X-Message-Number: 5368
From:  (Brian Wowk)
Newsgroups: sci.cryonics
Subject: Re: Help on Hibernation
Date: 6 Dec 95 18:24:41 GMT
Message-ID: <>
References: <4a3h1v$>

In <4a3h1v$>  (RAMole) writes:

>I'm interested in interstellar colonization.  The basic situation is that
>fusion may soon give us flight times of 40-100 years.  We can probably
>send frozen embryos and artificial wombs (I've been told those should be
>easier than hearts), but we'll need either adults or good robots to raise
>the kids.  

>But we can't send adults in a wakeful state -- they eat and breathe too
>much, and  we can't afford to send huge masses of consumables. Besides
>they would go mad or die of old age during the journey.  Either fully
>frozen "sleep" or at least hibernation is required. Can anyone point me to
>a good current summary of hibernation research? Especially metabolic and
>aging rates. 

> And, what is the limiting factor on survival time in the  "almost
>freezing" (+2C ) experiments in which dogs and a baboon have been revived?
> Is there still a metabolic rate, and if so, what?  If you can near-freeze
>and revive after hours at this temperature, why not see whether you can
>after days or months?  Or do some bacteria work slowly when cold to cause

	The limit on survival time at near freezing is about 8 hours
for dogs (record held by 21st Century Medicine, Inc.).  Cryopreservation
for years requires temeratures below -135'C, which causes damage that
is not currently reversible in large animals.  Cryonics (the cryopreservation
of terminal patients) is still practiced today in hope that this
damage will be reversible by future nanotechnology (100+ years later).

	So the answer to your question is that we are still nowhere
near having a capability for biostasis or "hibernation" for years 
that is demonstrably reversible.  The good news for you is that by
the time civilization tools up for interstellar travel (50+ years
from now), this technology will almost certainly exist, so you really
have no problem.  The bad news is that millions of people who could
have been saved by the MEDICAL application of this technology (far
more important than the space travel applications) will die.

	I'll add in conclusion that I don't think hibernation or
biostasis will EVER be used for space travel, even once it exists.
By the time we get around to star travel, aging will be completely
eliminated.  Food and other material consumables can be recycled
with molecular technology (even in very small quarters) as long as
energy is available.  Virtual environments can provide entertainment,
learning, and subjective physical freedom for millenia.  There's no 
reason why anyone would *want* to turn themselves off! 

	Quite honestly, juxtaposing concerns about aging, food
stores, and boredom along with interstellar travel is a rather odd
thing to do.  It's rather like a 19th Century speculative discussion
of modern jet travel, and someone worrying about the effect
of horse manure on airport runways.  I strongly recommend you
read Eric Drexler's book, Engines of Creation, to get a glimpse
of what the next century really holds in store.

Brian Wowk
CryoCare Foundation

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