Thread: Big Bang? (1st post from the new kid, Me.)

Assuming that the Universe is infinite in all directions I find our assumption that the entire universe is expanding and accelerating literally short sighted. Our VISIBLE part of infinity is doing both. Are other parts contracting? Can infinity collapse to a single point? Whats happening a million billion light years in any direction? We can't know, YET.
Take a section of rapids in any river. You'll find a HUGE variety of movements in a relatively small area. Many different forces at work. Looking at one drop of water in that stream does not enable us to predict the moments in many if any other parts does it?
Our tiny, but growing, brains have led us to many assumptions in our history: flat Earth, geocentric universe, God, etc. The Big Bang concept is, in my opinion, another shining example of this small scale thinking. Thanx for reading.

The MAINSTREAM view is that only the metric is expanding and accelerating. Basically just the amount of space between stuff.

In the past the distance between everything was less.

Now this is the mainstream view ...
The mainstream view is defined as the best theory we currently have. So while it may be "short sided" there is not a better theory out there. This is the way that makes the most sense as a complete theory. Is it absolute? Abosultely not .... but you need to be careful when questioning it UNLESS you have a complete theory that fits the observable data better that wht the mainstream theory does.

BTW I agree with you and have thought about this lots ... It doesnt make sense to me and I believe we are wrong. However I dont have a better explaination at this point.

Welcome to the board

Originally Posted by XPARATROOP

Assuming that the Universe is infinite in all directions I find our assumption that the entire universe is expanding and accelerating literally short sighted. Our VISIBLE part of infinity is doing both. Are other parts contracting? Can infinity collapse to a single point? Whats happening a million billion light years in any direction? We can't know, YET.
Take a section of rapids in any river. You'll find a HUGE variety of movements in a relatively small area. Many different forces at work. Looking at one drop of water in that stream does not enable us to predict the moments in many if any other parts does it?
Our tiny, but growing, brains have led us to many assumptions in our history: flat Earth, geocentric universe, God, etc. The Big Bang concept is, in my opinion, another shining example of this small scale thinking. Thanx for reading.

I can't see that anything is "small scale thinking" since it took some of the greatest minds to work it out over many years and even if they might be in disagreement on some issues, the overall facts gathered so far are for the most part are in agreement with reality. Working out the math to make sense of all we see and don't see on almost all levels is not in my book "Small Scale Thinking". Mysteries are meant to be solved and thanks to the thinkers who solve them we are where we are. Some one in the past once said that all is thought and answered and we have nothing else to do but live with what we have. Really ???
If what we see is small scale, then lay a big one on us.

"Small scale": The visible universe as we can see it today. Again I refer to the river rapids or how about a grain of sand on your LOCAL beach. We just can't seem to grasp infinite. We assume that what we can see is all there is and since it's expanding it must have began the expansion at some point. As the rapids have numerous variables which cause differences in the flow of the same body of water, the infinite universe has similar but endless movements. WE just happen to be in a part which is expanding. When we are able to see further than we do now we MAY discover that.
I am thrilled to have been alive to witness the expansion of the visible universe by Hubble and other means. I hope we (Humans) don't stop any time soon.

I wonder how that will benefit mankind as a whole? We sit around looking towards the edge of the heavens or curiously crunching numbers on keyboards hoping to find some sense of reality; when in reality were just hypnotized hypocrites turning away from the problems we face here and now- only capable of seeing farther with more detail thinking that warrants our search. We should get together and work out some of the real problems faced by todays world - like great minds should. All else is vanity.

One of the implications of the Big Bang is that the universe is not infinite, it has a radius of about 14 billion light years. That's a really big number, but nothing like infinite. If you want some fun things to think about, realize that the whole universe started inside the Big Bang, and is still there. The Cosmic Microwave Background started out as high energy gamma rays, and has been red shifted because we are moving away from it at nearly the speed of light. Everything in the universe is moving away from the Big Bang at nearly the speed of light, except we are inside it, so "away" has no meaning. Instead, we say that space-time is expanding.

Another really fun thing to think about is that every observer in the universe is smack in the center of the universe. If that were not true, there would be large variations in the CMB depending on which direction you look. If you go 5 billion light years in any direction, things would still look the same, and you would still be in the center of the universe. Nothing in human experience prepares us to think about the topology of space-time. Space is curved in N dimensions, and we are still trying to figure out the shape of that curve and how big a number N is.

Originally Posted by Larry Caldwell

One of the implications of the Big Bang is that the universe is not infinite, it has a radius of about 14 billion light years. That's a really big number, but nothing like infinite. If you want some fun things to think about, realize that the whole universe started inside the Big Bang, and is still there. The Cosmic Microwave Background started out as high energy gamma rays, and has been red shifted because we are moving away from it at nearly the speed of light. Everything in the universe is moving away from the Big Bang at nearly the speed of light, except we are inside it, so "away" has no meaning. Instead, we say that space-time is expanding.

Another really fun thing to think about is that every observer in the universe is smack in the center of the universe. If that were not true, there would be large variations in the CMB depending on which direction you look. If you go 5 billion light years in any direction, things would still look the same, and you would still be in the center of the universe. Nothing in human experience prepares us to think about the topology of space-time. Space is curved in N dimensions, and we are still trying to figure out the shape of that curve and how big a number N is.

This is very wrong. The big bang makes no statement on the size of the universe, it could be finite or infinite, we don't know. Nobody can be "inside the big bang" since the big bang is an event in the past. The CMB is not redshifted because we are moving away from it at nearly the speed of light, it is redshifted because the scale factor has grown between when it was emitted and when we now receive it. Also the curvature of spacetime is intrinsic, meaning our 4d spacetime or 3d space is just that, 4 dimensional or 3 dimensional respectively.

We don't know what happens beyond our observable universe, our investigations into these "larger" questions are guided by the cosmological principle. This is a principle stating that on large enough scales the universe is basically the same everywhere. There is no way to know wether it's correct, it's a principle that turns out quite useful so we use it.

There are other theories about what goes on at the much larger scales than our observable universe, even one saying that it has fractal structure.

Have you read any books written by Michio Kaku? He does a good job with going in depth about different possibilities multiple universes. It could be what you are looking for as far as something other than small scale thinking/mainstream theories.

Originally Posted by XPARATROOP

"Small scale": The visible universe as we can see it today. Again I refer to the river rapids or how about a grain of sand on your LOCAL beach. We just can't seem to grasp infinite. We assume that what we can see is all there is and since it's expanding it must have began the expansion at some point. As the rapids have numerous variables which cause differences in the flow of the same body of water, the infinite universe has similar but endless movements. WE just happen to be in a part which is expanding. When we are able to see further than we do now we MAY discover that.
I am thrilled to have been alive to witness the expansion of the visible universe by Hubble and other means. I hope we (Humans) don't stop any time soon.

Does the big bang need to have been an event? IF the universe is infinite ... then wouldnt the Big Bang just state that in the past we were closer together ... but since we are infinite .... then there is no requirement for a T=0 .... COuldnt you just keep extrapolating backwards in time to a hotter and hotter and more compact universe? Or would they just say that the big bang is when our entire visible universe was all in the same microscopic place.

Originally Posted by caveman1917

This is very wrong. The big bang makes no statement on the size of the universe, it could be finite or infinite, we don't know. Nobody can be "inside the big bang" since the big bang is an event in the past. The CMB is not redshifted because we are moving away from it at nearly the speed of light, it is redshifted because the scale factor has grown between when it was emitted and when we now receive it. Also the curvature of spacetime is intrinsic, meaning our 4d spacetime or 3d space is just that, 4 dimensional or 3 dimensional respectively.