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The Big Bang Generator That Wasn't
ajs sent us a good investigative piece from the Boston Globe. Many of you recall the article about the Long Island particle accelerator that was going to try to replicate Big Bang conditions. Over the last three months, it's moved around the media, culminating with Fred Moody's scare piece about it, although the British Sunday Times recently picked it up yet again. The Globe article does a great job dissecting the actual facts behind the experiment and pokes fun at the growth of this Chicken Little-type story.
a committee of prominent physicists has also written a report, titled "Committee Report on Speculative "Disaster Scenarios" at RHIC". you can find it at http://www.bnl.gov/bnlweb/rhicreport.html . you will find the three 'disaster' scenarios described there.
sorry, no black holes or strangelets!
patrick.
They mention "strange matter" a few times, with no explanation. I am but an engineer, and not very knowledgable about such things. But surely there is a theoretical physicist in the audience who could field this question, and enlighten the Slashdot readership. Please?
thanks,
--Lenny
The Sagan idea doesn't work with this. Even if the Earth became a black hole, there would be evidence of humans having existed. Earth would be a black hole with the same gravitational pull as it has now, just no size and an accessible event horizon.
It would be a black hole with a moon and satelites, some of them artificial.
And when physicists talk about "small but non-zero probablility" remember that there is a small but non-zero probability that a baseball-sized chunk of the Sun will appear on your desk within the next five minutes, due to quantum effects.
When these guys say "small", they mean it.
Fear my wrath, please, fear my wrath?
Homer
We apologize for the inconvenience.
- The creation of runaway black holes. It is true, if you cram enough matter into a small enough volume, you may reach the density required to form a Schwarzchild-like (or, if you put some English on the particles, and some charge, Kerr-Newman) black hole. However, the Chicken Littles who worried so intensely about this phenonmenon failed to account for something simple: Hawking radiation, that is, black holes evaporate. The larger the black hole, the slower the evaporation, in contradiction to common sense. Little-bitty holes go "poof!" in a flash of radiation and heavy particles. Anyway, the aforementioned CLs (Chicken Littles) failed to do a calculation out of, say, _Black Holes: The Membrane Paradigm_, in the section under "Evaporation of Black Holes In A Thermal Bath." It's basic differential equations, not that bad. I haven't gone through them myself, but I don't exactly sweat the announced end of the world, either.
- Strange matter. A very, very hypothetical possible byproduct (and from where they get the idea that it might be produced, I don't know) of certain collisions between selected particles would produce "strangelets," that is, baryonic matter like our nuclei, but with a non-zero strangeness (a quark property). Add hypothetical to hypothetical, strangelets can convert normal matter to strangelets and dump off energy. Again, the fear of a chain reaction. Once again, they overlooked the fact that strangelets only convert free neutrons. They can't even convert neutrons inside nuclei. Now, with a mean lifetime of approximately one thousand seconds, you just don't have a lot of free neutrons floating around. You'd have to work to create these hypothetical strangelets, hope that you'd get the conversion, and then build an entirely extra particle accelerator to funnel a beam of pure neutrons at your target. Not bloody likely.
Since most of the people doing the Chicken Little routine have doctorates, they should be ashamed. All of the data I have mentioned arises from my occasional prowls through the Web on odd topics and not much more than a light understanding of black holes. No good excuse exists for their collective oversight, and one might almost imagine that it is deliberate. "No such thing as bad publicity," goes the cliche, and I'm fairly sure that most of the remarks were made by second-raters with flagging careers who would like a little extra grant money.mister attack says:
....
The idea that we are going to destroy the world with the RHIC is absolutely ridiculous. I remember reading that a large number of physicists thought the first nuclear weapon would ignite the atmosphere, destroying all life on Earth. Didn't happen.
This is a logical fallacy known as post hoc ergo propter hoc. Just because we haven't destroyed the earth in the past doesn't mean we can't do it.
Now we have a _journalist_ - not even a Ph.D. in physics - claiming that we're going to create a black hole with the RHIC.
Ad hominem. In fact, objections have been raised within the scientific community. They have been taken seriously enough to be reviewed by the laboratory. They disagreed, of course.
This is a remote possibility, to say the least - collisions at much higher energy than this happen in our upper atmosphere daily without destroying us. But assuming for a moment that a black hole is created, what happens? The answer is simple: it will evaporate.
At last a real argument. I happen to agree with you in principle; I'm not going to lose sleep over these experiments. But I don't think that going around shouting "rubbish!" at people is the way to make your point. There are valid scientific questions to be raised here, and while the field of high-energy physics may be dominated by people who believe it's perfectly safe, the objections do not come from left field. It may not be this experiment, but I would not rule out the possibility that in the near future we could devise experiments that would be capable of creating (say) a microscopic black hole.
I'd be more worried about ballistic nukes from China.
Most people should worry about a) heart disease, b) lung cancer, and c) an auto accident, in roughly that order. Since we all know that very few people give those very real dangers any thought at all
No, I don't believe RHIC is going to kill us all. But can we indeed come up with an experimental device that could? Most certainly. And human history is filled with enough follies by people who "know what they're doing" (say, Challenger) that I don't put all my trust in the intelligentsia here. The only safeguard is an atmosphere of collegiality where objections such as the one raised against RHIC are treated seriously and given due consideration in a peer review process.
That has happened, and has completed. It's only afterwards that the media really got hold of the story, and as they always do, they report it as if it were two equally valid political positions. Don't give in to the hysteria by treating all such objections with contempt.
----
Lake Effect, a weblog
lake effect weblog
{Network engineer in Chicago--looking for work!}
In my day, we didn't have particle accelerators. We had to tickle the dragon's tail with lumps of radioactive uranium isotpes. AND WE LIKED IT!
These confounded kids today with their theory of evolution, beowulf clusters, open-source operating systems. MAMBY PAMBY! HUH! In my day, Mr. Watson told us there was a world market for four or five computers and we liked it.
Well, I don't think that the world is gonna end thanks to that darn Scooby Doo and those darn meddlin' kids.
Romanes eunt domus? People called Romanes, they go the 'ouse? It says Romans go home. No it doesn't. What's Latin fo
Personally, I almost wish a black hole would sweep down from that big bad particle accelerator and wipe out earth, just so we could stop having to read these ignorant doomsayers (Fred Moody) predict the end of the world....how's that for recursive irony?
"Get out of my way! Can't you see I'm trying to save the world!!" -Xion
The idea that we are going to destroy the world with the RHIC is absolutely ridiculous. I remember reading that a large number of physicists thought the first nuclear weapon would ignite the atmosphere, destroying all life on Earth. Didn't happen. Now we have a _journalist_ - not even a Ph.D. in physics - claiming that we're going to create a black hole with the RHIC. This is a remote possibility, to say the least - collisions at much higher energy than this happen in our upper atmosphere daily without destroying us. But assuming for a moment that a black hole is created, what happens? The answer is simple: it will evaporate. Black holes lose mass constantly (a consequence of quantum mechanics). A black hole of the size that would be created by two gold ions colliding would be gone in a matter of microseconds, if I remember my astro course correctly. What's more, the Swarzschild radius would be so tiny, and the densities in the ion beam so low, that there is only a probability on the order of 1E-35 that another ion would fall past the event horizon before said event horizon disappears. In short, we have nothing to worry about. At least not from RHIC. I'd be more worried about ballistic nukes from China.