X-Message-Number: 1102
Date: Tue, 4 Aug 92 12:24 PST
From:  (Keith Lofstrom)
Subject: Re: cryonics: #1092 - #1096

Perry, let's back off from "quoted authority" and put our speculation caps
back on.  We can get in an argument about who knows the writings of Eric
Drexler best - I've only read Engines twice and talked with Eric a dozen
times, while you probably know him from his MIT days.  

My background is different than Eric's;  I see different problems needing 
solution, some that he dismisses with a wave of a hand as engineering detail.
Well, cell repair will someday be "an engineering detail".  I like to
speculate on engineering details.  I'm an engineer, that's my job...

>     Drexler et al have
>pretty much shown that thermal jiggling on the atomic scale (not the
>electron scale) isn't an issue.

Where is this shown?  I have seen a few of Eric's studies, as regards thermal
effects on rod logic and assembler machines.  Could you direct me to a paper
on sensors, or long distance, high bandwidth communication?  In the macroscopic
world, these are two areas where cooling is used to improve performance.  Is
it inconcievable that the nanotechnological equivalents would stoop to using
these macrotechnological techniques?

Page 15, EOC, (1986 Doubleday first edition) has a paragraph on thermal
effects on assemblers.  Chapters 7 and 8 of EOC discuss room temperature
cell repair.  Chapter 9, "A Door into the Future", has a section called
"Reversing Biostasis", page 136 to 138.  This section describes repairing
a biostasis patient at LN2 temperature.  Nothing much changes between the
77K Eric assumes and the <4K I am assuming except the amount of thermal
noise, and the choice of working fluid, if any.  Wet chemistry is stopped.

This section includes such sentences as:

   "Small devices examine molecules and report their structures and positions
    to a larger computer within the cell."

There is NO natural analog to this process.  Certainly a molecule can be 
identified with an enzyme surface in a "blind" fashion - just as a book
could be "read" by comparing each page to all possible permutations of a
page, then computing which comparisons made the best "fit".  That is a heck
of a slow way to work. In an old patient there will be quite an accumulation
of damaged - but still functional - proteins that can't just be blindly
discarded.  These molecular structures will have to be examined and
modeled ad hoc, to determine which healthy structure should replace them.
Some of these molecules will have internal structure not directly accessable
to enzymatic pattern matching at the surface.  Those internal structures 
may express themselves only at room temperature.  Do we heat the patient up
with internally flawed molecules?  If so, once a cell is up to room
temperature, how do we tell which molecule is the one causing problems, 
short of boxing them up and observing them one at a time?  Too hard.  I'll
take precision measurement instead.

>Sorry. Your cells work fine operating by touch. 

Mine don't.  The damn things fail after only 3 billion seconds or so. They
don't compile any of the popular programming languages.  They eat any old
crap I put in my bloodstream, and sometimes choke on it.  They won't run
revision 2.0 DNA.  The diagnostic readout is broken.  They cost too much.
Pretty shoddy - I'm getting mine fixed at the earliest opportunity  ;-)

Seriously, we are moving from a paradigm of random transport, enzyme matching,
and wet chemistry, to a one of directed repair, central control, and 
observation and modeling in a rigid framework.  THE SAME PROCESSES DO NOT
APPLY.  When nature wants something, it builds a new one, and discards the
old one - at the cellular level or the whole organism.  The new one follows
the same blueprint as the old one, but is not a duplicate.  Cryonics attempts
to make an "improved duplicate" of the patient.  This is new ground;  I
posit a model based on machine repair rather than biological growth, though
biological processes and techniques will be among the major tools.  The 
other tools needed - IN ADDITION TO the biological ones - will be the ones
benefiting from lower temperatures.

>Your cells operate just fine without having to do such things. This is
>rapidly becoming tedious. Why don't you just read EoC and be done with
>the topic?

I guess I didn't get the special edition with the engineering details.  EOC
is a WONDERFUL book, a great start, and a real stimulus to the imagination.
It is NOT an engineering document.  It will be jokers like me that fill in
the details.  As illustrated above, we seem to have paid attention to
different parts of the book.  

>Why should we believe your claim that we have to go colder in the
>absense of any evidence at all?

Why, Perry, you can believe anything you want.  I am putting forth the idea 
that certain measurements become easier the colder you get.  Perhaps they
are easy enough at 77K, and therefore do not justify the approximately
1 megajoule needed to cool a 70Kg patient to 4K, or 3 megajoules to 0.001K
(at Carnot efficiency).  I would think that a 20x or a 70,000x improvement
in measurement accuracy, with a corresponding 8000x to a 3e14x improvement
in 3D position modeling, would justify a nickle or a dime's worth of energy.
But then, I live in a world where customers will spend $1000 for two more
bits on an analog-to-digital converter, if it is fast enough.  I'm a junkie
for accurate measurement, I guess.  It could well be that we measure every
thing cold, then do the synthesis "hot".  That would save energy.

What I am having trouble understanding is where all the hostility is coming
from.  Perry, you and I are part of a small band of brothers facing a sea of
superstitious, antagonistic moral midgets who will try to smash either of us
if given the chance.  I may someday help with your suspension or revival, as
you may help with mine.  We need each other.  Perhaps I am misinterpreting
an "East Coast - West Coast" language difference here; if so, let's get it
worked out.  Let's save our energies for battling the "Monash Menace" :-),
and BUILDING this stuff, and not fritter it away on doctrinal minutiae.

Keith Lofstrom                Voice (503)-520-1993
KLIC --- Keith Lofstrom Integrated Circuits --- "Your Ideas in Silicon"
Design Contracting in Bipolar and CMOS - Analog, Digital, and Power ICs

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