No one knows, it's unlikely we ever will. There's stuff and that's why you can even ask this question. If there wasn't anything, you wouldn't be able to ask anything. It happened, so now we have to deal with it.
Ex physicist here: Fucking no clue, but here's two neat ideas
Because there has always been things. Basically it's entirely possible the universe just kind loops around given enough time, there are a few really interesting ways to do this but the classic one is where the big bang reverses and there's a bug crunch before a new big bang. That's not very likely based on our observations, but there are other more mathematically complex ways to have a cyclical universe, and they don't necessarily require having a defined beginning.
Because nothingness is unstable. Basically, if there's a concept of nothingness, no energy, particles time or space, but it's possible for little universes to occasionally exist and disappear really quickly, then it's possible that our universe suddenly popped into existence, got really fucking big before it could disappear again and then got stuck existing. This is based on the highly advanced area of physics called making a wild fucking guess.
I'd say most likely that we'll have to be satisfied with that not being a question that can be answered. Much in the same way that we can't answer the question of why the laws of physics look the way they do, we can just describe what they currently are.
There's a third option: Black holes create new universes through some as yet undiscovered process. Then your existence just becomes a statistical eventuality, as do every other life that you could ever live.
There's a fourth option: every reference to the mystical properties of black holes on lemmy creates new universes through some as yet undiscovered process. Then your existence just becomes a statistical eventuality, as do every other life that you could ever live.
Yeah that's what I was getting at, all we can do is guess. It's pretty easy to realise it's impossible to answer scientifically, anything that could have any impact on our universe must necessarily be part of it and so cannot tell us anything about what came before.
No one knows. I really want to know, but the current understanding takes us back only to the big bang. Not why it happened or why anything exists at all.
The Anthropic Principle is at work here.
If nothing existed we wouldn't be here to ask why it exists.
Here's some reaching: There's the theory hypothesis that our universe is the inside of some construct in a higher universe* that is similar to if not actually a black hole.
In our universe, time and space inside a black hole are causally disconnected from the outside so there can be a defined beginning without there needing to be time continuity across the event horizon. It's often said that time and space switch places inside a black hole, which could mean that our time is relative to space outside of the universe. This hurts my head to think about. Almost like our time dimension runs sideways relative to whatever was "before".
* As to whether this is turtles all the way down / universes all the way up, we'll probably never know.
That's not a theory; not in the scientific sense. That's just someone being creative, we have no way to prove or disprove it, ergo it's as useful as explaining everything by God.
The universe feels like a pretty whimsical place, so why not? Might as well try it out. If it sucks, you can always let everything crash into a singularity and start over.
Because when there's nothing there is literally no meaning. Prior to the Big Bang there was no Entropy, no Time, no Matter or Energy. You cannot really discuss what happened then because it would be nonsense. You can't even ask 'how long before the BB did the nothing exist?' because there was no time, so the answer is like dividing by zero. The BB brought all that into existence so by necessity anything must exist for your question to even have meaning.
To answer your question more directly: because nature abhors a vacuum (even though there was no vacuum before the BB because that would have been a 'something').
As much consensus as there can be. The BB is defined as being the event that brought everything into existence and so there's no point in debating something that cannot be tested.
Because, to maintain "nothingness" the omniverse must balance matter and anti-matter.
Well, that became unbalanced because of random fluctuations.
So theres a pocket of matter and anti-matter didn't annihilate for some reason, I call it "plot armor" reasons, and that separated from each other forming 2 regions of space.
So the region of positive-matter, through randomness eventually formed our universe.
The region of anti-matter probably formed its own anti-verse
Ok I'm bullshitting, I'm not a scientist and I made up the whole thing mmkay? That's my amateur explaination of the universe. Fight me.
But like, philosophically make sense.
How do you get something from 0?
0= [+1] + [-1]
See? That's my mathematical proof.
Its my version of E=MC², but with the creation of the universe and anti-verse.
There isn't any anti-verse, normal matter won for reasons still unknown, because the big bang should have created an equal amount of matter and antimatter. So plot armour is a good enough explanation for now.
But since there was less antimatter, it was all annihilated.
That still doesn't answer OP's question, though, you can go further - why did big bang create more matter? Why did big bang happen? And if you one day manage to answer that, you'll have to ask why the thing that caused big bang happened?
(Again, I'm not doing a scientific explanation, this is a philosophical explanation)
There is the same amount of matter and antimatter, but some mysterious energy propelled them to separate with a distsnce in between them. This is how the universe and the anti-verse are stable. But eventually, these two different "universes" will collide and annihilate each other again.
I'm more about wondering about after everything now. When everything stops expanding and all the energy is gone, does everything collapse and cause another big bang? Has this happened before?
Is this "multiverse" many of us wonder about really just this same universe in different incarnations? Can any of these incarnations really be said to be "before" or "after" each other?
If the universe/big bang didn’t exist, would numbers conceptually still exist? i.e zero is still zero regardless of whether any matter exists, right?
If there is no form of existence in which math doesn’t exist, then everything ultimately exists necessarily. It has to exist, as a result of being derived from the infinity of math.
Everything is just math, and it therefore has no option but to exist.
We wiki never know. My take, which is not a thing one can prove or disprove, is that something that don't actually exist needed something to exist in order to love. My answer is love.
People say shit like this, but it's just not true. If darkness is the absence of light, then it's dark so long as there isn't light. If you observe a universe where there are no photons, it'd be dark everywhere. (it'd also not have the EM force, but let's put that aside for now.) You can have darkness without light, but if you aren't aware of light, then you simply wouldn't have a word for darkness; you are confusing the conceptualization of thing with the thing itself. In my circles, we refer to this fallacy as confusing the map and the territory.