Or maybe the science fiction writers are just a few (or more) years ahead of the physicist. I read (and write) science fiction, and have been reading about multple universes/parallel universes for years.
None of which disputes the theological content of your post.
I started reading the "greats" as far as Sci-Fi in the late '50s. It's amazing how prescient they were. Can't vouch for present day authors as it will take time to bear their theories out, but a good deal of them are capable scientific minds despite not being "real scientists".
It's amazing that so many "scientific" minds will close so tight that only that which supports their own concepts is given any credence. They will point to lack of scientific evidence while fully backing theories that are still works in progress and always "evolving" as we learn more and have to discard some of the "standard" lines of thought.
There he assumed you could create a new universe WITHIN the existing universe we know, and it could have "designer features". His Lava Lamp World pursued one such idea.
Most folks know him best from his River World series, but he had some short stories where folks "practiced at their future lives as office workers" in a sort of "pre-Heaven". Then they would be born and take it from there.