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Man-Made Black Holes Looming?
camusflage writes: "The New York Times has a story that some physicists think it might be possible to make black holes at the under construction Large Hadron Collider at CERN, slated to come online in 2006. Trying to allay concerns about a man-made black hole blipping us out of existence, they say "The same calculations ... predict that around 100 such black holes a year are `organically' and apparently safely produced in the earth's atmosphere in cosmic ray collisions." As long as we can keep critters from building nests in the singularity, we should be okay."
We all know Black holes suck..
From the article: We've been trying for a century, and we still don't fully understand black holes," said Dr. Andrew Strominger. And then he goes on to conclude that we need to make some.
If they're going to do something which at least sounds dangerous, I would really like it if they could say, "Nothing can possibly go wrong", not, "Our understanding is incomplete."
As everyone knows, gravity is the weakest of all the fundamental forces by a very very long way, something like 40 orders of magnitude weaker than the weakest of the nuclear forces. I remember reading an article here long ago (can't find it and put a link to it because Slashdot search is down...grr) that talked about some speculation that gravity is so weak because the universe has more dimensions than the four that we see (this is also a prediction of superstring theory), and while the other three forces are only capable of propagating there, gravity is able to propagate through these extra dimensions, making it seem weaker. These dimensions are supposed to be curled up small so we don't normally notice them, so one of the implications of this theory is that the value of the universal gravitational "constant" should shoot up dramatically when you try to measure it at smaller scales; the smallest scale at which gravity has been measured so far is on the order of centimeters only. Another implication is that it should be possible to create low mass black holes with less energy than the weakness of gravity as we know it predicts. So if these scientists are successful in making such small black holes, it could go a long way to validating this theory.
Qu'on me donne six lignes écrites de la main du plus honnête homme, j'y trouverai de quoi le faire pendre.
Everybody already knows black holes spontaneously appear. Here's an experiment to prove it.
Place two matching socks in a washer machine. turn the washer machine on, wait for it to finish. Remove the single sock. Voila. Black holes.
Now place that single sock into the drier. Turn it on, wait for it to finish. Remove one entirely different sock, which you have never owned. Kazow. Alternate Dimensions.
The field of pairingsocks physics solved the Black Hole question years before the cosmologists or those silly particle physicists. This article is old news.
The simple fact is that nature still does better at creating high energy particles than anything we can do in the lab. The reason a 100 blackholes might be created in the atomsphere is because cosmic rays are still more powerful than accelerators. In fact rare extremely powerful cosmic rays, believed to be extra-galatic in origin, are still several orders of magnitude beyond what we can make.
Since these high energy cosmic rays will have the same types of collisions as they want to produce in the lab, you would expect them to produce black holes if that is possible. Any such black holes that might be produced obviously haven't destroyed the Earth thus far, so these energies are probably safe to use in a lab. Of course this may just mean that they never actually create black holes.
Regarding your other issue, nuetrinos. The reason they didn't come out right is because Super Kamiokande and the other 1st generation experiments could only detect electron and muon nuetrinos. The next generation results, which came out in the last two years, show that when you account for the number of tao nuetrinos, the total flux from the sun turns out to be right where it should be according to the theories for what goes on in stellar fusion.
The surprise here is that nuetrinos of one type can apparently turn into another type. We knew from theory how many electron nuetrinos to expect but they were hidden by changing into the other two varieties. Thus the appearance of low nuetrino counts. Flavor mixing, as it's called, is exactly what is predicted and required if nuetrinos have a non-zero mass. So we simple have to accept that nuetrinos have small but non-zero mass and figure out how this revises the "Standard Model" of particle physics.
No, we are not talking about black holes capable of swallowing matter, nor are we talking about the ability to "place them" at any particular point. Though, it does make for an interesting bit of science-fiction.
You must understand that every individual type of particles and radiants have their own, what may be referred to as, gravimetric frequency. You may note in the article that Dr. Giddings' calculations suggest that the interactions of cosmic rays and sub-atomic particles produce, what he calls, "organic," black holes, referring to naturally occurring black holes.
This team is producing the black holes from specific, fully separated subatomic particles, those being gluons and quarks. Black holes produced by collapsing stars result from still-integrated subatomic particles (matter), which remain connected gravimetrically to other large sources of gravity (fuel), are not anything to worry about here; in fact, they couldn't even be produced on the surface of the planet (the core, however, is a different idea altogether). The "man-made" varieties will only be able to effect other nearby gluons and quarks. In an vacuum-sealed accelerator, they will not be able to "find" that source of energy and will evaporate relatively quickly; though, I disagree that the result will be an abundance in the spawning of similar sub-atomic particles.
I recommend The Elegant Universe, by Brian Greene. You'll learn about how the universe works according to ideas as old as "General Relativity" to as recent as the "M-Theory".
"Yeah...it was the numbers that were irrational, not the murderous cult of vegetarians...." -- Hippasus of Metapontum
The ultimate Darwin Award
Don't worry about posting a pun. When the story is about black holes, there's no escaping it.
They better not try to put their pet black hole in a bag of holding.
Black holes have a reputation for being mass-gobbling irreversible singularities, and they are. But this doesn't mean a black hole where the Sun is would swallow the Earth. I'm not an expert so someone can correct me if they know it better or more accurately.
Any amount of mass can be turned into a black hole - you just have to crush it into a small enough space. This is because every bit of matter has an event horizon, including the Sun (or the Earth for that matter). The difference with the Sun and most things is that the event horizon for the amount of matter in the sun is smaller than the Sun. If you crushed all of Sun's matter into a sufficiently tiny space that it was all inside, then everything else that moved inside would collapse and not return.
What most people don't realise is that if the Sun spontaneously turned into a black hole, we wouldn't die from being sucked in. We'd die from lack of solar energy. Because the Sun-black-hole would have the same mass, everything orbiting it would continue to orbit it the same way it is at the moment. The only big difference would be when something happened to wander inside the event horizon at which point it wouldn't leave, if you ignore all the wierd relativity things that go on at that point at least.
So I guess the point is that just because someone says they might be able to make a black hole, it doesn't mean you'll be instantly sucked in tommorrow without any warning.
Fast forward a few years, scientists make a black hole. Why doesnt it destroy the earth?
1) The black hole weighs no more than the particles slammed together to make it. It has essentially zero pull on anything. A grain of salt would make an incredibly more effective attractor.
So you say, yes, but the black hole will persist and continue to grow in mass by swallowing more and more particles.
But the scientists in the Times article say the black hole will "evaporate".
The following paragraph, from this page, states it well:
Since the 1970s, it has been known that black holes are not completely black. In fact, they emit very low-energy radiation called Hawking radiation. The lower the mass of a black hole, the higher the energy of the emitted Hawking radiation. As a black hole radiates, its mass decreases, and it starts emitting more and more radiation, causing it to evaporate more and more rapidly. Eventually, it shrinks to around the Planck mass, the point at which its DeBroglie wavelength is equal to the Schwarzschild radius. At this point, we no longer know what happens, since to describe physics at the Planck scale requires a theory of quantum gravity.
To ensure our safety, all nuclear research should be banned until we know enough about it to know what the risks are.
From the article: We've been trying for a century, and we still don't fully understand black holes," said Dr. Andrew Strominger. And then he goes on to conclude that we need to make some.
If they're going to do something which at least sounds dangerous, I would really like it if they could say, "Nothing can possibly go wrong", not, "Our understanding is incomplete."
Actually, there's a pretty ironclad argument for this being safe - the same one that comes up every time the press starts fearmongering about more powerful accelerators:
Cosmic rays with energies far higher than will be produced by any accelerator any time soon have been striking the earth and the moon for billions of years. If high-energy collisioins could cause catastrophy, they would have already, because they've been happening in our neighbourhood for quite a while.
The fact that nothing around here has been sucked into a black hole yet leads us to conclude that if micro-black-holes can be formed, they don't do much.
Our current models of black holes suggest that micro-holes would evapourate in a burst of Hawking radiation almost as soon as they're formed. The smaller the hole, the more intense the Hawking radiation (and so the faster it loses mass).