yea, that is exactly how we came up with imaginary numbers which have been hugely helpful in understanding how the world works and has advanced mathematics.
you are incorrect to suggest that theoretical physics always precedes experimental physics. In fact, experimental physics lead in the subject of dark matte and dark energy..
Ether, was a suggested postulation to issues of how EM waves propagated. You are right. when a postulate is incorrect it will lead to contradictions.
"collapse in on itself" real science does not collapse o itself. for instance: Newtonian physics is accurate within certain conditions. all Relativity did was to explain how physics behaves at speeds near velocity of light . quantum mechanics explains the physics that occur at very short distances.
Plato's point of view, is inconsistent with Science and sciences' history.

particles exist and they are not limitless. (my husband has MS in physics and this is his response )