Remember all that beef about the possibility of the LHC producing uncontrollable black holes that could DESTROY TEH WORLD OMG? Well, it’s still highly unlikely, but it turns out that the way these things are calculated aren’t as reassuring as we might perhaps want them to be:
The problem is compounded when the chances of a planet-destroying event are deemed to be tiny. In that case, these chances are dwarfed by the chances of an error in the argument. “If the probability estimate given by an argument is dwarfed by the chance that the argument itself is flawed, then the estimate is suspect,” say Ord and co.
Nobody at CERN has put a figure on the chances of the LHC destroying the planet. One study simply said: “there is no risk of any significance whatsoever from such black holes”.
Which means we are left with the possibility that their argument is wrong which Ord reckons conservatively to be about 10^-4, meaning that out of a sample of 10,000 independent arguments of similar apparent merit, one would have a serious error.
In layman’s terms, the above doesn’t mean that the LHC is dangerous, it just means that the assurances of its safety are predicated on flaky calculations. The difference between the two is left as an exercise for the reader. 😉 [via SlashDot; image by muriel_vd]
*sigh* Another damn radio episode of Torchwood…
Cosmic ray particles with higher energies — and we’re talking about seven *orders of magnitude* larger energies per particle — than the LHC can ever produce hit Earth’s atmosphere. See Wikipedia: http://en.wikipedia.org/wiki/Cosmic_ray . To quote:
“Cosmic rays can have energies of over 1020 eV, far higher than the 1012 to 1013 eV that man-made particle accelerators can produce.”
Such ultra-high-energy cosmic rays (http://en.wikipedia.org/wiki/Ultra-high-energy_cosmic_ray ), where a single subatomic particle like a proton has the kinetic energy of a baseball thrown at 60 miles per hour, have been detected 15 times since 1962.
Meaning that A) there are probably many more such events; and B) that this has been happening for a very long time already (think millions or billions of years).
Still, no black holes have been falling from the sky and eating the Earth, as far as I can see. The LHC is not going to produce Earth-destroying black holes, not by a long shot.
Just in case anyone was confused by Jetse’s notation, what was meant was: 10^20 eV, comparing to 10^12 to 10^13 eV. Superscripts and subscripts are always a bother when transcribing text…