Seems a bit pointless to me ?
But what do I know ?
But what do I know ?
Why is the Universe so big ?
You have to figure the universe has been expanding since the start of the universe and it has not hit a "wall" yet.
Expanding at the speed of light for a very long time the Universe is a big place but in the same sentence you have to say that the Universe is full of a lot of nothing. You can travel in space for a long time and not bump into anything.
Expanding at the speed of light for a very long time the Universe is a big place but in the same sentence you have to say that the Universe is full of a lot of nothing. You can travel in space for a long time and not bump into anything.
| jguritza wrote: |
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Expanding at the speed of light |
Even faster, actually.
Yes it's a big place and we don't even really know how big just yet. We can guess. Bigger than most of us can ever really imagine I guess.
| ocalhoun wrote: |
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Even faster, actually. |
Currently scientists believe that the universe is expanding at very close to the speed of light but not past it. Our modern knowledge of quantum physics does not allow anything to travel faster then light.
| Cmink32 wrote: | ||
Currently scientists believe that the universe is expanding at very close to the speed of light but not past it. Our modern knowledge of quantum physics does not allow anything to travel faster then light. |
Expansion does not cause anything to travel faster than light, even though 2 points may be receding from each other at superluminal velocity. It is the space between them that is expanding and that can cause 2 very distant objects to recede faster than light.
Inflation in the early moments of the universe (10^-35 - 10^-33 seconds after the Big Bang) caused a faster-than-light expansion that explains the homogeneity of the visible universe.
This article puts the size of the universe at 156 billion light years.
| Cmink32 wrote: | ||
Currently scientists believe that the universe is expanding at very close to the speed of light but not past it. Our modern knowledge of quantum physics does not allow anything to travel faster then light. |
It is Special Relativity that limits velocity to c (way before QM). Spacetime is not so limited (as Doc says) and in fact we routinely observe galaxies with redshift > 1.7 which means that at the time the light set-out the galaxy was 'receding' from us at >c
It's difficult to explain. 
That some creatures like germs is so small can't be explained very well, either.
That some creatures like germs is so small can't be explained very well, either.| Quote: |
| Why is the Universe so big? |
Probably because relative to the Universe the earth is so small. When it gets to me, I probably am less than an atom in relation? Perhaps Chris can put it in much better scientific language.
It is almost like being in a room full of other people, and the ceiling is not tall, and you feel a good size, and then going out in nature and looking up at very high mountains, and feeling so infinitessimally tiny and insignificant. Looking up at the sky, well that is about my limit. My mind can't visualize how big the Universe is.
Well, the first point is that words like 'big' and 'small' are not very useful in science. They only really mean something when you have the words 'in comparison to...' added. Because our language naturally reflects ourselves, the we normally use the words 'big' and 'small' in comparison to ourselves. Thus a tall person is big, a boulder is big, a skyscraper is really big...and so on.
Once you get much above the size of a building then 'big' really doesn't cut it.
You can get some sort of impression of the size of the earth in relation to the universe from a couple of apps on the web
http://www.pbs.org/wgbh/nova/universe/tour_map05.html
http://www.atlasoftheuniverse.com/12lys.html
Now, if we ditch the word 'big' (it really has no meaning in this context) then we could rephrase the question as - why are there so many stars and galaxies in the universe? That is a deep question in physics and we could devote the whole board to discussing it and still only scratch the surface.
Once you get much above the size of a building then 'big' really doesn't cut it.
You can get some sort of impression of the size of the earth in relation to the universe from a couple of apps on the web
http://www.pbs.org/wgbh/nova/universe/tour_map05.html
http://www.atlasoftheuniverse.com/12lys.html
Now, if we ditch the word 'big' (it really has no meaning in this context) then we could rephrase the question as - why are there so many stars and galaxies in the universe? That is a deep question in physics and we could devote the whole board to discussing it and still only scratch the surface.
th universe is so big because the expansion was happened and the inflation helped the expansion 
in 2000 scientist found our universe is expanding forever (so the universe is getting even bigger and bigger)
in 2000 scientist found our universe is expanding forever (so the universe is getting even bigger and bigger)
| luxgud wrote: |
| Seems a bit pointless to me ?
But what do I know ? |
there is a god and he created the universe so big because if he mess up on earth he can switch to a new planet and start all over.
galactic isolation is necessary otherwise one dominant allien can destroy the others even we humans may be food for alliens. So the greatest programmer designed a very biig universe.
It keeps on expanding due to sum energy..dark energy as far as I recollect!... 
Universe is neither big nor small, surely ?
| nanunath wrote: |
| It keeps on expanding due to sum energy..dark energy as far as I recollect!... |
No, Dark will halt the expansion some day.
| RanVijay wrote: | ||
No, Dark will halt the expansion some day. |
Dark? What?
| RanVijay wrote: | ||
No, Dark will halt the expansion some day. |
Halt? How?
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