Here is an analogy to help explain what I am asking. I throw a rock into a pond. The ripples moving out and away from the center represents the Big Bang for our universe. If someone else throws a rock in at the other side of the pond, another Big Bang would occur, creating its own space time.
Is this possible? Could another Big Bang happen?
For the second part of the question lets assume that it can and did happen, and that the laws of physics for the second universe are the same as ours.
What would happen if the two universes expanded and collided? Would they just merge?
A number of scientists have talked about the concept of new universe formation by a variety of mechanisms. Brian Greene’s The Hidden Reality: Parallel Universes and the Deep Laws of the Cosmos details many of these. He takes nine different mathematical starting points and shows how each could result in multiple universes. They are not all independent, either. Some of the multi-verses can spawn other types of multi-verses. Despite what I just said it’s a very readable book and I highly recommend it.
What happens with a second (and third, and tenth, and millionth) universe depends on how it is formed and how it develops. Usually, a new universe implies separateness. They can never interact. But that may not be absolute.
Right now, these are all theoretical mathematical constructs. They might not even be possible. Or they all might. When it comes to the entire universe you can legitimately say: it’s complicated.
I read something a while back that said that differences in background radiation in the universe could point to other universes having “glanced off” our own. The idea was that the background radiation should have been equally dispersed otherwise.
I’m sorry I can’t be more clear, as I’m working from memory. It sounded like an interesting theory, however.
Look at this representation of the universe:
It has been proposed the wispiness is because galaxies are pushed away from the center of the voids and congregating on the edges, like foam on large bubbles.
On this basis, I can believe the universe started with a lot of Medium-Sized Bangs.
The problem with this analogy is that the Big Bang wasn’t really like a rock being thrown into a pond. The bang wasn’t an explosion that happened somewhere. The BBT describes the universe’s overall density decreasing. The Big Bang is happened everywhere and continues to happen everywhere.
A better analogy would be to have a lake of boiling water that’s cooling down. There’s no particular spot the lake is cooling down in because it’s happening uniformly everywhere.
Now, that isn’t to say that there couldn’t be some other lake nearby which could interact with our original lake. At this point we can only make wild guesses as to what would happen, because while this other lake could be made of water like our own, it could also be made of oil or cough syrup or mercury. The interaction between them would depend on the properties of this other lake.
In most of the models with multiple events which could be described as “big bangs”, it would be absolutely impossible for the resulting universes to interact with each other. In fact, in the most mainstream such model, our Universe actually resulted from the slowing of the expansion of the embedding space (what most models refer to as the end of inflation). If there’s another non-inflationary bubble (i.e., another universe), the space in between us is still expanding at inflationary rates, putting us ludicrously far apart.
Can I just start by saying that I AM NOT A CREATIONIST, I believe in science.
But Physics appears in some of its branches to be at the same level of Alchemy in the Middle Ages.
I was surprised at just how much currently is theory and guesswork.
Hence the speculation about Dark Matter, Dark Energy, why the expansion is speeding up instead of slowing down etc
So my guess would be, in an infinite multiverse, where there are infinite possibilities, not only could it happen , but somewhere IS happening, has happened and will happen in the future.
Why is it surprising that at the edges of what we know about the universe, we don’t know very much about it? Science is not a neatly organized body of knowledge in which we always knew exactly how everything works. There are always fringes of our knowledge in which we have some interesting hypotheses which can’t yet be said to be confirmed.
It’s a fairly common guess that in an infinite universe everything would happen. Furthermore, it would happen infinitely many times. There are some scientists who are skeptical about this claim.
If by that you mean that there are some areas where we’re completely clueless and just making the barest of grope-in-the-dark guesses, yes, absolutely. That will always be so: It’s part of the nature of science. What separates us now from the alchemists is that we admit that we’re clueless, and have a systematic technique for pushing back the boundary of cluelessness.
Thanks for the link. Looks very interesting. Ill get a copy ordered.
I agree. In order to visualize my analogy you would need to be an observer from outside our universe. The pond would represent nothingness. The first BB would be the creation of all space time, expanding and growing larger, representing our universe. The second BB would be a separate event in the pond (nothingness) having no influence on our universe. The only connection would be when the expanding space time (ripples) intersect one another
That’s why I said lets assume the laws of physics for the second universe are the same as ours.
