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WTF is a particle collider?

WTF is a particle collider?
From TechCrunch - July 5, 2017

How do things work? To find out, we observe them and we take them apart. But not everything is easily observed, and until recently some things couldnt be taken apart.

Its the culmination of a theory that has its genesis in ancient Greece. The philosopher Democritus posited that if you divide a piece of matter enough times, at some point youre left with something that can no longer be dividedthis theoretical form he called atomos, or indivisible. The word of course went on to designate the atom, which we now know is not indivisible, but thats an issue of terminology; the concept is sound.

But Democritus couldnt have known (though he may have suspected) that the atomos might prove to be far more complicated than just the thinnest slice of matter possible, and that no knife would be sharp enough to make that cut. But if you explained carefully, he would certainly understand what a particle accelerator like the Large Hadron Collider does. It is the latest and most powerful, but by no means the final, tool we have built to disassemble the world around us.

A matter of scalethe scale of matter

Imagine you have a toy car. You can inquire into its physics on several levels.

If you want to know how the car rolls or how it fits together, its sufficient to watch it in action and maybe pull it apart to look at the pieces.

If you want to know why it weighs what it weighs, or why one material bends and another is rigid, you have to look closercloser, in fact, than your eyes are capable of. Thats why we invented microscopes and tests for things like how something is made up chemically.

If you want to know why those materials act the way they do, you must look closer still at the building blocks of those materialsatoms and molecules. To do this you need things like scanning electron microscopes and detailed observations of charge.

But while we can split molecules into their constituent atoms, and shave electrons and protons off of those, we soon reach the limit of what our ultra-precise electric tweezers and carefully configured radiation knives can accomplish.

And yet in all our delving we had not reached the true atomos, the indivisible. How could we go deeper? Smaller? The solution we arrived at is as brutal as it is elegant.

Little Big Bang

Particle accelerators were thought up quite a long time agogoing on a century nowand are in some ways remarkably simple.

Introduce particles like protons into a tube in which is kept a vacuum, and guide them along its length by means of magnets, all the while pushing them faster and faster. When they get going fast enough, put something in their way and BANG.

Look closely at the point of impact, and you see the traces of particles very small indeed. Protons and other subatomic particles, exposed momentarily to forces and temperatures on the order of the Big Bangs, explode into a menagerie of exotic components: positrons, antiprotons, muons, taus, charm and strange quarks and, of course, bosons. The building blocks of the building blocks of the building blocks of well, you get the idea.

Ring around the proton

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