X-Message-Number: 1966 From: (Thomas Donaldson) Subject: Re: cryonics: #1936-#1942 Date: Sun, 14 Mar 93 13:04:05 PST To Ralph Merkle: Cracking seems to be one of the major (but not the only) sources of damage which ANY method of repair must be able to fix. Rather than rely solely on a "mature nanotechnology", which MAY only come centuries from now (many a slip between cup and lip!) if we had some way to avoid cracking, we'd also have some way to reduce the difficulty of repair. Perhaps enough for an IMMATURE nanotechnology. Furthermore, although it seems likely, it's far from obvious that cracking in a frozen brain leaves all the pieces just where they were originally, ready to be assembled. Cracking occurs because of stresses; without closely examining frozen brains (not necessarily human ones!) we don't have any good empirical data on just what the damage is. The stresses may bear especially on surfaces we don't want to separate, like synapses; they may also cause movement of the cracked pieces... so that the puzzle ceases to be quite so easy to put together again. Of course I, and I believe those working and thinking about this problem, would agree totally with you that whatever means of storage is chosen, it should be equal or very close to simple storage in LN2 when compared in terms of likelihood of catastrophic failure, expense, and other such criteria --- including, of course, the potential longevity of storage. Best and long long life, Thomas Donaldson -- Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=1966