Originally Posted by
Farsight
Then ask yourself this: in low-energy proton-antiproton annihilation to gamma photons, where does the strong force go? Oh, and the $64,000 dollar question is this: The strong force keeps a proton together. What keeps an electron together?
Once again, it's the Farsight-style argument-by-insinuation.
"Look at this! Look at that! Betcha never asked yourself THAT before! Think about it and you'll agree with me on your own in no time."
Except---no we won't. You've been posting this for years and you know how unsuccessful it has been. Did you learn anything from those years of posts and responses?
A proton-antiproton pair is
net neutral under QCD, and so are all the accessible final states. As far as I can tell this adequately answers your question---both philosophically, and intuitively, and (since QCD is a real field theory) testably. If you think there's something wrong here, you're going to have to address
these details, not ask the same question again.
The proton is a composite particle containing three quarks, and we know what holds these quarks together. The quarks are fundamental. No known theory or experiment requires any substructure "held together" inside a quark. Electrons are also fundamental. No known theory or experiment requires any substructure "held together" inside an electron. That answers the question as far as I'm concerned, until someone points out a problem in these details, which you have (still) not done.