SA has left the world of science, and has entered the world of science-fiction.
They won’t give up on alternate ‘universes’ and parallel ‘universes.’ Oh yeah, and the ‘multiverse.’
This is not science.
These other ‘universes’ can not exchange information with us. We can not perceive them. So that puts them out of the realm of science, and into the realm of imagination.
Being able to perceive a thing is not the test. There are a lot of things we can't (or couldn't) perceive that are far from residing solely in the realm of imagination: The atom, the future, radio waves, the curvature of the earth, numbers, etc.
I mean, I don't agree with their thinking entirely, myself, particularly the article of faith they cling to about the Universe being a "closed system." That's "settled science" to most physicists, and its their excuse for ignoring even the possibility of a God, the God of Abraham in particular, from their thought experiments. And "settled science" is not science.
Nevertheless, more "posits" are broken on the reefs of reality than borne true, but only in their pursuit of experimentation, even when their only tools are mathematics. Most of science is eliminating the unreal.
Not a bad writer, but he misses the point about time and perception, and perhaps the scientists he describes don't see the point, either.
If what they imply is true, the "past" is all possible universes zipped up into now, and the future, the "not-happened yet" - the actual "multiverse," are all the possibilities. They might really be onto something, a better description of reality, which is all our science can ever hope to do.