ChatterBank0 min ago
What is beyond the universe?
I watched the Big Bang programme on Panorama last night. I've never bought into the Big Bang Theory so it's nice to see that it is losing momentum among some scientists. Obviously no one can answer my question with any certainty so just your thoughts and theories are welcome. Basically what I am wondering is, if the universe is expanding, what is it expanding into? Is the universe creating time and space at its outer reaches as it expands?
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For more on marking an answer as the "Best Answer", please visit our FAQ.Matter, space and time are inter-related. If there is no matter there is no space, no space no time. So there is nothing that we would recognise outside of the universe of matter. That is not to say that there is nothing. Space could be an immense energy field and matter just ripples upon it, we will probably never know for sure.
I missed the program but I don't think the Big Bang is losing any momentum with anybody mainstream - the evidence for it is way too strong.
the point often misunderstood is that time is bound up with space so although if you extrapolate back the expanion of the Universe back you get to the "Big Bang" if you were in the Universe running the clock back time would go slower and slower until it stopped at that point - so the Universe in a very real way has always been here.
Issues with time are very hard to get to grips with.
As for what the Universe is expanding into try this as an exercise
You are a two dimensional triangle living on the surface of a hot air baloon. You are a small triangle so the baloon looks nice and flat to you.
But the baloon continues to inflate - your Universe gets larger and larger and you can't work out where all this extra space keeps coming from.
This is similar to one idea that the Universe may be a 4D torus ( ring doughnut ) shape.
This would mean that if you could go far enough in any direction you'd come back to the same point.
here's a video of a 4D torus
the point often misunderstood is that time is bound up with space so although if you extrapolate back the expanion of the Universe back you get to the "Big Bang" if you were in the Universe running the clock back time would go slower and slower until it stopped at that point - so the Universe in a very real way has always been here.
Issues with time are very hard to get to grips with.
As for what the Universe is expanding into try this as an exercise
You are a two dimensional triangle living on the surface of a hot air baloon. You are a small triangle so the baloon looks nice and flat to you.
But the baloon continues to inflate - your Universe gets larger and larger and you can't work out where all this extra space keeps coming from.
This is similar to one idea that the Universe may be a 4D torus ( ring doughnut ) shape.
This would mean that if you could go far enough in any direction you'd come back to the same point.
here's a video of a 4D torus
Well I watched the Horizon version that happenned to be on last night too!
When refering to the big bang words like "before" and "expanding into" have no meaning you have to throw away everything you know about our little 3 or 4d world and black box the the unimaginable, then you can study what is left. So we accept that the big bang happenned and start our studies a few nano seconds after. We have no way of explaining what was there "before" because all our space and time was created at that instant. The univers is not expanding into anything because nothing is there, again black box that, then you can staudy a notional "edge".
When refering to the big bang words like "before" and "expanding into" have no meaning you have to throw away everything you know about our little 3 or 4d world and black box the the unimaginable, then you can study what is left. So we accept that the big bang happenned and start our studies a few nano seconds after. We have no way of explaining what was there "before" because all our space and time was created at that instant. The univers is not expanding into anything because nothing is there, again black box that, then you can staudy a notional "edge".
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I think we may be getting a bit off course with the whole Torus idea. The torus is the shape for a 2d universe, defining a shape for 3d universe is one of the great problems of physicas currently. Remember the old asteroids game? You went off the bottom and came on the top so you could be going round a cylinder but similarly you went off right and came back on left so that cylinder was bent rount and joined, ie a torus. Jake care to comment here have I misunderstood your 4D torus idea earlier?
"presumably scientists"?
presumably they may want to go back and revisit their relativity in that case
When we are dealing with higher dimensions we contort the representations to fit into the dimensions that we have.
That animation of a 4 torus is of one seen from the outside.
If we go back to the flat-land analogy - the triangle hears a voice and says "who's there"
the doughnut says "sorry you can't see me I'm above you"
What's "above" says the triangle
"never mind" says the doughnut and starts to move throught the fabric of the balloon (never mind how)
the changing form of the 4D doughnut moving though our 3D world is what that animation is.
However in terms of the Universe we would be actually in the 4D torus the term outside doesn't have any meaning (if there are 4 dimensions only).
At some stage you reach the maximum number of dimensions and the term outside has no meaning in the same way that you reach the begining of time and the word before has no meaning.
You may not like the idea but we all develop our intuitions in a tiny world with average temperatures in average gravities and average speeds.
Then we try to apply those intuitions to the birth of the universe - then we get surprised when it doesn't seem to make sense
Does it make sense to you that electrons can be in two different places at the same time?
presumably they may want to go back and revisit their relativity in that case
When we are dealing with higher dimensions we contort the representations to fit into the dimensions that we have.
That animation of a 4 torus is of one seen from the outside.
If we go back to the flat-land analogy - the triangle hears a voice and says "who's there"
the doughnut says "sorry you can't see me I'm above you"
What's "above" says the triangle
"never mind" says the doughnut and starts to move throught the fabric of the balloon (never mind how)
the changing form of the 4D doughnut moving though our 3D world is what that animation is.
However in terms of the Universe we would be actually in the 4D torus the term outside doesn't have any meaning (if there are 4 dimensions only).
At some stage you reach the maximum number of dimensions and the term outside has no meaning in the same way that you reach the begining of time and the word before has no meaning.
You may not like the idea but we all develop our intuitions in a tiny world with average temperatures in average gravities and average speeds.
Then we try to apply those intuitions to the birth of the universe - then we get surprised when it doesn't seem to make sense
Does it make sense to you that electrons can be in two different places at the same time?
The programme centred on members of the faculty of the Perimeter Institute for Theoretical Physics...
http://www.perimeteri....ca/index.php?lang=en
...alongside contributions by others such as Sir Roger Penrose...
http://en.wikipedia.org/wiki/Roger_Penrose
...and Michio Kaku...
http://en.wikipedia.org/wiki/Michio_Kaku
http://www.perimeteri....ca/index.php?lang=en
...alongside contributions by others such as Sir Roger Penrose...
http://en.wikipedia.org/wiki/Roger_Penrose
...and Michio Kaku...
http://en.wikipedia.org/wiki/Michio_Kaku