Please correct me if I’m wrong in understanding big bang, I understood that there was nothing in the beginning and everything was formed all at once, hence the light from the farthest will take billions of years to reach us to see it’s present moment and so why is matter limited, honestly feels like a computer simulation since everything is limited in nature.
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> I understood that there was nothing in the beginning and everything was formed all at once
We don’t know what was there “before the big bang” (which is already ill defined because the big bang is the beginning of time as we know it), but having the universe being created ex-nihilo creates more problems than solves.
So there most probably was something that caused the Big Bang, the universe as it is today probably didn’t just “appear out of nothing”. What that was and what laws of physics did it obey? Was there time, the way we describe and think about it now? Maybe, maybe not.
But “we don’t know” is a far cry away from “there was nothing”.
Regarding the rest of your question, I don’t know, but we can’t actually see light as far back as the big bang, because the universe was opaque at the time and no light from before then has been allowed to reach us without being intercepted by something else.
The first time this has happened is at so called recombination, which happened ~380,000 years after the big bang. At that point the universe was infinite and since light travels at a finite speed, we can’t see further away than that.
As time goes by, light from the moment of recombination we see comes from further and further away, because more and more time has passed.
That’s why we can only see a finite part of the universe and it’s getting bigger as time goes by.
> I understood that there was nothing in the beginning and everything was formed all at once
We don’t know what was there “before the big bang” (which is already ill defined because the big bang is the beginning of time as we know it), but having the universe being created ex-nihilo creates more problems than solves.
So there most probably was something that caused the Big Bang, the universe as it is today probably didn’t just “appear out of nothing”. What that was and what laws of physics did it obey? Was there time, the way we describe and think about it now? Maybe, maybe not.
But “we don’t know” is a far cry away from “there was nothing”.
Regarding the rest of your question, I don’t know, but we can’t actually see light as far back as the big bang, because the universe was opaque at the time and no light from before then has been allowed to reach us without being intercepted by something else.
The first time this has happened is at so called recombination, which happened ~380,000 years after the big bang. At that point the universe was infinite and since light travels at a finite speed, we can’t see further away than that.
As time goes by, light from the moment of recombination we see comes from further and further away, because more and more time has passed.
That’s why we can only see a finite part of the universe and it’s getting bigger as time goes by.
This is a variant on Olbers’ paradox: if the universe is infinite, why is it dark at night?
This is a variant on Olbers’ paradox: if the universe is infinite, why is it dark at night?
We actually don’t know if the universe is infinite or not.
We noticed that galaxies tend to all be moving further apart from each other over time. If you play time in reverse, they appear to be getting closer together. And we’re able to play time in reverse because light takes a long time to reach us if it’s coming from really far away. So when we observe stuff that’s really far away it’s like looking far into the past.
But…. There is stuff that is soooo far away that the light will never reach us because the space between us is expanding faster than the light can travel the distance. Anything past this distance has exited the observable universe and we can no longer see it forever.
Thus, the observable universe has a finite distance that can be measured and is not infinite. We can only observe stuff that light can travel the distance between faster than the space expands.
But everything outside the observable universe? We’re not entirely sure how big that is. Could be infinite, might not be infinite. We don’t have a way to prove it yet.
There is the cosmic microwave background radiation which is light that appears everywhere and thus seems to be good evidence for a big bang type event (since if everything originated at a single point that would explain the light being everywhere). But that doesn’t tell us if the universe is infinite or not (what if the single point was infinite).
We actually don’t know if the universe is infinite or not.
We noticed that galaxies tend to all be moving further apart from each other over time. If you play time in reverse, they appear to be getting closer together. And we’re able to play time in reverse because light takes a long time to reach us if it’s coming from really far away. So when we observe stuff that’s really far away it’s like looking far into the past.
But…. There is stuff that is soooo far away that the light will never reach us because the space between us is expanding faster than the light can travel the distance. Anything past this distance has exited the observable universe and we can no longer see it forever.
Thus, the observable universe has a finite distance that can be measured and is not infinite. We can only observe stuff that light can travel the distance between faster than the space expands.
But everything outside the observable universe? We’re not entirely sure how big that is. Could be infinite, might not be infinite. We don’t have a way to prove it yet.
There is the cosmic microwave background radiation which is light that appears everywhere and thus seems to be good evidence for a big bang type event (since if everything originated at a single point that would explain the light being everywhere). But that doesn’t tell us if the universe is infinite or not (what if the single point was infinite).
People say that the universe may be a computer simulation because that’s the extent of our technological understanding. Before people have said it’s a play, a movie, etc. Now people say a computer program/simulation. The point is that people have always had a feeling that there is more to the universe than this material world. The computer simulation “theory” is not a novel idea. Read the vedas. Stufy Buddhism. There are literally thousands of years of brilliant philosophy on the subject.
People say that the universe may be a computer simulation because that’s the extent of our technological understanding. Before people have said it’s a play, a movie, etc. Now people say a computer program/simulation. The point is that people have always had a feeling that there is more to the universe than this material world. The computer simulation “theory” is not a novel idea. Read the vedas. Stufy Buddhism. There are literally thousands of years of brilliant philosophy on the subject.
Because the speed of light is finite and the universe has only existed for a finite period of time (13.8 billion years). This means that light has only had 13.8 billion years to reach us. Light from any part of the universe more than 13.8 billion light years away from us *when that light was emitted* hasn’t had enough time to travel and reach us yet.
Because the speed of light is finite and the universe has only existed for a finite period of time (13.8 billion years). This means that light has only had 13.8 billion years to reach us. Light from any part of the universe more than 13.8 billion light years away from us *when that light was emitted* hasn’t had enough time to travel and reach us yet.
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