Big Bang, the start of the universe, and CMBR
Discussion
Forgive my non-physicist questions on this, but we keep hearing that before the BB the universe was compressed into a tiny area. Where was that area? If we can observe galaxy GNZ11 13.8 billion light years away, and that galaxy was formed relatively shortly after BB, and the light from that galaxy is red-shifted, so it is travelling away from us, and presumably also away from the site of the BB, does that mean that the BB happened in between us, and that galaxy?
If we look at galaxies diametrically opposite the GNZ11 from our perspective, are they moving less quickly away from us because we and they are moving away from the BB site in the same direction?
And, and, this Cosmic Microwave Background Radiation, said to be an echo of the BB, why hadn’t it overtaken us and vanished by now? Radiation must travel faster than galaxies. If I am a duck on a pond and someone throws a pebble in, the ripples radiate out and go past me. They don’t hang around to be measured years later.
Thanks.
louiechevy said:
There is no spot nowhere existed until the big bang happened and expanded into the universe, so everywhere you look is where the big bang happened thats also why we can still detect the background radiation as its all around us.
Cheers. On delving it seems most believe it was a big stretch rather than a Big Bang in the sense of an explosion. There does seem to be uncertainty as to whether the universe is finite, or infinite. If it is finite, you would expect it to have a centre of mass, which you might consider the centre of the universe and so the very small dense thing that expanded might have ‘been’ there; on the other hand, the universe may be infinite, with no centre of mass, but in that case why does the night sky look mostly black (infinite number of stars = light universe).....eharding said:
Excellent! She must have read my mind. With the light most of the stars even in this galaxy are so far away that the light can't get to our eyes because its blocked by all the gas and other things in its way, imagine standing in a wood you could see someone stood next to you but as they walked away all the trees would hide them from your view.
louiechevy said:
With the light most of the stars even in this galaxy are so far away that the light can't get to our eyes because its blocked by all the gas and other things in its way, imagine standing in a wood you could see someone stood next to you but as they walked away all the trees would hide them from your view.
If the inverse is infinite, how can it have been made only 13.8 billion years ago? That is not enough time, even at light speed, to expand to infinity. If it is not infinite, it must have a centre of mass, no ?
It’s not a dumb question at all. Intuitively, we are surrounded by space and presume and are told that this space stretches out uniformly in every direction. It is therefore natural to think of this space as having form and a centre. But with the Universe this space is everything, and nothing exists other than it. There is no outside of it as there is no before it (although I don’t believe time exists but that is a another subject).
Just as you can’t have a middle of a set of numbers that stretches to infinity, there can be no centre to an infinite (or apparently infinite) space.
We are the Big Bang. The Big Bang was just the Universe, everything that exists, at a very young age. It became you and me and everyone and everything that you or anyone else will ever see. We are the Big Bang, expanding into infinity.
For all intents and purposes, you (as the observer) are at the very centre of everything you see. But don’t let it go to your head, as so is everybody else.
Just as you can’t have a middle of a set of numbers that stretches to infinity, there can be no centre to an infinite (or apparently infinite) space.
We are the Big Bang. The Big Bang was just the Universe, everything that exists, at a very young age. It became you and me and everyone and everything that you or anyone else will ever see. We are the Big Bang, expanding into infinity.
For all intents and purposes, you (as the observer) are at the very centre of everything you see. But don’t let it go to your head, as so is everybody else.
Ayahuasca said:
louiechevy said:
With the light most of the stars even in this galaxy are so far away that the light can't get to our eyes because its blocked by all the gas and other things in its way, imagine standing in a wood you could see someone stood next to you but as they walked away all the trees would hide them from your view.
If the inverse is infinite, how can it have been made only 13.8 billion years ago? That is not enough time, even at light speed, to expand to infinity. If it is not infinite, it must have a centre of mass, no ?
TX.
Ayahuasca said:
If the inverse is infinite, how can it have been made only 13.8 billion years ago? That is not enough time, even at light speed, to expand to infinity.
If it is not infinite, it must have a centre of mass, no ?
To give you an idea of just how slow the speed of light really is. (Do a lot of fast forwarding)If it is not infinite, it must have a centre of mass, no ?
https://www.youtube.com/watch?v=2BmXK1eRo0Q
MiseryStreak said:
It’s not a dumb question at all. Intuitively, we are surrounded by space and presume and are told that this space stretches out uniformly in every direction. It is therefore natural to think of this space as having form and a centre. But with the Universe this space is everything, and nothing exists other than it. There is no outside of it as there is no before it (although I don’t believe time exists but that is a another subject).
Just as you can’t have a middle of a set of numbers that stretches to infinity, there can be no centre to an infinite (or apparently infinite) space.
We are the Big Bang. The Big Bang was just the Universe, everything that exists, at a very young age. It became you and me and everyone and everything that you or anyone else will ever see. We are the Big Bang, expanding into infinity.
For all intents and purposes, you (as the observer) are at the very centre of everything you see. But don’t let it go to your head, as so is everybody else.
Because this thread doesn't make my head hurt enough... lolJust as you can’t have a middle of a set of numbers that stretches to infinity, there can be no centre to an infinite (or apparently infinite) space.
We are the Big Bang. The Big Bang was just the Universe, everything that exists, at a very young age. It became you and me and everyone and everything that you or anyone else will ever see. We are the Big Bang, expanding into infinity.
For all intents and purposes, you (as the observer) are at the very centre of everything you see. But don’t let it go to your head, as so is everybody else.
... can you expand on that??
Terminator X said:
Apparently that is the "observable universe" with the actual universe being an unknown amount bigger. We will only ever know the OU. Head hurting, must lie down.
TX.
The fun thing that keeps rattling around in my head is that if the OU is 13.8B LY in one direction and the same in the opposite direction then those points in space are further apart than it is possible for them to be given they can only move away from each other at a maximum of C.TX.
While nothing can be more than 13.8B LY away from anything else every point in space can 'see' 13.8BLY in every direction...
Then of course they may not be moving at C, but rather the space between them is expanding.
Toltec said:
The fun thing that keeps rattling around in my head is that if the OU is 13.8B LY in one direction and the same in the opposite direction then those points in space are further apart than it is possible for them to be given they can only move away from each other at a maximum of C.
While nothing can be more than 13.8B LY away from anything else every point in space can 'see' 13.8BLY in every direction...
Then of course they may not be moving at C, but rather the space between them is expanding.
The way I think of it is a balloon being blown up from a point. The furthest you can be away from something is the other side of the balloon, there is nothing inside or outside the balloon, just the balloon surface.While nothing can be more than 13.8B LY away from anything else every point in space can 'see' 13.8BLY in every direction...
Then of course they may not be moving at C, but rather the space between them is expanding.
Terminator X said:
I could be wrong but my simple view is that the Universe is like a pendulum, it swings in an arc albeit always going back to the centre e.g. the Big Bang. Anyone else had that theory 
TX.
Yep - lots of physicists. Apparently it depends on how much dark matter there is. From stuff we can see, the universe should just keep on expanding. But if there is a lot of heavy stuff we can’t see, then the gravitational force from this could pull everything back together- possibly as a singularity black hole.TX.
Gassing Station | Science! | Top of Page | What's New | My Stuff