It’s 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 you’re left with something that can no longer be divided — this 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 that’s an issue of terminology; the concept is sound.
But Democritus couldn’t 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 scale — the 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, it’s 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 closer — closer, in fact, than your eyes are capable of. That’s 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 materials — atoms 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 ago — going on a century now — and are in some ways remarkably simple offshore company.
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.
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