This blog has now come Full Circle (as M Palin would put it) as I am now at a similar position as I was when I started this thing. I now work at CERN again. My permanent post is at Incheon University, but I am the (silent) manager of a project at CERN called the SSA.
The SSA has nothing to do with what CERN is about however.
CERN has been operational since the 1960's, the World's biggest scientific collaboration. It is perhaps the largest telescope in the world. We use bigger and bigger telescopes to see into space, which by virtue of being far away, details are small. Similarly, CERN represents a telescope devoted to "seeing" the very small, by virtue of them actually being small. We call the largest one the Large Hadron Collider, the LHC.
It bashes bits together and has already been under scrutiny in this blog (Three jets are better than two). It makes Hadrons.
A "Hadron" ( pronounced " Hey! - dron!") is a particle bigger than a proton or neutron. It is important to remember that everything we see around us is made up of only protons, neutrons and electrons. "Hadrons" are created by smashing protons together to get "angry" bits - bits that don't belong in the real world. We called them "strange particles" at first, because we didn't know what they were.
Now we know that all the evidence fits like a jigsaw puzzle into thinking that all hadrons (protons, neutrons, plus angry bits) are made up of three new particles called "quarks" (from the book "Finnegan's Wake"). These quarks build up all the particles, except the electrons which seem to act like they have nothing inside at all.
All these particles are very small and behave unlike normal particles, ie billiard balls. It was first realised they were different by Neils Bohr. This was then made into a formula by Prince Louis De Broglie, and then finally made rigorous by Schrodinger et al. as Quantum Mechanics.
The basic concepts behind quantum mechanics are thus: 1. All particles also behave like waves of something ( they give answers that can only be explained by considering them as a stream of waves. "Waves of what?" I hear you say - the answer to that only comes when you understand the math behind statistics and wave mechanics - trust me) 2. You cannot know with infinite accuracy all things at the same time. 3. A new thing called 'spin" has to be called for to explain some of the things we have seen (It is NOT real "spin" as in going round and round, but just another number (we ran out of names to call these things early on)) 4. Some of the effects we have seen can be explained by a particle description AND a wave description , depending on the way we look at it. 5. These things only happen when the particles in question are very small.
So what does CERN do? Simple, we bash the bits together to get new ones, well, we used to. We have just about gotten sick of all the new bits we get out of our collisions, and now we refine the bashing to get the bits back in more useful ways. It's a bit like a car crash, we now know what bits to expect out of the car crash, but now, we bash them together at different "angles" to see which parts survive best at those angles.
The upshot of which is that we are continuing to refine the theory (Quantum ChromoDynamics or QCD) so as to predict next which bit of the engine will come out of our crash and which way it will go.
If it comes out the right way, we predict stuff about the wing mirrors, etc, if not, and we get more angry bits, we go back and try again with a different version of the theory to explain what happened before the prediction went wrong.
As for the SSA, it is just a tool to make the data collection easier, nothing fancy.
The final upshot is that there are no more angry bits any more.
1 comment:
Yes, CERN has been around a long time, but I tend to think of them as more like microscopists, rather than telescopists, although as time passed from my youth into early adulthood, I concluded that one day the various "atom smashers" of the world might have to turn to the heavens to do their studies, as the cheapest and perhaps only laboratory available to the human race.
That they have not had to do so by now is a testament to the many many scientists who work in this field and their ingenius imagination. Back with a question or two later.
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