Where did the term "color" property of quarks come from?

Question

I think Oscar Greenberg came up with it but was is the story behind chosing that term?

I know what it means and why the primary colors were chosen. For some reason I thought there was some funny story associated with that but I can't remember the details.

Answer 1

It came from the fact that there are only three states of 'charge' that quarks possess. Greenberg likened this to the three primary colours and he called the three states Red, Green and Blue.

Don't know why i got given a thumbs down!

Answer 2

Quark / anti-quark pairs make up mesons. An triplets of quarks make up baryons (neutrons, protons, ...). Mesons, neutrons and protons have no "color", only the quarks. You can think of the mesons and baryons as being white, or without color. In the mesons, the particle /anti-particle pairing cancels the color out leaving them white. In the baryons, the 3 primary colors (red, green, blue) combine to become white.

This is only a descriptive model. We are not actually talking about true color here.

Note that quarks do have an electrical charge, but that should note be confused with their color. And they do come in 6 flavors. Once again, flavor should not be confused with color.

Answer 3

Roughly speaking, this is the idea:

For the electric force, there are two opposites charges, positive and negative.

For the strong force, there are three opposite charges. The easiest thing at hand that has three opposites is the three primary colors. So they make a good analogy.

I'm fudging a little bit, because there are actually six types of charge, red/antired, blue/antiblue and green/antigreen.

So you can be color neutral by either like a proton or neutron with red, green and blue. Or like an antiproton or antineutron with antired, antigreen and antiblue.

Or like a pion (one of the quark/antiquark pairs) with red and antired (which shifts to blue/antiblue and green/antigreen).

Answer 4

I've always heard that quarks come in 6 different "flavors".... UP, DOWN, BOTTOM, TOP, CHARMED and STRANGE. I remember reading that the word quark was borrowed from "Finnegan's Wake" by James Joyce, but I don't know the story to which you refer, sorry.