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Colliding Particles Can Make Black Holes After All
cremeglace writes with this excerpt from ScienceNOW:
"You've heard the controversy. Particle physicists predict the world's new highest-energy atom smasher, the Large Hadron Collider (LHC) near Geneva, Switzerland, might create tiny black holes, which they say would be a fantastic discovery. Some doomsayers fear those black holes might gobble up the Earth — physicists say that's impossible — and have petitioned the United Nations to stop the $5.5 billion LHC. Curiously, though, nobody had ever shown that the prevailing theory of gravity, Einstein's theory of general relativity, actually predicts that a black hole can be made this way. Now a computer model shows conclusively for the first time that a particle collision really can make a black hole."
That said, they estimate the required energy for creating a black hole this way to be roughly "a quintillion times higher than the LHC's maximum"; though if one of the theories requiring compact extra dimensions is true, the energy could be lower.
I don't see how you can prove something conclusively in silico, you put in what you know and you get a distillation of it out. How can you discover* completely new physics when the computer can only start with a potentially incorrect/inaccurate theory and make deterministic calculations based on that input? I mean, you can't get out more than you put in, can you?
Caveat: I can easily accept that collisions of the same energy take place all the time in nature, even if a hole were somehow formed I have far more confidence in Hawking than someone who can scream "Think of the Children!!!" while keeping a straight face.
*There's no reason why you can't put in your theory and come out with a simulation that doesn't resemble how things happen in nature and so begin to disprove a theory. That being said, if CERN could have shown the existence of the Higgs boson using only simulations then they might not have bothered with the LHC.
If God forks the Universe every time you roll a die, he'd better have a damned good memory.
Because I have several computer models that predict what I should trade to become fabulously wealthy. Excellent!
The funny thing is some people will point to this model and say, "OMG SEE EVIDENCE OF TEH BLACKHOLEZ OF DOOM!!!" While in the same sentence say, "Models of Global Warming are just MODELS, made up COMPUTER SIMULATIONZ!!!"
Gee, what's wrong with this sentence:
Now a computer model shows conclusively...
I'm sure the research modeling is interesting and worthwhile, and it's just the writeup that is idiotic. But y'know *computer* models do not ever show anything *conclusively*. The model is only as good as the assumptions that went into designing it. Those might be good and reasonable guesses, but you are only doing the model because you *haven't* (or can't) observe the actual phenomenon.
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This can be explained very simply.
Shutting down the LHC will not inconvenience these people in the least.
Telling them not to use their SUV to drive to the corner store all the time, or to use it for a one person long distance commute to work will inconvenience them.
Not true either. At the energies the LHC will collide, not the protons collide, but the constituent quarks and gluons. In fact, when producing very massive objects, it will be the quarks constituting the proton, the so-called valence quarks, that interact; gluons and the so-called sea-quarks are extremely unlikely to reach those energies. So you would end up with some fractional charge. A detail, maybe, but as an LHC physicist, I like things correct :-).
The comparison to the helium atom is wrong too: helium ions, stripped of their electrons, exert quite an electrical pull on their surroundings. But usually they very quickly recombine into neutral helium atoms. Or they have to be accelerated such that their kinetic energy is to large to form a stable atom.
Finally, the comment about the mass of the moving proton is plain wrong too. The only thing that matters to calculate the gravitational pull of the created object is it's rest mass. The relativistic mass that is being referred depends on the frame of reference (and is therefore an uninteresting quantity we never really work with). Imagine the force being dependent on the frame of reference...
That all being said, I agree the whole apocalyptic story is plain stupid, but as scientists we cannot afford using wrong arguments. And we need better PR maybe, because a 1/quintillion (or whatever probability limit set) is maybe not zero, but should be rounded down as such for public dissemination.
I am more likely to trust a peer review from the guys at the LHC, when they talk about their research, than the IPCC folks, when they talk about theirs.
Both cause me puzzlement, since how can a (necessarily imperfect and incomplete) computer model conclusively prove anything???
Either the scientists have too much faith in their own genius, or the Science Now "journalist" doesn't know how to critically think.
"I don't know, therefore Aliens" Wafflebox1