# eli5 difference between quarks and gluons

263 views

eli5 difference between quarks and gluons

In: 4

Quarks are elementary particles that make up the hadrons–mesons and baryons.

Gluons are the elementary particles that are exchanged to mediate the strong force which quarks are subject to. This is similar to how an exchange of photons mediates the electromagnetic force.

Gluons are force particles, like photons. Bosons. (although they have properties that make them behave differently from photons). They meditate the strong force.

They glue the quarks together. The quarks are the elementary particles that make up the larger particles we see: protons, neutrons, mesons and others of their family. Note, that family doesn’t include electrons or neutrinos, those are different.

Let’s say we’re playing a weird video game where a bunch of people were floating around in space, and they were all holding cannons with unlimited ammo.

When a player shoots their cannon, the force of the blast that shoots out the cannon ball will knock them back.

When a player gets hit by a cannon ball, they get knocked back by the force of the impact. The cannon ball simply disappears on impact.

In this analogy, quarks would be like the players and gluons would be like the cannon balls. Quarks are sort of the “main stuff” that makes up basically all of the universe you know (alongside electrons), while gluons are the little cannonballs that they fire at each other that knock themselves and their neighbors around.

It’s obviously a lot more complicated than that, but for a super simplified ELI5 answer, I think that highlights what I’d consider to be the biggest practical difference.

To extend the analogy just a bit, particles can actually multi-wield several “cannons”. Each one shoots a different kind of ammo, and that ammo can only hit other players that have the matching cannon. The one we were talking about, the one that shoots gluons, we could call the “strong cannon”. Only quarks have this cannon, and thus only other quarks can be hit by it. All other particles ignore shots from this cannon; they just phase straight through harmlessly.

Another cannon is the “electromagnetic cannon”. It fires cannon balls called “photons”. Maybe you’ve heard of them. Quarks have this cannon, and so do electrons, and they can hit each other with their shots.

There’s actually a third cannon, the “weak cannon”, that shoots so-called “W-bosons” and “Z-bosons”. Explaining who can use this cannon and what the cannon balls actually do is… outside the ELI5 scope. It’s a rabbit hole that’s probably quite a bit deeper than you’re bargaining for.

It’s an open question at the moment whether there’s actually a fourth cannon, the “gravity” cannon, that shoots “gravitons”. We aren’t quite sure. If it actually exists, we’re pretty sure that every particle we’ve found so far has one. Even some of the other cannon balls have one, if you can wrap your head around that. (Gluons also have their own strong cannons and can shoot other gluons, by the way… thought I’d leave that detail out until this point so things wouldn’t get too derailed.)

If you haven’t connected the dots by this point, the cannons align with the four fundamental forces.