>the entangled photons, the Rome scheme encodes one of the
>entangled photons with a specific polarization state and transmits
>this state to the other entangled photon. Although different from the
>Innsbruck experiment (which had a 25% teleportation success rate)
>and the original theoretical proposal for teleportation, this scheme
>works 100% of the time if the receiver applies the right
>transformations on the second photon.

I wonder how far off use of this technique for interplanetary rovers might
be (10 years, 20 years)?  Remote (Earth) rover manipulation is tedious at
best due to several minutes (or an hour or more to the outer planets) of
propagation delay.  Autonomous rovers need enough smarts built-in to handle
unexpected situations, a non-trivial problem.  An alternative is to
establish a link using entangled photons. If a simple approach to saving
these entangled states during signal transit, in both directions, were
found instantaneous communication and simplified remote control would be a
reality.

Of course one needn't stop there.  If entangled states could be stored for
several years, instantaneous communication with neighbooring stars is a
real possibility.  Coupled with advances in mind-machine science it might
someday be possible to explore, first-hand, our local portion of the galaxy
without leaving earth, or upload/download one's consciouness to vessels in
remote locations.

Speaking of which, do the current SETI programs check for signal modulation
using polarization.  If we've discovered this trick, sure so have other
intelligent life forms.  Most natural sources of radiation tend to
unpolarized, so a rapidly flucuating polar modularion might easily appear
to be noise.

--Steve