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Black Holes From the LHC Could Last For Minutes
KentuckyFC writes "There is absolutely, positively, definitely no chance of the LHC destroying the planet (or this way either) when it eventually switches on some time later this year. And yet a few niggling doubts are persuading some scientists to run through their figures again. One potential method of destruction is that the LHC will create tiny black holes that could swallow everything in their path, including the planet. Various scientists have said this will not happen because the black holes would decay before they could do any damage. But physicists who have re-run the calculations now say that the mini black holes produced by the LHC could last for seconds, possibly minutes. Of course, the real question is whether they decay faster than they can grow. The new calculations suggest that the decay mechanism should win over and that the catastrophic growth of a black hole from the LHC 'does not seem possible' (abstract). But shouldn't we require better assurance than that?"
Heh - when you're talking about a black hole at or smaller than the size of an atomic nucleus it doesn't matter whether it's at the top of the atmosphere or at the center of the Earth. Matter at that scale is described as tenuous at best. You'd have to get somewhere like the center of the sun or denser before a collision would be anywhere near likely.
The gift of death metal does not smile on the good looking.
If such stable black holes were creatable / existed, we should see rather remarkable things with old white dwarfs and neutron stars, which would be greatly affected by such energy sources.
> What happens if one of these black holes happens to intercept a spacecraft as it leaves
> or re-enters the atmosphere? Does it do significant damage?
No. Try to understand how small these holes would be. They are so tiny that in the unlikely event that they hit the nucleus of an atom they would almost certainly pass through with out interacting at all with any of the subatomic particles there. Your spacecraft is going to be hit by cosmic rays with far more energy and with a far higher probability of interacting.
Warning: this article may contain humor, sarcasm, parody, and perhaps even irony. Read at your own risk.
I think that pretty much sums up the way that the scientists on these kind of projects really think about these things, and I find it reassuring. They are just as unenthusiastic about the prospect disappearing into nothingness as you are. They are smarter than me. They are also almost certainly smarter than you. If they are comfortable enough to joke/make bets then I'm not worried.
Actually, cosmic rays, which regularly (read: constantly) enter our atmosphere, have energies up to 10^20 eV. The LHC uses 7 TeV protons and ~500 TeV lead nuclei. That's on the order of 10^12 to 10^14 eV.
So, you have it backwards. We don't produce particle at anywhere near the energy they're produced in nature.
What I find more interesting is that if these miniature black holes can give off a minute of Hawking radiation then it means the final seconds of a black hole look less like a bomb and more like a really bright flashbulb. This is great news for some science fiction authors as it means potential Hawking radiation reactors are actually NOT suicidal for a species to build.
Actually, a black hole at mars orbit wouldn't do any damage (to us) because if it swallowed up Mars, it would have the same mass as mars, thus leaving everything else untouched. A black hole on earth would well, not be enjoyable for us.
No, actually, the black hole is so very minuscule (10^-27 meters) that it could fall straight through a nucleus without absorbing anything.
For comparison, a proton is ~10^-16 meters. Or was that a quark? I'm not off by more than two or three orders of magnitude, anyway, which scarcely matters for this.