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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.
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.