In relation to another question I asked recently, I was wondering if the forces between the up and down quarks of the protons and neutrons in nuclei would be sufficient to keep the nuclei bound together without invoking virtual pions as pseudo-Goldstone bosons for the residual strong interaction.
Also, a quick note on the detection of these pions via proton-proton collisions, it seems like pions would be produced anyway and that this says little about the residual strong interaction. That is, it doesn't prove that these virtual pions do indeed mediate that interaction.
Any help is much appreciated.