Originally posted September 10th 2008. Will still be relevant, or even more so, after the thing is actually fixed and running : )
People seem to be under the impression that simulating the conditions of the early Universe is a crowning achievement of mankind unrivaled by nature. I'll get to that in a bit, but first, I'd like to point out a pattern.
did not end the world.RHIC
did not end the world.
And after the Large Hadron Collider
performs its first experiment, we're still going to be here.
What news outlets and some crazy bloggers enjoy omitting is that we don't build particle accelerators because we have no way of otherwise peering into the phenomenon that were present during the early Universe. The LHC may be a marvel of modern technology, but both its predecessors and successors are nothing more than fancy cosmic ray
generators, and not terribly powerful ones at that.
But how frequent are cosmic rays of the sorts of power that the Large Hadron Collider is going to be producing? There is actually a formula
to estimate this.
N(>E) = k(E + 1)^-a
Where E is the value in GeV, k is about ~5,000 particles per steradian
per square meter per second, and a is about 1.6. N is the resulting rate of cosmic ray influx over the corresponding area.
For the LHC, E would be about 14,000. Assuming your body has an average face of about a quarter of a square meter or so, k becomes 5,000 * .25 * 2*pi (we will operate under the assumption that the Earth blocks all of the cosmic rays that we are interested in measuring), or about 7,850.
7,850 * (14,000 + 1)^-1.6 = ~548 seconds per, or a bit more than six cosmic rays strike your body with more intensity than the LHC will ever generate, every single hour.
It doesn't suffice to extrapolate this to just the Earth, but also every single astronomical body we have a continuous observation of. Uncountable numbers of such collisions occur on bodies that we see every single second, and yet, no object under our gaze has mysteriously turned into a black hole. And no, a celestial body becoming a black hole - even a small celestial body - would not be a subtle event. Black holes are messy eaters, to the point where they blast most of their food away.
Scientists say it won't happen simply because, in real astronomical terms, the LHC is a child's toy, and these collisions happen nearly every minute of every day on every square meter of our planet, and the Moon, and the Sun, and... It's not that the collisions can happen that interests us, it's the how, the why, the repeatability, and the extensive data we get from the results.
You need to get to energies a billion times more powerful
before you start entering territory not commonly found in modern nature. And when we get there, -then- we can talk about how we might not want to host such an experiment on Earth - neverminding that a zevatron would probably need to be bigger than Earth in the first place.
So please. There are more important things to worry about. You can go to bed safely knowing that some crazy experiment in Europe is not going to swallow the Earth, because if the LHC is a danger, your own home is far more dangerous still.
And if some uneducated cretin tries to tell you otherwise, give them the equation above and let them work out the math for themselves.
Have a nice day.