How the Large Hadron Collider proton beam is turned off

"Please do not place hands in path of beam."

True, but due to copper's heat conducting properties I would think it would be the worst thing you could put in the beam's path (next to your hand).

It is the future of space-based weaponry.

I'm sad to have not been involved in such awesome experiments.

Oh man, you make me want to replay the Orange Box right now.

For those who don't know, Half-Life is a computer game series centered around a cataclysmic event at a secret underground high-energy physics laboratory dubbed Black Mesa.

Highly recommended :)

"I built the gluon gun, but I've never been able to use it on a living soul!"

(I may be paraphrasing. It's been years since I heard that line delivered, and it was probably 2am at the time.)

The article refers to beams of "hundreds of trillions of protons". That's very, very few in chemistry terms. Ten hundred trillion (which is the upper limit of the number which that phrase could be talking about) is 10^15. Avogadro's number is 6 x 10^23. So we're talking about 1.6 billionths of a mole of protons.

Let's assume that all turns into hydrogen -- that's as good a hypothesis as any. While randomly Googling for the value of the ideal gas constant (the R in PV=nRT; I note in passing that Google has rendered my prized copy of the CRC Handbook obsolete in a flash) I found the even handier sentence:

The molar volume of any gas at STP is known to be 22.414 L/mol

Which implies that we'll make about 4x10^(-5) milliliters of hydrogen at STP. About enough to fill a cube 330 microns on a side. And that's if we turn them into a gas, which isn't exactly dense.

The moral of this story is that statistical mechanics deals with very large numbers of particles. The second moral is that it's not the current in the proton beam that will kill you. It's the voltage, aka the energy of the protons. Which is not surprising -- if you want to simulate the Big Bang, you need a lot of bang.