This is Olbers' Paradox. |
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There's always been an argument that has irritated me about why the universe cannot be infinite. It goes like this: |
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Last edited by Xei; 03-06-2008 at 12:29 AM.
This is Olbers' Paradox. |
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That argument that you hate is incredibly dumb. Two thoughts come to my mind. The first is, an infinite number of stars would not equal a white sky because not all of the stars' light may have reached us yet. Secondly, I don't see why an infinite universe implies that there's an infinite number of stars. It could be a finite cluster for all anyone knows. |
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Usually, an "infinite universe" refers to our space-time continuum not having any physical boundaries. Basically, you could point a ship in one direction and go on forever without ever reaching the "edge" of the universe. It doesn't emply that there is an infinite amount of matter in the universe, which is technically impossible, since all empty space would be occupied by matter. |
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No that's not true. If the universe is infinitely large and only a certain fraction of space is occupied by matter, then there is still infinite matter, as any positive number, be it fraction or not, multiplied by infinity, is infinity. |
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The paradox assumes an infinite universe with randomly dispersed stars. In a universe like this, there would be a certain non-zero probability of a star occupying any particlar point along a line of sight. With an infinite amount of points along any line of sight, the probability would amount to one. |
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But in the case of our universe, there is a finite distance to how far matter has spread since the Big Bang (the observable universe). So the space that matter holds is a known constant, rather than a fraction of infinity (if the space-time continuum is infinite). Since it's physically impossible for matter to have gone further than a certain point, you end up with infinite mass in a fixed volume, thus zero free volume (by the way, how can you fill up all empty space with round particles ?). |
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There are stars passed where the human eye can see. Astronomers have also seen passed the limit of where their are stars. So there isn't an infinite number of stars which reinforces the big bang "theory" and there is not an infinite amount of stars. |
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Once upon a time a disciple went to his guru and asked him, 'Guru, what is life?' To which the guru replies, after much thinking, 'My Son, life is like a fountain.' The disciple is outraged. 'Is that the best you can do? Is that what you call wisdom?' 'All right,' says the guru; 'don't get excited. So maybe it's not like a fountain.'
LDs of 2008: 50, WILD: 3
LDs of 2009: 1, WILD: 0 (resolution: 100 LDs)
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Actually, the theory is that the universe is growing. But the thing is, light is not instantaneous. But if you follow that theory, then eventually, in n years, the night sky would be white. But light also doesn't travel in a straight line (as a whole). It spreads out, getting dimmer. Most of the stars in the distance, by the time they get here, will have spread out, being dimmer. It then goes up exponentially from there. Just like the "1 + 1/2 + 1/4 + 1/8 + 1/16" thing. |
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Last edited by Venomblood; 03-09-2008 at 03:23 AM.
Once upon a time a disciple went to his guru and asked him, 'Guru, what is life?' To which the guru replies, after much thinking, 'My Son, life is like a fountain.' The disciple is outraged. 'Is that the best you can do? Is that what you call wisdom?' 'All right,' says the guru; 'don't get excited. So maybe it's not like a fountain.'
LDs of 2008: 50, WILD: 3
LDs of 2009: 1, WILD: 0 (resolution: 100 LDs)
Art
The ability to happily respond to any adversity is the divine.
Dream Journal Shaman Apprentice Chronicles
Well according to relativity, we are not 'woven' into the fabric, we sit on top of it and it stretches beneath us. This is why when calculated, it appears as though we are in fact at the center of the universe, since everything seems to be expanding and moving away from us. The explanation for this is that no matter is actually moving outward from a center point, the space between is simply expanding. |
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Art
The ability to happily respond to any adversity is the divine.
Dream Journal Shaman Apprentice Chronicles
Cool. |
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So you're suggesting Spacetime could be a hypershpere? |
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The shape of the universe is still a subject of debate. |
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