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New Heavy Ion Collider could "destroy the earth"
Sith Lord Jesus writes "According to an article in the London Sunday Times, a new nuclear accelerator designed to recreate the Big Bang might possibly--*possibly*--cause the earth to "disappear in the twinkling of an eye." Oops. " This reminds me of the some the fears that the folks in the Manhatten Project had-almost zero chance of anything occuring, but the notion of creating a black hole on the surface of the Earth is a strangely appealing one, from a sheer comedic value POV.
No, there is not a better use of money.
First of all, far, far money is spent on finding cures for horrible diseases than on high energy physics. For twenty years, the fight against horrible diseases like AIDS has soaked up research money like you wouln't believe (I think it may have been nealy 1/2 the NIH budget at one point). Personally, I don't see that we are too much better off.
As for what is learned as a result of these high energy experiments, just in the last few years we have learned that the neutrino has mass, the standard model is insufficient, we are beginning to study asymetries such as CP violation (which will explain why the universe exists), why things have mass (or at least we will have found this in the next few years with the discovery of the Higgs bosons). We know that Einstein's theories of gravitation are incomplete. I could give you an incredible list of what these experiments have and will bring to mathematics, physics and astronomy in the future.
If however, you are not interested in any of that, surely these things are important for their technological spinoffs. High energy experiments...
brought us the world wide web. Web commerce soon will exceed the money spent on high energy physics.
is the largest application of superconducting technology anywhere. Were it not for such experiments, we would not currently have superconductor based products, like MRIs.
Particle accelerators are now often used as treatment for certain cancers and blindness. Funny to think it, but these days every major hospital in the country has a particle accelerator.
Particle accelerators and storage rings are currently used as a source for x-ray or neutron studies of materials. They are used by virtually every company that makes something, from GM to Intel.
High energy physics pushes the limits of computation, finds better algorithms, expands clustering and distributed computing technologies. The fastest computer in the world is currently used for nuclear computations.
The demands of detectors push the limits of silicon and nano technologies. Curretly they are building silicon devices many times smaller than places like Intel even have the technology to do. They pioneer the use of other materials such as synthetic diamond for semiconductor devices (which are functional at far higher temperatures than silicon).
These are just the examples that come to mind off of the top of my head.
In short, in addition to their value to science, these high energy experiments push the envelope of every technology they use. The spin offs of these experiments alone are many times greater than their cost.
Answers to pressing scientific questions. Big, big, big technological spinoffs. You would be very hard pressed to find any better use of the money or manpower. I'd say that the fight against "horrible diseases" is a bigger waste of everyone's resources, but who knows, one day it might produce results, or at least make some progress that would make it worth the time and money.
So they won't say it "can't" happen, since you can't say that about anything. If you solve the quantum mechanics of picking my nose there is a nonzero probability that I will create Dark Matter which will cause the subsequent distintigration of my nose, me, and the alpha quadrant. That is what our probibalistic universe means. There is just about a nonzero probability of anything.
Back in the 70s when the first recombinant DNA experiments were taking place, there was a public outcry, mainly a result of politicians stirring up people for political reasons. They dragged a bunch of biologists into court and asked them the probability of creating dangerous organisms, as some scientists had suggested. Of course, the biologists who were about to do the experiments had carefully researched this possibility and come to the conclusion that it was extraordinary- but of course, not nonzero. When they testified, they were repeatedly asked if such a thing could never happen. They had to answer no, of course not, there is always a probability of anything happening.
Well, the experiments were banned for several years. No one in the world had any problems with inadvertant creation of dangerous organisms, and now recombinant dna experiements are commenplace. But think of the progress that was lost!
Remember that scientists are people too, and don't want the earth to collapse any more than you do. Saying that something has a small probability is about the safest assurance you can hope for, at least from a real scientist. Articles like this that attempt to use scare-mongering to whip up readership, at the expense of science, are very dangerous for everyone.
Just to make things clear, I'm a grad student in physics, working on the BaBar experiment (at SLAC in SanFran). My analysis involves kaons, which are bound states of strange quarks and up/down quarks. And yes, physics has produced many, many kaons over the years. So I think I know what I'm talking about.
--Bob
1^2=1; (-1)^2=1; 1^2=(-1)^2; 1=-1; 1=0.
The question of exactly where all of these insanely high energy particle come from is a deep mystery. Proposed answers include: Gamma Ray Bursts, Active Galactic Nuclei, interactions involving Magnetic Monopoles or Cosmic Strings, the decays of super-massive relics from the big bang, etc. For more info on these rare events, see the Pierre Auger Observatory website at www.auger.org.
Now 2.5*10^7 TeV sounds like an incredible ammount of energy compared to the .1 TeV/nucleon of RHIC, but since the cosmic rays are hitting essentially stationary nuclei in the Earth's atmosphere as opposed to the head-on collisions of RHIC, most of the energy just goes into the kinetic energy of the collision debris rather than into producing interesting physics. The relevant figure is the center of mass energy of the cosmic ray and target nucleus system. It turns out that this is equal to sqrt(2*m*E), where m is the mass of the target and E is the mass of the cosmic ray. Supposing that the target is a Nitrogen nucleus, we get sqrt(2*.014 TeV*2.5*10^7 TeV) or roughly 10^6 TeV. The corresponding figure for RHIC 2*(200 nucleons)*(100 GeV/nucleon)=4*10^4 TeV. The cosmic ray events win, but only by a bit more than an order of magnitude. (Note that this is all very much "back of the napkin" calculation, and may not be exactly right, but it's close.)
That was fun, but what does it all mean? Well, from the RHIC documentation, I figure that RHIC will have roughly 10^15 bunch crossings in each full year of collision running. Assuming that there is less than one collision per beam crossing (it makes it much easier to figure out what's going on in each collision), RHIC will produce an order of magnitude fewer collisions, with an order of magnitude lower energy density than these cosmic rays that bombard the Earth naturally. While a more careful analysis may change some of these numbers by a bit, it seems pretty unlikely that RHIC will destroy the Earth, when all of these cosmic ray collisions obviously haven't.
now, that explains why SETI is not more successful: just a few years after that aliens learnd how to send out radio waves, their curious scientists turned their plantes into black holes.. ;-)))
I'm not a Physicist, but I'll try to play one on the net. Here's what I think is the current theory:
The vacuum is full of virtual particle-antiparticle pairs, constantly forming and annihilating, with a mass-time product less than the uncertainty principle's magic number. When a pair occurs near an event horizon, one of the particles can tunnel deep enough into it to be annihilated by its antiparticle below the horizon, allowing the partner to escape - as if the particle below the horizon had tunneled out. (If there isn't an antiparticle available, there isn't energy available to kick loose the particle that didn't penetrate the event horzon. So it falls in, too, and the virtual particle-antiparticle pair disappear back into the vacuum.)
So black holes evaporate. Bigger black holes have a bigger separation between the mass and the event horizon, and thus a lower mass density just under it. So the smaller the black hole the faster it eveporates. "Evaporate" means emit a spray of energetic subatomic particles.
If I have the constants right, a stellar-sized black hole emits the odd particle now and then, a mountain-mass black hole is a good approximation of a nuclear power plant's core, and so on. But radiation reduces their mass, so the faster they radiate, the faster they shrink, and the FASTER their radiation increases, until the event horizon suddenly disappears and the remaining particles come blasting out of the former cage at nearly lightspeed. It goes BANG big-time - because this happens when there's still a lot of stuff in there. Current high-end H-bombs would blush with envy.
A black hole with the mass of a couple heavy ions would have a very short lifetime, even as compared with other subnuclear processes. Making one that would have a lifetime in seconds would consist of creating a density of matter that would push stuff through the event horizon faster than it tunnels out. That's equivalent to making a BIG atomic fireball and squeezing it down to the size of a single nucleus.
So we might see black holes as screwier-than-usual short-lived composite particles acting as intermediate steps in sunuclear reactions. But we shouldn't see a baby black hole falling quietly out of the accellerator and eating the earth.
Of course, my understanding of the model could be wrong. B-)
Or the model could be wrong. In which case, other predictions from it (such as the hole forming in the first place) are also up for grabs.
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way