Structure of Matter

Quarks are Confined


The strong force is radically different from gravitational and electromagnetic forces. With gravity and electromagnetism, the farther apart the objects or charges are, the weaker the force. However, with the strong force, distance does not matter. The strength of the strong force stays constant.

So what happens when a quark is kicked hard?
Why do only color neutral particles appear?


Quark Confinement

What happens if you try to separate two quarks?
If a quark is somehow pulled away from its neighbors, the field of the strong force "stretches" between the quarks.
Like a rubber band being stretched, more and more energy goes into the field as the quarks are pulled apart.
When there is enough energy in the field, the energy will be converted into a new quark/antiquark pair.
Energy is still conserved because the energy in the field was converted into the mass of the new quarks.
In addition, the field of the strong force has returned to a relaxed state.

Thus, quarks cannot exist individually.