Warning, you're talking to an ex particle physicist. First, LHC doesn't test the composition of most of the things you mention - I'll highlight leptons which are fundamental. That's why it's call the "large HADRON collider". Colliders are designed as specific 'microscopes' which can look at a class of phenomenon.
In any regards, I don't know what you are saying other than it sounds like pea soup. You are saying we know what quarks are, but we don't know what space-time is, but that isn't true. We know how quarks act, just as we know how space-time acts. It binds planets together, it is a mental representation of a gravitational field, which we can observe. Just as we can observe the strong force.
Look, general relativity (GR) is one of our most verified theories. The next better verified theory (to the highest precision) is QCD (has to do with quantum mechanics). You're getting slippery around the words you are using, but to say that we know GR/space time less than we know (say) the strong force simply isn't true.
Oh really, how delightful
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I do love talking to people who have worked in the field. You must have some interesting stories to tell about the theories and experiments you worked with. I'd be all ears if you were interested in sharing.
Well, all I know is I've seen studies from the LHC that documented the contents of a proton (2 up quarks, 1 down quark). It detailed neutrons as well I believe. I didn't say that the LHC probed the contents of leptons, that would be redundant being that leptons don't have a complex structure like atomic nuclei.
If we know what space-time is as well as we know what a hadron is, then what is it? Is it made out of particles? Is it an M-brane? Is it a field? If you are saying space is synonymous with gravity, then why say there is space? Aren't gravitons supposed to be the mediators of gravity? Then in that line of thought, wouldn't space be a field of graviton particles?
General Relativity may be one of the most verified theories, but that doesn't mean in a thousand years from now it's still going to hold up. A thousand years from now, the Quantum Foam theory is probably going to be thought of in the same way we regard the theory that the earth was flat. We know next to nothing. Yes, we know how to make a laser or a light bulb, but we don't understand what the universe is, how it got here, why it's expanding, what time is, if time travel is possible, how life started, what consciousness is, etc. We seem to know something about the little questions, but not much at all about the big ones. So really what I'm saying is that it's funny how scientists act like they have the answers to everything, when in fact they don't. I also think that the scientific community should reassess its fixation on a few very far-out ideas; such as the multiverse theory. It just seems like people are making things up anymore.