Lydiot wrote:MIG29pilot wrote:I know what you are going to say; We aren't. I answer: There are two theories about the shape of the universe: One says it is a three dimensional space, with a definite center; think of the inside of a balloon. The other says that the universe is like the surface of that balloon, or the surface of the earth; definite distance and size, but no center.
BOTH are only theories.
The word "theory" should be used with caution.
"A scientific theory is a well-substantiated explanation of some aspect of the natural world that is acquired through the scientific method and repeatedly tested and confirmed through observation and experimentation."
I doubt that's what you mean when you use the word. If that's what you mean then you also invalidate our understanding of electromagnetism, because it too is "just a theory".
However solid a theory may be, they are not fact. They, while seeming perfectly true today, may seem absurd tomorrow. Medieval doctors could have given you a whole book on the Doctrine of Humours. We now know better. Never mistake a theory for a fact.
MIG29pilot wrote:The first has the evidence of daily experience, of the fact that we know that it is clear to see that the universe is three-dimensional space in its favour.
The other has the word of a handful of persons who don't want to be in the centre of the universe.
Actually, I don't think you're right for a couple of reasons (and I'm thereby not saying the universe is "three dimensional").
First of all, we can't trust our "daily experience", because to a lot of people the earth looks flat, and it looks as if the sun revolves around the earth. Surely you claim neither is true, right? We've evolved to perceive four dimensions to the extent they're useful to our species. A very very small creature, to the extent it can perceive dimensions, probably perceives only two. That's because it can get traction and climb almost any surface in any direction. Thinks spider but far smaller. To it there's no meaningful distinction between two and three dimensions. As the surface "turns" it just follows along on it. No worries about falling or anything. But a cat for example has to worry about three dimensions. If they're at the edge of a cliff they have to be careful because they can hurt themselves falling down. So once they're beyond a certain height it's a problem. But they probably don't care about whether the height is a mountain or a hill with a steep cliff. We on the other hand do care. That's because when we migrate, and we do, we have problems with crossing mountains as opposed to hills. If we're looking for fertile soil it's an issue. In addition to that we care about time because we can use that to our advantage when farming. So while a cat probably doesn't care or even is aware of seasons, we do.
The only reason the spider thinks life is two dimensional is he can't see very far. Same with people; our view is obstructed by terrain and our naturally low position. Go to see and you are able to see the curve. Go to space and you will see how it is a sphere. And wherever you are looking, whatever you see, the earth is still a sphere--unless you say that it changes shape depending on where you are.Whether we don't care about things does not mean they don't exist, if that's what your trying to say. I don't vanish when you finish reading my post. At least, I hope notSo once they're beyond a certain height it's a problem. But they probably don't care about whether the height is a mountain or a hill with a steep cliff. We on the other hand do care. That's because when we migrate, and we do, we have problems with crossing mountains as opposed to hills. If we're looking for fertile soil it's an issue. In addition to that we care about time because we can use that to our advantage when farming. So while a cat probably doesn't care or even is aware of seasons, we do.
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Our "daily experience" is absolutely no good basis for making statements about these sorts of things. If it was then you wouldn't be making the statements you are to me right now, because we would never have found the electron or understood electricity and formulated an accurate theory of electromagnetism (needed for computers).
Secondly, even if space is three dimensional it doesn't mean what you think it does if the universe is expanding. If the universe is three dimensional and expanding, consider being in one of the "points" in the following image:
As that "cube" or "universe" expands ALL "points" move away from each other. Since that's the case, the "experience" on ANY of those "points" will be ALL other points moving away from it. In other words, in a three dimensional expanding universe it will look like you're in the center regardless of where you actually are.
Let me remind you that it was "daily experience" which led Maxwell to all this stuff; that all discoveries are "daily experience" because they are part of a working universe, our universe.
As for that pic, it doesn't matter what dotty sees, he's not in the middle. If he was loking from a better viewpoint he would see that. That shape has a definite, calculable point which is the center.