Olbar suggested that the night sky is dark because the universe was finite in its existance. He deduced that, if the universe was inifinitely old, then in every direction in which you looked, you eye would fall upon a star. One of the 'best answers' to this question when it was last asked, addressed an expanding universe, not an infinitely old universe. If we look at Olbars Paradox in an inifinely old universe, the the question becomes, since we know that stars have a finite life time, could all stars in that infinely old universe that are older than a certain life (say older than 100,000 year) have simply burned out and is, therefore, no longer emitting light, making it impossible to see them? Here we can have an infiniteyl old universe and still retain our 'dark sky' at night.
2006-08-29 18:46:02 · 8 answers · asked by Reggie 2 in Science & Mathematics ➔ Physics
Physicsdude: I most certainly agree with you that our universe appears to be infinite, but if we consider 'infinite' then what we are saying is that the universe is time itself and it would, therefore, be no place, in regards to the extent of the universe, that it, the universe would not be. We human being have a mind that is finite, in the capacity of its purpose, and we, therefore cannot comprehend the infinite.
2006-08-29 19:19:24 · update #1
DrM: Energy density, as you mentioned, is a very significant factor in our experiencing that energy, but if we compare a universe that is ten minutes old to one that is infiintetly old, or even 100 billion years old, there is a very high probability that the latter will have more stars and galaxies, due to the way stars are born in galaxies, and how that birth is dependant on others stars in that galaxie.
2006-08-29 19:24:55 · update #2
That's one possible explanation. If the Universe extends forever and it's static, then the whole sky would be a bath of light because in every direction there'd be a star. The explanation which is most generally-accepted today is that, since there's some convincing evidence that the Universe is expanding, and we know roughly the magnitude of Hubble's constant; for every megaparsec a galaxy is from us, it recedes from us at 75 km/sec, then galaxies further away than about 14 billion light years must be receding from us so fast that their light will never reach us. I've never discovered anything. All I know about astronomy and physics was spoon-fed to me at university in an undergraduate course. But in my humble opinion, some stars are much longer-lived than 100 000 years. Red dwarfs can live as long as 100 000 000 000 000 years,so if our accepted wisdom is correct, as I believe it is. some will last longer than the Universe has been around. In your opinion, where do the new H atoms for the fuel for new stars in this infinitely old Universe come from?
2006-08-29 20:26:24 · answer #1 · answered by zee_prime 6 · 0⤊ 0⤋
Olber's assumption here seems to be that an "infinitely old" Universe is also "infinite" in extent. That's why he thought that everywhere you look, you would see a star covering a point in the sky, thus making the sky look bright.
But I think we can assume that the Universe is "infinitely old" but "finite", then the Universe could still look dark because, as you suggested, the number of visible stars may also be finite (and may even be decreasing) becasue some have died out, and there are no new stars to replace them.
2006-08-30 01:54:22 · answer #2 · answered by PhysicsDude 7 · 0⤊ 0⤋
It is not age of universe or the finite universe that causes the dark sky with few stars. It is the density. There is not enought starts to fill the space. The stars have finite life. So we will always see the holes in the sky
2006-08-30 01:51:30 · answer #3 · answered by Dr M 5 · 0⤊ 0⤋
No. Neither by Biblical accounts, NOR by scientific.
HUBBLE said that we have an expanding universe, which has been PROVEN.
In The Holy Bible of Christians, Jesus says," I go to prepare a place for you." MAYBE meaning, that the stars were intended to be our MANSIONS in the universe!
2006-09-06 23:51:22 · answer #4 · answered by thewordofgodisjesus 5 · 0⤊ 0⤋
An finite universe... perhaps. Or maybe it's just so vast we cannot grasp how much is out there. Our finite could be someone elses walk across the street.
2006-08-30 02:42:06 · answer #5 · answered by Anonymous · 0⤊ 0⤋
Scan the latest about "Black holes". This may cover some of what you are pondering.
2006-09-07 00:14:01 · answer #6 · answered by Weatherman 2 · 0⤊ 0⤋
No, it suggests there are no stars.
The light from stars out further, has not reached us yet.
2006-09-03 13:01:13 · answer #7 · answered by Anonymous · 0⤊ 0⤋
That's pretty much it.
2006-08-30 01:51:39 · answer #8 · answered by Anonymous · 0⤊ 0⤋