Here is an article about Prof Donald D Hoffman's theory of reality that considers what we now know in physics when considering what is real. I love philosophy, metaphysics, physics, cognitive science and neuro-science. This article compacts it all, almost way above my head, but dig your way through.
I think somewhere in the article, I could come to the conclusion that conscious agents though appearing separate, could be one ..... uh oh. Maybe the ancient mystics were right (and they didn't need physics).
Here's the link.