One theory that I like is that the universe is built in our perceptions
I not only like that idea, I believe it. I hold that our experience, hence, our universe is an out-picturing of the content of our consciousness. In other word, believing is seeing, not the other way around. Everything is an idea within consciousness. There's really nothing out there. Reality (heavy word) is merely a set of ideas each of us hold close to the core of our being ("being" used as a verb).
It's interesting to ponder dreams. They're sort of a microcosm of the creative principle that everything material is an idea within THE consciousness out-pictured as form. Our mind creates a bubble of time and space that only exists as an idea and perception of our sub-conscious. In that dream bubble of space and time, matter is formed, thoughts and ideas, action, feelings are triggered. Our experience is no less real in the dream than it is in our waking experience. Usually quite a bit odder from an awaken perspective, but no less real. It sort of adds a different twist on "created in HIS own image". Maybe imagination would be a more meaningful term, or not.
I've been to Tehipite Valley many, many, many times and felt the struggle to get there; the grandeur of the valley opening up before my eyes, etc. in the dream reality. This year, I get to have those experiences in the TV of the waking reality.
Disclaimer:
I haven't been smoking/drinking anything and I'm not off my meds and the above is the opinion of the poster and does not necessarily reflect the views of HST or any government agency, its agents or the POTUS

If you don't know where you're going, then any path will get you there.