People recently have been positing that the big bang occurred as result of a black hole (i.e. black hole sucks up more and more material, gains more mass, until it explodes in a big bang into a new universe).
My question is, if this is the case, is there (1) another universe "above"? And is there another universe "above" that eternally? Or is it (2) more the case that our existing universe expands, it reaches an edge of maximum expansion, and a gravity-like counter force causes it to collapse in on itself, until it again repeats the big bang process (eternal recurrence)?
Take the first example. If the conditions at the bottom of two black hole "singularity"s are the same - you would expect parallel, equal universes to be generated each time. Copies of the same universe generated over and over again with each black hole. If the conditions were slightly different (i.e. one black hole has slightly more quarks than another), you might have a "parallelish" universe arise where with slightly different initial conditions you experience vastly different results (chaos theory, small changes in initial conditions).
If the second were true, given no energy / mass would be leaving the system, you'd expect the same situation to recur eternally. The "universe" as we experience it would be bounded on one side in time by the "singularity" and on another side in time by the "edge" (the point of maximum expansion) creating a fixed, spatiotemporal object. Why does this spatiotemporal universe marble exist and what exists outside of it?
I can't wrap my head around this. Which scenario is more likely? Does any of this make any sense? If the answer is "we don't know", do you think there is a way to ever answer these questions?
It seems like we're trapped in some sort of strange, fractalian experiment.
[1] - https://www.youtube.com/@pbsspacetime/search?query=black%20h...
But it is not that black holes explode into the universe, it is that the knowable universe is in a black hole. like I said science fiction, the part I like is it explains(It does not really, again I repeat no actual science) why time as a dimension only goes one way. just like once you pass the event horizon of a black hole there is no "out", you have lost half a dimension, inside the event horizon we call the universe, the half dimension we are missing is the out direction of the dimension we call time.
That's a strong no (for any sufficiently complex physical setup with moving parts, falling glasses won't shatter the same way twice).
Two things here are relevant:
1) Lorentz (Butterfly) and Smale (Horseshoe Map) both proved that in some physical systems you can always find initial conditions that are very close (for any arbitary epsilon of "close") that none the less end up far away from each other as time passes.
ie: Unless the initial starting points are absolutely precisely identical without question, then "close enough" isn't good enough to guarentee an identical outcome in the presence of "strange attractors"
2) The Uncertainty Principle tells us that at a fine enough grain (within a certain epsilon) initial conditions are like jelly - you cannot nail them to the wall and declare two systems identical.
On the contrary, due to the expansion of the universe, stuff tends to move further and further away from other stuff over time, so the chances of things colliding with a black hole get smaller and smaller with the age of the universe. At some point all black holes evaporate (at least according to current theories) because so little stuff falls into them that the tiny amount of hawking radiation that they radiate is enough to evaporate them over trillions of years.....
Also, the question whether "a universe before the big bang" (if such a thing exists) is "the same" as ours, or "different", doesn't really make sense. If you take all matter in the universe, heat it up so that only high-energy radiation is left, and then let it "create another universe"... . how would you define if it's "the same" or "different"? All matter has been removed and recreated. It's similar to the idea that you take a ship, any ship, and piece by piece replace every single part of the ship one by one. At the end, is it still the same ship or a different one?
To take a more traditional scientific stance, asking "what happened before the big bang" is meaningless because time didn't exist, it was created by the big bang. It's tricky to wrap your head around the concept, the same way that it's tricky to wrap your head around the concept of an "expanding universe" that seems to expand "away" from us in every direction, yet we are not in the center of it. Or that the universe might be infinitely large or even wrap around, yet we will never know because we can only ever "look" 14 billion light years far into the universe. It could be that after travelling for 20 billion light years we wouldn't reach the end of the universe (because it has no end) but instead land back on earth.
Some questions can never be answered because of physics. They will forever be unknown because answering them either makes no sense, or none of the answers you could give could ever be verified/falsified. So: does asking these questions even make sense?
I tend to think we are a hologram generated from the surface of a black hole, and yes, probably black holes all the way "up".
Of course, it still leaves the question of the first black hole, and why anything at all instead of just nothing.
As best I understand, he's proposing that the universal will not ever fully collapse into a black hole. On the contrary, it will continue to expand and diffuse, eventually reaching a state in the far future—and here is where the details exceed my understanding—somehow physically/mathematically identical to the conditions that were present at the Big Bang. Or in other words, if you run time out to an infinity in one direction, it sort of "wraps back around" on itself.
Melodysheep (the creator) has some great stuff on the topic.
Whil in reality it’s nothing but purely theoretical mathematical models operating on such a high level of abstraction and uncertainty that it is even hard to decide whether some of your questions make any sense or not.
It's turtles all the way down.