Quarks and gluons interact so frequently that it makes little sense to regard each color state as a unique fundamental particle. These interactions also do not change any of the quarks' other properties. Correct?

For quark flavor, however, switching one for another also changes the mass. This is due to the Higgs mechanism. Two quarks in a doublet otherwise correspond to different weak charge states, similar to a color transformation in QCD. Strangeness and charmness represent the weak color in the 2nd generation, for example. Is this so?

Thank you for being patient with a physicist who is curious far beyond his own level of mastery!


1 Answer 1


To add some of my own understanding, there is a difference between the quark states we usually refer to (up, down, etc) and the "weak states" I was trying to get at.

The six defined quarks make a basis for a vector space wherein all superpositions of these can exist. The named states are eigenstates of the mass (or electrical charge) operators. To my best knowledge, the operators are used to probe the wavefunction in order to return the desired value.

Now, during a weak interaction or decay, a transformation acts on the wavefunction, but it does not act upon the mass/charge eigenstates mentioned. It acts on another chunk of that superposition blend that all particles find themselves in. To shift focus from the mass states to the weak states, basically another definition of the six quarks, you multiply in the CKM matrix.

Again, the Higgs field is to blame.

My best understanding is that the doublet components in this modified basis are what I was looking for. Being the weak eigenstates, these correspond as much as possible to the quark color states for QCD. Though it's clearly more complicated than that.


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