Gluon

The gluon is an elementary particle that carries the strong nuclear force.

Gluons are a very sticky business. With gluons you can stick quarks together, as if the gluon is super glue. Therefore, gluons are used in the recipes for protons, neutrons and pions.

If you don’t achieve results right away, check out the crafting rules for the quark combinations.

Gluons are the carriers of a force. We call this force the strong force. Gluons only carry the strong force between particles that have a color charge. The only particles with a color charge are the quarks. So in practice, the gluons carry the strong force from one quark to another. Like this, the quarks are aware of each other's presence. The quarks are attracted to each other because they exchange gluons.

Dive deeper into the Physics: gluons
A gluon is a messenger particle. The gluons carry the strong nuclear force between particles with a color charge. The only matter particles with a color charge are the quarks, so only quarks can ‘throw’ and ‘catch’ gluons which makes them experience the strong force.

The gluons always cause an attraction between the quarks, never a repulsion. This is in contrast to, for example, the electromagnetic force where equal charges (+ + or - -) repel each other while opposite charges (+ -) attract each other.

The gluons ensure that the quarks stay together, they glue the quarks together (as glue).

Gluons themselves also have a color charge! As a result, the gluons are also able to emit gluons. That is why the strong nuclear force between quarks is so strong. The gluons make more gluons themselves. It is like glue would make more glue. Before you know it the sticky glue is everywhere.