I certainly believe in the possibility of stuff beyond the "physical world," by which I assume you mean the space-time continuum of our universe.

You'd have to be a fool to not be open to that possibility, given that we have no idea what or why anything exists, nor what might exist outside of this universe.

If you look closely, the physical world cannot be found. There is only this present moment. Past and future are memory and fantasy arising in this present moment. The couch that I am sitting on does not exist as a couch, that is a mental label. There is just causality rippling in this present moment.