Imagine when someone talked to you about quantum theory, let's say, the many worlds interpretation idea, that says: the different possible realities of a quantum object crystallise into different parallel universes at the point of measurement.
What's that saying? : Quantum theory is strange?
Yes. It is. And it's hypothetical; A conjecture. It fits the facts, but it's only one of several ways to explain those facts (all of them strange, but not yet demonstrated to be impossible).
And there's the theory where particles exist in multiple states simultaneously until measured,
Schrödinger's cat?
Indeed. It comes across as absurd. But it's consistent with experimental results, in a way that intuitive classical physics is not.
OTOH, your conjectures in this thread (such as ghosts and substance dualism) are inconsistent with experimental results, and so are simply false.