Re: Beaming Up via Nanotech

From: Robert J. Bradbury (bradbury@aeiveos.com)
Date: Thu Dec 28 2000 - 18:50:41 MST


Luke mentioned to me that he thought this topic would have
drawn more discussion, I replied to him offlist. My
comments to him are included here for posterity... with some
additional thoughts at the end.

================================================================
It is fine, I suspect the reason it didn't get discussed much is
that it has been discussed before. We don't have a really good
answer for the "killing copies (or the original)" ethics problem.

I believe in one of the "Physics of Star Trek" books discusses
the problem of "transporters" and concluded "can't be done".
The problem is that the type, location, bonding, etc. of every
atom in the body is a very large amount of information.
The topic came up over a lunch table at the Foresight Conf. in November.
While I was dubious about transporters, Ralph Merkle argued that
it wasn't really a problem with enough compression. I had already
concluded when reading the Star Trek analysis, that with the proper
compression (based on knowing the human genome, the polymorphisms
in an individual has, etc.) that it might be feasible. Ralph argued
that it certainly was, but I'm unconvinced yet, as the non-redundant
data in the brain alone is not small and it isn't clear how much
you can compress it without losing something important.

Then even if the "transporter" problem is solvable, you have to address
the energy loss over interstellar distances. Unless you have solar system
or larger sized receivers on the far end it is going to be a very big
waste of power (due to all those photons that miss the receiver as the
beam spreads out). I think you *really* need to sit and do some very
complete "cost-of-transmission" analysis. I've thought about doing
a paper on it, but unfortunately it isn't high on my list.

Because of the compression required, you probably only get transporters
that "must" function in biohazard filter mode (i.e. you get back the
person, but lose anything considered hazardous). Now, you will get
into an interesting situation for someone infected with say the
prion protein because if they believe "who they are" is a "prion
infected person", then they may want the biohazards transmitted
as well. Transmission of the extra information (to reanimate you
as a precise mental replicat of yourself who you *really* are) is going to cost
data in the brain alone is not small and it isn't clear how much
you can compress it without losing something important.

Then even if the "transporter" problem is solvable, you have to address
the energy loss over interstellar distances. Unless you have solar system
or larger sized receivers on the far end it is going to be a very big
waste of power (due to all those photons that miss the receiver as the
beam spreads out). I think you *really* need to sit and do some very
complete "cost-of-transmission" analysis. I've thought about doing
a paper on it, but unfortunately it isn't high on my list.

Because of the compression required, you probably only get transporters
that "must" function in biohazard filter mode (i.e. you get back the
person, but lose anything considered hazardous). Now, you will get
into an interesting situation for someone infected with say the
prion protein because if they believe "who they are" is a "prion
infected person", then they may want the biohazards transmitted
as well. Transmission of the extra information (to reanimate you
as a precise mental replica of yourself), e.g. who you *really* are
is going to cost extra!
                                                                                
I believe, that Moravec's "Harvard Doesn't Believe in Science
Fiction" piece has some useful commentary on the "conscious
selves" vs. "instantiations" perception problem. Its here:
  http://www.aeiveos.com/~bradbury/Authors/Computing/Moravec-H/HDPSF.html
I'm not sure whether the copy with shutdown followed by the reanimation
of the original with "pasted" experiential difference information
solves the ethical problem. It could be argued since you have
become a 2nd individual (on an alternate time line), that pasting
the new memories back onto first constitutes murder. You can
argue that is feasible *if* you argue that the body in stasis
is the property of your mind (even though your mind may be in
another body someplace else or circulating bits in a Matrioshka
Brain). Thus far Greg hasn't let me successfully argue that
bodies or bodies + minds are the property of other minds
because doing so opens the Pandora's box that higher level
entities can treat you as a disposable diaper. Which is
pretty much how God treats us now, so perhaps it is nothing
more than a continuation of the current reality...
=======================================================================

I believe that the energy losses due to the fact that any
transmission beam will spread out over the long interstellar
distances is one reason Robert Freitas thinks probes are the way
to transmit information. Now, if Spike would just finish
his interstellar dust ablation calculations we would know
how much matter gets lost due to "rampaging" space dust.
Then we might be able to finally solve the radio/optical SETI
vs. probe debate. Using E = mc^2, we could figure out whether
the lost photons or the eroded shields is really more valuable!
Since faster probes are going to cost more due to the
expense of accelerating them to higher velocities
(and they are going to erode faster, meaning you need
a larger shield), I suspect you can come up with a very
exact equation saying when you transport by photons and
when you transport by matter. Then you have to apply
a discount function to that because the photon transmitted
information is always going to arrive earler.

Robert



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