X-Message-Number: 11322 From: Thomas Donaldson <> Subject: Some replies Date: Fri, 26 Feb 1999 23:06:41 +1100 (EST) Hi everyone! To John de Rivaz: I would actually include the case of reactors launched from Earth. As you say, this can be done so that the fuel remains subcritical until brought together in orbit. Moreover as we gain skill in launching payloads, the risk becomes less. Even now when a radioactive payload is launched it is first put into a thick lead container such that it will not burn up in the atmosphere, even if the launch fails. There are plenty of protections we can put on such a cargo --- even more than we do now. (I am not speaking about Russian launches: they seem to have less fear of nuclear material, and do not take simple precautions that Americans or Europeans would take). To Mike Perry: Basically, you believe it will someday become possible to exactly duplicate anyone or any creature that has died in the past. I do not. I doubt that these beliefs can be argued on on their merits unless we're both VERY patient. When you blithely assume that it will someday be possible to make an EXACT reconstruction of a past person or creature, you are making an assumption with which I disagree. Sure, we could (using what we know about Lucy) reconstruct a creature which resembled her in all those parameters we know, but that is hardly an exact reconstruction. Given what we know, there are many possible reconstructions of Lucy, and we'll not have any means to choosing the one which might be Lucy --- or even working out that the millions of versions we've made still does not contain Lucy. And we are NOT quantum DEVICES. Just like all matter, we obey the laws of quantum mechanics (assuming that quantum mechanics is approximately correct; as you know, we still haven't unified QM and General Relativity, a fact which casts doubt on them both). But that does not make us into DEVICES, nor for that matter does it mean that the laws of quantum mechanics play a major (or even minor) role in how we work. A DEVICE is not just something which obeys some set of laws: are we then also gravitational devices, thermodynamic devices, etc? A DEVICE is designed specifically to use some set of laws to achieve a goal of its designer. (I assume that you are not referring to any God here?). An electrical DEVICE uses the laws of electricity; a gravitational device uses laws of gravity. But everything we currently know about the working of our brain tells me that quantum mechanics plays very little direct role in how we think. Sure, our brain uses lots of chemistry, and chemistry depends on the activity of electrons belonging to the atoms involved, and electrons (given their mass) show quantum effects in cases in which no other common form of matter does. But at the level of chemistry occurring in our brain, that quantum mechanics is restricted solely to explaining how the chemistry works --- as it works in other nonorganic cases, in the entire world. That is what I mean by saying that it plays very little direct role. As for the Bekenstein bounds, please explain them or give a reference. I am not familiar with them. I do know about differential equations and the effects of nonlinearity, and given that predictions of quantum mechanics reduce to complicated partial differential equations, I in turn think that your ideas seem unlikely. Best and long long life to all, Thomas Donaldson Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=11322