Date: Mon, 30 Jun 2003 00:12:43 -0400 (EDT) From: "Keith F. Lynch" <kfl at KeithLynch.net> To: WSFA members <WSFAlist at KeithLynch.net> Subject: [WSFA] Re: fw: one more thing to worry about Reply-To: WSFA members <WSFAlist at keithlynch.net> Ron Kean wrote: > The possibility of runaway chain reactions reemerged when scientists > began deploying advanced particle accelerators, like the Cosmotron > built at Long Island's Brookhaven National Labs in 1952. Some > scientists worried that slamming protons into antiprotons at > extremely high velocities might generate an unnatural subatomic > template to which other particles would bind, collapsing matter > into a void, possibly for vast distances. Cosmic rays with energies many orders of magnitude higher than has been reached in any man-made accelerator strike our planet every day. > ... Kurt Vonnegut's 1963 novel Cat's Cradle, in which a researcher > inadvertently creates "ice-nine," a template molecule that turns > water into a solid at room temperature. There was also concern a few years later with "poly-water," i.e. water in thin capillaries which had very different physical properties than ordinary water. Could it somehow catalyze the polymerization of all of our planet's water? Fortunately, poly-water turned out not to exist. Whatever happened to Kurt Vonnegut? I don't think I've heard of anything by him in the past thirty years or so. Nor have I ever seen him at a con. > In his new book, Our Final Hour, Rees worries that power > improvements in atom smashers like Brookhaven's new Relativistic > Heavy Ion Collider might make these machines capable of creating a > black hole that would scarf up the globe. This happens in James Hogan's _Thrice Upon a Time_. Once there are hundreds of quantum black holes flying around randomly inside our planet, getting larger every hour, what can be done about it? Hogan came up with a unique solution. > Ever more powerful accelerators, he fears, might create a > "strangelet" of ultracompressed quarks - the smallest known units of > matter - that would serve as an ice-nine for the entire universe, > causing all matter to bind to the strangelet and disappear. I hate it when that happens. Does this remind anyone else of what the aliens in "Plan Nine From Outer Space" warned would happen? While the special effects in that much-maligned movie were execrable, at least by today's standards, the plot doesn't seem any sillier than that of any present-day movie. One threat that the author of this _Wired_ article missed is Bose- Einstein condensation. It was only achieved in the lab in 1995. To condense a small amount of matter requires an extremely low temperature, on the order of a few nanokelvins. This may be colder than anything has ever been before, anywhere, ever. Unfortunately, to condense a larger amount of matter doesn't require as low a temperature, if there's already a small Bose-Einstein condensate available to catalyze it, in much the same way as laser light can catalyze more laser light, without limit. If it's really large, it doesn't have to be particularly cold at all. It's not inconceivable that our whole planet could get Bose-Einstein condensed if we're not careful. > Since, fundamentally, matter seems to be made of very rapidly > spinning nothingness, there may be no reason why it couldn't > spontaneously return to nothing. Since a universe-wide catastrophe has never happened, we have no information on it. Is the planet, and the universe, fundamentally robust, or fundamentally fragile? Different people answer differently. It's as much a matter of psychology as knowledge of physics. > "The present vacuum could be fragile and unstable," Rees frets in > his book. A particle accelerator might cause a tiny bit of space > to undergo a "phase transition" back to the primordial not-anything > condition that preceded the big bang. Nothingness would expand > at the speed of light, deleting everything in its path. Owing to > light speed, not even advanced aliens would see the mega-destructo > wave front coming. In other words, a careless Brookhaven postdoc > chopsticking Chinese takeout might inadvertently destroy the cosmos. Something sort of like this happens in Greg Egan's _Schild's Ladder_. Except the phase transition expands at only half the speed of light, allowing some time to react. And it isn't nothingness on the other side, but the laws of physics are quite different there. It's not a new idea. In the 19th century, when it was thought that light travels in "luminiferous ether," it was soon realized that since transverse but not longitudinal waves travel in it, it must be a solid, and it must be under tremendous negative pressure everywhere, like the skin of a child's balloon. A rip in the ether would propagate at the speed of light, and unravel the whole universe, like a balloon popping. The 19th century also originated the "heat death of the universe," in which the cosmos just runs down like a steam engine that's out of fuel. Steve Smith <sgs at aginc.net> wrote: > Rees seems to be making a career out of doomsday scenarios. I find > it difficult to believe that we're the first in the Cosmos to > develop particle accelerators, I've seen no evidence that there are any other civilizations out there. If there were, and their development was even 1% faster, or their planet began 1% sooner, they would have expanded to consume all available resources by now. We wouldn't need sensitive SETI receivers to figure out if they exist. They would have already long since arrived here, and dismantled our planet for spare parts. Someone has to be first, and it looks like it just might be us. However, as I pointed out, natural cosmic rays are much more powerful than any accelerator we have ever built. > or that we can create conditions that don't occur naturally, even in > things like colliding black holes. In terms of energies, our largest powerful H-bombs are utterly trivial. Even an ordinary hurricane is more powerful. It is possible, however, that our H-bombs have reached temperatures larger than had ever before been reached on earth (except on a sub-microscopic scale from cosmic rays). Of course temperatures elsewhere are far higher. But what about *low* temperature? I can't think of any natural process that could reach nanokelvins, at least not in a universe this young. (It's not true that nothing in nature can get colder than the cosmic microwave background. Expanding interstellar gas clouds can. But probably not by that many orders of magnitude.) And it's plausible that we've generated stronger *coherent* radio waves than have ever occurred in nature. Not that anyone's come up with any danger from them. Other than attracting unwelcome attention from other civilization or from their automated planet-killer robots, of course. > Me? I just worry abut the fact that oxygen + nitrogen is an > unstable combination. No it isn't. I'm still kind of unclear on where all the free oxygen came from in the first place. Where is the material it used to be combined with? Surely there isn't enough coal, oil, and natural gas to consume all the oxygen in the atmosphere. And the rocks are already fully oxidized. My best guess is that it was originally in the form of water. The water vapor drifted to the upper atmosphere (the present stratospheric cold-trap must not have been in operation then) and photo-dissociated into hydrogen and oxygen, and the hydrogen was lost to space. But everyone else seems convinced that our oxygen atmosphere was the work of living things, and that a lifeless world would have no free oxygen. What am I missing? Ron Kean wrote: > That is a powerful argument for the extreme unlikelihood of a > universe destroying accident, be it artificial or natural. But it > leaves open the possibility of a planet wide catastrophe, since > numerous such events might have occurred elsewhere without us > knowing. True. So it's a good idea to have offsite backups for our civilization, i.e. self-sufficient space colonies. Too bad our present International Space Station is not a step in that direction. > At high temperatures, nitrous oxide N2O exothermically decomposes > as follows > 2N2O yields 2N2 + O2 Similarly with all other nitrogen oxides. There are a whole bunch of them. Nitrogen really wants to combine only with itself. Which is why nitrogen compounds make good explosives. Though if you want to read a nitrogen oxide disaster novel, I recommend Hal Clement's _The Nitrogen Fix_. If I recall correctly, the nitrogen oxides have to be maintained by imported alien vegetation. It doesn't just happen. Hal knows too much chemistry for that. -- Keith F. Lynch - kfl at keithlynch.net - http://keithlynch.net/ I always welcome replies to my e-mail, postings, and web pages, but unsolicited bulk e-mail (spam) is not acceptable. Please do not send me HTML, "rich text," or attachments, as all such email is discarded unread.