I have known about quantum foam for some time, long enough to have factored it into my ideas about the universe.
When I first knew about the big bang, I imagined the universe oscillating. It expanded until the momentum of the initial explosion expended itself against gravity and then fell back, eventually into a big crunch which zeroed out entropy and banged again.
Now we know that the universe is not only expanding but accelerating in its expansion. This means no big crunch but it also means that the matter created in the big bang is being spread out across an increasing volume of space.
Even now they think that intergalactic space is bubbling with quantum foam albeit at a relatively low energy. I imagine that this might be because the absoluteness of the vacuum at the current level of expansion is still not very absolute.
I then imagine the future, say a trillion years from now, when the expansion has progress so far that everything is so far from everywhere else and the acceleration of expansion has made it so that intergalactic space never, ever gets any photons (the speed of expansion being greater than the speed of light), that we get to a time when there are places that go from our current vacuum density of an atom per cubic centimeter (I think I read this someplace) to an atom per cubic lightyear (or something).
Which is to say, really, really close to absolute vacuum and absolute zero.
This means that the random process of quantum mechanics now has a very extreme situation. I imagine that the bubbling of quantum foam is moderate energy because there is still plenty of matter and energy to compete with it. Then I imagine the difference in the results of the processes that create quantum foam in an extreme context a trillion years from now and guess that it would be less of a foam and more of an explosion. Something that creates a big bang.
This is a nice idea because it presents a continuous process to explain the evolution of the universe. We don't exactly have a singularity anymore than it is a singularity when a bubble bursts at the surface of boiling water. And, we don't have to worry about before and after because before there was quantum foam and after there is still quantum foam, just that the intensity has boiled away for a trillion years, or whatever, and will be back once the process continues.
It also gives some comfort to the idea of a multiverse, albeit a much less abstract one. In this incredibly tenuous future, there is no reason that two empty places have their quantum foam boil over into a big bang, could happen all the time. Even after a new universe pops up in one place, the expansion of the precursor universe would continue and one might expect new universes to explode out of the quantum foam all the time.
And it is nice because then, viewed on some ultimately grand cosmic scale, the universes themselves appear as bubbles in a new quantum foam and that makes for a nice, fractal consistency with what we see today at the microscopic, macroscopic and cosmic levels. It is all self-repeating organization and entropy, hard at work, annihilating and creating and doing it all again and again.
REF: https://bigthink.com/hard-science/nothing-exist-quantum-foam/?fbclid=IwAR1P28EHrCwCTcCaWC9ZMr-5dTY8-TmKhKM16WZ9AsCynUvnAb7kQQKYBbg