I agree totally with the OP, we are definately INSIDE something. But something very very small I think, and yet extremely advanced, atleast to advanced for us to convey. Depending on the perspective, I can imagine us as tiny cells, acting just like cells do. Dividing, Expanding etc etc. And if we expand that a little, we are cells on a big living organism, Gaia.
Sadly, many of us, the "stronger" cells are wiping us normal cells out, spreading exactly like cancer. Exactly acting like cancer! Dividing uncontrollably, Mutating ourselves and our surroundings, building unnatural structures/buildings(melanoma), roads, wiping the trees etc. Killing our host-organism Gaia, just like cancer. Thats what happening now, but thats a little sad perspective. But its a reocurring thought I get during some mystical states.
A even furthur away perspective is like some above poster mentioned, is atoms. I can somehow relate to that, Ive thought in the same patterns. I think some aspects of the universe really look atom-like. Planets(electrons?) rotating around a sun(atom-core) etc etc... No one has been into the sun so who knows how much it ressembles a close atom-core with quarks and such stuff, and even on quantum-levels...
So yes, we are definately inside something, But why, and What??
Anyway, I will stop my rambling, I just wanted to share some thoughts on a subject I also tend to think alot about.
Im no physics-genious or anything, so facts may def. disprove my thoughts, no doubt about that
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Keep your eyes at the skyes mates!
Sincerely, DeMenTera
"Disclaimer: Everything I say is a lie, or insane ramblings. Oh, and dont mind the bad spelling, Im a severe dyslectic! ;P"