What happens to light over time?  If light stays light the universe should be a bright place but it looks dark
341014
You are right!  If the universe were infinitely old, the universe would be very bright.  However, early after the big bang, there was a period called "inflation", during which the early universe expanded much faster than the speed of light-because of this, the majority of object were seperated prior to the universe becomine transparent (when the concentration of hydrogen dropped low enough that light could travel long distances).  Now, the far distant places are traveling away at nearly the speed of light, and there are large dark places which absorb light.
5022
This is the same as the speed of light.  Dark is simply the relative absence of light.  The sun could stop shining and we would not know for like eight minutes.  (Not that the sun would just stop shining, but use your imagination.)
115426
Yes, yes, yes, yes..!!! Scientists have stopped light.\n\nThe details of when, where and how are here ---\nhttp://science.nasa.gov/headlines/y2002/27Mar_stoplight.htm\n\nhttp://physicsweb.org/articles/world/14/9/8
995661
no.  it changes over millions of years as the universe changes and our relationship to the sun changes, but i'd guess it was pretty close as to what is now.
31705
The best guess today: no.\n\nIn modern cosmology the topology of the universe appears to be open. "Topology" meaning the shape, although in the case of the universe to observe the shape we would have to exist in 4 spatial dimensions. Since we're stuck in 3-dimensions we have to get by on analogies.\n\nThe topology or shape of the universe is something which comes out of Einstein's General Theory of Relativity. It depends primarily on the distribution of mass and energy in the universe. If the amount of mass-energy is more than a certain critical value then the universe would be "closed." Basically the mass would curve space-time back onto itself. In a closed universe you could fly off in the direction of the north pole and (after about 25 billion years) and circle the universe to land on the south pole.\n\nIf the amount of mass in the universe is less than this critical value then the topology of the universe is a bit more complex, but, to answer your question space would be infinite.\n\nBased on what we know today that is the case, space is infinite.\n\nHowever, we cannot see an infinite universe. When we see things that are farther away we also see them from deeped in the past. A galaxy we see that is 10 billion light years distant is actually a view of what the galaxy looked like 10 billion years in the past.\n\nWhen we look farther in space, and thus earlier in the history of the universe, we eventually run into the microwave background. For the first 10,000 years or so after the Big Bang the universe was so dense that it wasn't yet transparent. When the density dropped enough to be transparent then some of the light could escape for us to detect much later.\n\nHowever, while the universe is thought to be about 13 billion years old, we can actually see out a bit farther than that, I think around 20 billion light years, because the universe is expanding.\n\nWhat this boils down to is that there is a sort of "wall" beyond which we can't see. This wall corresponds to a time soon after the Big Bang. However, studies of the total mass-energy within the universe strongly suggest that it has an open topology - that it is infinite.\n\n(Of course it is possible that this infinity will be refined when we have a better theory of how Quantum Mechanics and General Relativity play togther. String Theory is one way to combine these two.)
242351
Even if the universe does curve around, maybe you'll see the side of your head.  I'm not sure how distorted it would look either.  Like a previous poster said, you'd have to wait until the light made full circle so you'd be dead by then.  You'll have to leave a passdown for the next shift.
809960
Actually, at our close range to the sun, it would be so bright that everything would be completely washed out. It would be blinding to even be outside. It is true that the photosphere will be cooler, but the sun will be so much larger that the total light we receive will be much, much more. As for sunset and sunrise, if I had to guess I'd say that they would take longer and it would stay bright for a long time after the sun goes down (and get brighter a long time before the sun comes up). This is all assuming that it hasn't swallowed the Earth yet, which it will do at some point.
373426
Well, since, as stated before, darkness is the absence of light, it travels at the exact speed of light in a given medium. For example, if you turn a light on in a darkened room, it gets bright very quickly (exactly how quickly will depend on the type of light bulb or the colour of the light you use), but when you turn it off, it gets dark at the same rate. Though darkness isn't something that really "travels", what you're measuring is how fast light dissipates, which is at the speed of light!
643948
There is a line of reasoning that would suggest that the chances are quite high.  Here is how it works.  We start by assuming that the universe if infinite.  Now - since the universe is not infinitely old  (it started at the big bang)  you can think of the universe as being partitioned into three dimensional bubbles called "universe horizons" - this is a bubble with a radius equal to the distance that light would have travelled since the big bang - about 13 to 20 billion light years.  The significance of this bubble is that there is no way for light or matter from outside this bubble to reach you since the universe isn't old enough.  But, since the universe is infinite, there will be an infinite number of these universal bubbles.  Now - mathematically - there can only be so many possible ways of arranging sub-atomic particles inside a given bubble - any given point in space will either have a particle there or be empty - if it does have a particle, there are only a finite number of possible particles - therefore there can only be a finite number of possible configuations of matter / energy inside a bubble.  Since the number of possible configurations is finite, but the number of bubbles is infinite, then by necessity the configurations must repeat themselves an infinite number of times - therefore there should be an infinite number of replications of the known universe.  If you can't accept this - then the universe must be finite.
1132849
Infinite -  Darkness is the absence of light, so once a photon has moved past a space the space is filled with darkness immediately
21584
Only matter can reflect light, so outerspace isn't really dark, it's just an absence of matter. Dark matter, on the other hand, is actually dark. It's so dark, in fact, that it is impossible to see with the backdrop of space.\nKeep in mind, though, that the sky is blue not because air molecules are blue, but because of a refraction of light.\nEverything has to do with light...
1124878
It is all throughout space if it exists.  You can't see it because...well...it is dark ;0)
1088204
it depends on the fine partcles of water through which the light rays pass.if the condition is simulated it can remain for quite some time.
574337
There are various conflicting theories about this.Some say universe will keep on expanding.Some say it will be a see saw .Some say it will all end in a big contraction.It's still a open question.
897624
The universe is driven by entropy. Its energy on the whole stays the same, but that energy started off in a small number of very hot things and over time is being redistributed to a much larger number of cooler things. \n\nOne possible fate of the universe is that this will continue indefinitely until every particle in the universe has about the same energy. Nothing else would then ever happen in the universe. The temperature of such a universe would be everywhere very, very cold (below 4K).
345361
The Big Bang theory offers a resolution of your question (also known as Olbers's Paradox). In a universe with a beginning we can receive light only from that part of the universe close enough so that light has had time to travel from there to here since the Big Bang (about 10 billion years ago). So, even if space extends infinitely far, only a limited region, and a limited number of stars, are visible to us. And the accumulated light from this limited number of stars is not sufficient to spoil the darkness of the night sky.\n\nGod is spelled B-I-G B-A-N-G\nPBrax@netscape.com
328994
Dark does not push light away, the light is what is moving. Using your example of "over the horizon", the sun (which produces light) moves to the other side of the earth (where we can't see it) then we see dark. But dark does not move, it is just the term we have come up with for what it looks like when there is no light present.