The Rules of Play
SCIENCE | By Ethan Gysbertsen
Welcome back. Nice to see you again. How have you been? How’s your family? Now that we’ve got the pleasantries out of the way, it's time to continue our discussion. Remember the basics? Then let us move on to:
The Rules of Play
The Universe operates on four fundamental forces with which all the particles in the Universe interact. Keeping to the shallows of this subject, the four forces are:
The force of gravity is the attraction between stuff across space. Everything in the Universe that has energy (energy usually means mass) attracts everything else in the Universe that has energy, meaning you are being affected by the gravity from every single particle in the Universe and you are affecting every particle in the Universe the same way. Gravity is what causes things to fall towards the Earth, it is what keeps the Earth in orbit around the sun, and it is what caused the gases that formed the sun to collect in the first place. But back to the important role gravity plays in the Universe at large, it is actually the weakest of the fundamental forces. Think about it. You can counter the gravity of the entire planet just by lifting your arm. It’s really easy. Gravitational force also loses its limited strength rather quickly. Every time you move away from a source of gravity, for every unit of distance you move away, you lose twice as much attraction as the last time you moved away. This is called an inverse ratio.
2. The Electromagnetic Force
This force is much stronger than gravity and runs our entire civilization. It holds electrons around atoms, it causes magnets to attract, and it generates light particles. This force works by the attraction and repulsion of two charges: positive and negative. Positive charges attract negative charges and similar charges repel. This force is transferred between particles by photons (the previously mentioned light particles); which are particles in an invisible field that permeates the Universe, the electromagnetic field. What you know as electricity is the build up and movement of negatively charged electrons which carry charges from one place to another. Allowing these negative charges to move to places that lack electrons (and are therefore positively charged) is what makes this force power our appliances. Since electricity and magnetism are actually the same force, you can generate one from the other under certain circumstances; for example, if you wrap a copper wire around a piece of metal and run a current through it, that piece of metal will become magnetized.
3. The Strong Nuclear Force
Also known as the strong interaction, color force, and nuclear force, the strong force is the strongest of the forces (who'd have guessed) and pretty important in that it holds atoms together in two ways; it keeps the nucleus of atoms from exploding, and it keeps the things in the nucleus from exploding. The particles in the nucleus, collectively known as nucleons, are made up of three quarks each; now there's a bunch of stuff to know about quarks, but for now just know that they aren't made of anything, and the only reason they hang out together to make nucleons is that they are bound by the exchange of particles known as gluons; it is this exchange of gluons that makes up the strong nuclear force. The second way that this force keeps you from disintegrating is that the particles in the nucleus don't want to be there; one of the two types of nucleons is positively charged, so when you have a bunch together in the same place they want to get away from each other as fast as possible because same charges repel. Enter the strong force once again, but a little different. This time the gluons are actually making another force carrier particle that works between nucleons, called pions, which are a little weaker and made of two quarks. Funny thing about the strong force, when particles are super close together it actually repels them; its only when they wander slightly further that the strongest force in the Universe has something to say. But after a bit the power of the strong force drops dramatically, so it doesn't have a large range.
4. The Weak Nuclear Force
Now, I don't know about you guys, but whenever I hear about the weak force, I mostly get, "something something nuclear decay something something something something." And now I know why. It is really, really complicated stuff. I'll try to keep it simple, but feel free to skip this one. Also called the weak interaction, this force acts over just the freaking tiniest distances and it has two force carrier particles, the W and Z gauge bosons (Ws have charge, Zs don't). Now for the complex stuff. Going back to the nucleons, the quarks that make them up come in six types or 'flavors', two are needed to make nucleons. These two types are called up and down quarks. The type of nucleon is determined by one of two possible arraignments of these quarks, two up quarks and one down quark, or two down quarks and one up quark. Basically the weak force is capable of changing the flavor of quarks, and therefore changing one type of nucleon into the other. So if say a neutrino (a type of very small particle) flew very close to one of these nucleons and threw a positively charged W boson at it, the neutrino having lost some positive charge could change into a negatively charged electron, and the neutrally charged nucleon it passed by could become a positively charged nucleon, which would then completely change the type of element that nucleon was a part of. This is called particle decay and is how carbon dating works.