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How large is our universe?
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Who ever narrated this sounds like a combo of Carl Sagan and Stephen Hawking.
 
So Hawking's electrical voice thingy and Sagan sound similar? I guess so
 
combine the 2...maybe its just me
 
And whatever contains it has to bigger..and whatever contains that has to bigger and...so on...
The container > than the contained.
 
Eraj: At least twice as far as we can see, actually. Possibly further (depending on whether the speed of light is constant across time and on how space curves at the edge of the universe)

Riaz: Depending on your definition of "universe" it may or may not be meaningful to talk about something containing a universe. Then, even if it is meaningful to talk about the universe being contained, comparative size may still not be meaningful.
 
On these scales, "largeness" doesn't really have any meaning. Just that we are very small.
 
By seeing i mean with the eyes of our brain.The knowledge of science that we do have now.
 
+Yuchen Gao if there is anyone out there able to watch us, it's likely they will take notice of the several hundred nuclear weapons tests we have done in the past several years. If there is something that will travel through deep space that isn't created from nuclear weapons detonation, it's pretty likely LHC will emit it (probably without knowing it) or we aren't even close to having the technology to create it. On that note, you should turn your lights off, so that we can make the resources on this planet survive long enough so that we can comfortably transition to long range space travel instead of frantically sending a few final survivors into space.
 
vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvvveeery gooddddddddddddd
 
If the universe is expanding, and that expansion is accelerating, then at some point galaxies at the edge of our observable universe will be spreading away from us faster than light and seem to disappear. That is mind bending. I wonder if the 2 micron survey, if repeated in the distant future, can determine if the most distant observable galaxies have crossed that horizon. These galaxies accelerating away should color shift to a lower wavelength of light, then fade to un-observable.
 
I may not have got this right:

The observable edge of the universe is nearly 14billion light years away, but, because this is receeding from us, its current position must be around 46billion light years away. The actual edge will be further away than that (as suggested in this video). I would agree with Charles Hill that the actual edge will be the point at which the expanding matter finally achieves the speed of light. This all seems to contradict the notion that the universe is just 13.75billion years old.

How about this for an idea: When the matter at the edge of the universe achieves the speed of light it becomes energy (e=mc^2). This energy must go somewhere. How about if it is somehow fed back continuously into the sytem to create new matter? This would make the whole system a continuous process with new matter being constantly created within the universe and old matter being converted to energy at the edge. No beginning, no end. Maybe 13.75billion years is just the age of our part of the universe? The rest ranges from 'new' to however old it would have to be to reach light-speed at the edge.
 
+Trevor Melhuish, I am entertaining your theory. If the oldest matter converts to energy when the accelerating universe expansion achieves light speed, the COBE microwave radiation images from the video are not necessarily the echo of the big bang, but actually the output of the continual process of matter dying at the farthest reaches of the universe.

Furthermore, is something at the center of the universe repelling matter (anti-gravity?) to cause this accelerating expansion toward the universe horizon? Where is our galaxy in this continuous process?


Regarding the age of the universe, by Einstein's relativity, time would slow to a crawl (by our measure) within those accelerating galaxies approaching the universe horizon. Do things happen significantly slower in our galactic neighborhood since our matter was formed and began expanding and careening toward the universe horizon in the course of billions of years? If we are accelerating as part of the expansion of the universe, would relative time affect our perception such that the actual age of our galaxy is less than 13.75 billion years?
 
+Trevor Melhuish that's a really interesting idea. I think that the matter would not be radiating energy, because in it's own frame it is not moving at near light speeds, and it is not interacting locally with near-light speed (within the local reference frame) objects, so we would not be seeing higher than normal radiation - which should still look like whatever gave off that radiation in structure, even if it is "red-shifted" as heck.
 
Thanks for your comments +Charles Hill . Maybe the background microwave energy is the mechanism by which the energy in the system is returned towards the centre? What I like about this idea is the way it allows the universe to have always existed and to continue for ever, even if the actual matter is continuously renewed. This seems, to me, rather more plausible than a 'big bang' start at some point.

No doubt there are problems with this idea, but I think it's good to throw around ideas: there maybe something that triggers a new idea that gets us nearer the truth.
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