Are virtual pions necessary to mediate the residual strong interaction?

Question

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.

Answer 1

You seem to be misunderstanding what the effective theory with the residual nuclear force between hadrons mediated by pions is: It is an effective theory which is a good approximation of the underlying nuclear force between quarks mediated by gluons. It is not that one of these is correct and the other false, or that they represent two different forces - they are both descriptions of fundamentally the same phenomenon at different levels of detail.

You cannot detect virtual particles mediating an interaction anyway - since a virtual particle is just a mathematical fiction arising from the diagrammatic description of our perturbation series used to compute QFT amplitudes, it does not "exist" in the sense that it could be detected.