The process of creating a material world, that can create beings to appreciate it, is well explained via the Big Bang theory.

Don't know is there one proof for Big Bang. The 'proofs' for Big Bang are just speculations.

So consciousness is something we cannot yet adequately describe, however we do know that it does not reside outside of the brain, many tests have determined this, and nobody is yet to prove otherwise.

To not write long comment here, I'm gonna write about it soon as I planned already. But in short there were many who experienced NDE and OBE, some people who can consciously leave their body and have OBE, people who are experts Remote viewers and many other examples. That all combined can tell there is more to it then just activity in brain.

So it wouldn't be I'm saying only someone else experiences, I had many experiences of my own, some of them I will describe in next few articles.