And if so, can we observe a difference in the electron scattering cross section with transversely polarized VS longitudinally polarized protons? P.S. Let me make my question more precise. Consider ...
I believe the quarks would flip the proton's internal charge, reverse the spin of the proton, transform into another flavor, and then become unconfined and free.
In Landau and Lipshitz's introductory book on Quanum Mechanics, "Quantum Mechanics Non-Relativistic Theory, Third Edition: Volume 3", chapter XIV (page 433 in the edition on Amazon) is "Addition of ...