On Thu, 5 May 2005, Mark A. Mandel wrote: > The physicists call it "spin". They also speak of "charm" and "color". Those are names > for characteristics that don't exist in the world of our senses. These particles aren't > charming, they're smaller than visible light wavelengths so they have no color (rather as > a guinea pig is too stupid to have any honor), and they don't spin one way or another. Note that elementary particles have (behave as if they have) angular momentum in their rest frames, so it's not crazy to say they're spinning. And strange particles are indeed strange, and the people who found the charm quark were almost certainly charmed by it. The term "color" is a stretch, but it does reflect the important fact that combining all the colors gives you something without color.