I don't mean to be rude but you got a great deal of this patently incorrect.
Metaphysics is the primary stuff of Philosophy. Meta- does not refer to existence, it means "referring to itself". Metaphysics means you're considering abstract stuff, first principles that don't truly "exist" in reality because they're considered at a level "beyond" mere existence. Being, substance, time, cause, identity and property are things that are analyzed with metaphysics. One of the most famous questions in Philosophy, "what is the meaning of life?" is a derivative of the metaphysical question "what is meaning? what occurs when something "has meaning"?".
Physics is a branch of science concerned not with things that exist, but how things move and interact. (Existence is a separate branch of philosophy called Ontology, "the study of what is, and existence", not to be confused with Epistemology, "the study of knowledge and what we can know".) Ghosts and Telepathy would fall under the speculative concerns of Paranormal activity. Since there is extremely little that can be done in the way of empirical science regarding paranormal activity, it remains well outside the realm of physics.
You're mistaking the Schrödinger's Cat Paradox (a physics analogy) with Impossible Objects (a logical category). Other impossible objects include square circles, married bachelors, weights too heavy for an all-powerful being to lift, and skylight windows too strong for Batman to jump through.
Schrodinger's Cat is an analogy used to describe Quantuum Fluctuation, whereby subatomic particles can exist in multiple locations in spacetime, until they collapse into single locations by being observed (implying looking at things is actually a way of interacting with them). The Map-Is-Not-The-Territory breakdown of the analogy is similar to how Kinetic Theory does not describe that atoms are actually tiny balls moving around and colliding, but simply as a mental picture to demonstrate the sub-molecular interactions within matter.
The applicability of quantuum theory to M-theory however is negligible, since quantuum physics has little to do with cosmogeny, unless you're talking about Planck Time and the Big Bang. --Neither of which have anything to do with portals (whatever those are) or Equestria (a fictional place).
This is a bit of a blend between Solipsism and Physicalism-- both of which are Philosophical ideas which not everyone believes.
Solipsism is latin for "My mind alone" and refers to the philosophical belief that one's own consciousness is the only thing that really exists. Other things like trees, birds, human beings, sensory experience and time are just things being fed to their consciousness by some unknown and unknowable source. It might very well be on this view that one could actually just be a brain in a jar being stimulated by a very powerful computer. The big shot to the foot of this idea is that everyone you ever meet will argue with the same strenuousness as yourself that their consciousnesses exist with the same level of reality as your own. It is extremely difficult to posit a reason why and how other apparently conscious beings would be lying about something like that. For that reason, Solipsism doesn't get very much traction in modern philosophy, though it makes its rounds in popular culture, like the "what is real" quotation by Morpheus in the movie The Matrix (1999). Solipsism was effectively defeated by Descartes in Discourse on the Method (1637) with his famous proposed thought "Cognito Ergo Sum": "I think, therefore I am".
Physicalism is not so easy to summarize because Physicalism vs. Substance Dualism is a hotly contested matter of Philosophy of Mind right now. In short, Phyiscalism says that 'the mind' or 'consiousness' is essentially an illusion caused by the signals inside human brains. Substance Dualism says that 'the mind' is a self-existing entity which might exist independently of matter-- thus one's mind might persist (somehow) even if the matter of one's body was destroyed. There's a great deal of pro-- and con-- to both views, but it should be sufficient to say no one is clearly right or wrong about the question.
In summary, the accuracy of your answer here is entirely dependent upon how "real" one ascribes the projections of their own imagination.