What is the reason that the color properties we call red, green and blue have become tied to quarks, while what we call anti-red, anti-green and anti-blue has become tied to anti-quarks? Do note that I am NOT refering to the names (you can call any color value anything you want, after all), but the actual properties! Whatever the color Red really is, could that property have been tied to anti-quarks instead of quarks during the formation of the big bang? Or is there something special about the property we call Red that means it could only, ever, have become tied to quarks, and not anti-quarks??
Asked
Active
Viewed 479 times
2 Answers
2
(Do quarks have) color charges because of something?
Boris Struminsky is though to be one of the first to postulate an additional quantum number for quarks, allowing for the $\Omega^-$ hyperion (comprising three strange quarks) to exist without violating the Pauli exclusion principle. Color charge was, hence, introduced as solution to this problem.
Experimental evidence from $e^+e^-$ annihilation shows there to be three color charges.
Can quarks have anti-colors?
A basic tenet of QCD is that quarks must combine to be colorless. If quarks could gain anti-color we would expect to see quark-quark pairs but we don't.
thodic
- 258
0
If you take some quark flavors to have color charge, $\psi_f\to U\psi_f$ with $U\in SU(3)$, and some others to have anti-charge, $\psi_g\to U^*\psi_g$, then the lagrangian $$ {\cal L}=\sum_{h=f,g} \bar\psi_h i\gamma^\mu D_\mu \psi_h $$ will not be gauge invariant, because $D\to UDU^\dagger$. In other words, this theory violates conservation of color.
Thomas
- 19,250