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Where is the center of the universe?

by JediSouth
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salvestrom
#145
Feb8-12, 09:05 PM
P: 226
Quote Quote by ynot1 View Post
Yes, per Feynman, although the probability of such an event is pretty remote.
"Do they?" was rhetorical sarcasm over your use of the word "allow".
DaveC426913
#146
Feb8-12, 09:20 PM
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Quote Quote by salvestrom View Post
"Do they?" was rhetorical sarcasm over your use of the word "allow".
I would say he has used the word correctly, and agree with his statement.
salvestrom
#147
Feb8-12, 10:12 PM
P: 226
Quote Quote by DaveC426913 View Post
I would say he has used the word correctly, and agree with his statement.
Correct useage or not, I find the use of the word interesting.
rglong
#148
Feb9-12, 11:12 AM
P: 7
I am just putting what my thoughts are
since all finite matter has a center and the universe is finite, that it must have a defined center even if you are on a lake and look around and cant see the shore as a frame of referance, the lake still has a center. Our inablity to find the center does not mean that the center does not exist. If the universe does not have a center then it cannot be finite.
ynot1
#149
Feb9-12, 12:05 PM
P: 90
Quote Quote by rglong View Post
If the universe does not have a center then it cannot be finite.
So where would you find the center of an infinite universe, if such a thing exists? Or did I miss something?
DaveC426913
#150
Feb9-12, 12:19 PM
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Quote Quote by rglong View Post
I am just putting what my thoughts are
since all finite matter has a center and the universe is finite, that it must have a defined center even if you are on a lake and look around and cant see the shore as a frame of referance, the lake still has a center. Our inablity to find the center does not mean that the center does not exist. If the universe does not have a center then it cannot be finite.
This is not at all true.

You are standing on the surface of the Earth - a 2-dimensional plane with a finite area. Where is the centre of the Earth's surface?
SHISHKABOB
#151
Feb9-12, 01:28 PM
P: 614
Quote Quote by DaveC426913 View Post
This is not at all true.

You are standing on the surface of the Earth - a 2-dimensional plane with a finite area. Where is the centre of the Earth's surface?
would it be that there is no center or that every point is the center? Or is there a difference between those two?
rglong
#152
Feb9-12, 01:32 PM
P: 7
The center of the Earth's surface is not the center of the Earth as a whole. A solid 3-d shape like the Universe does have a center. And the center of the Earth's surface could be said to have infinite centers as each point can be reached by going around the Earth, and the path you follow has a midpoint. But as I said, the Earth does have a center. Also, the surface of the Earth can not be made into a 2-d shape, the surface of the Earth is also a sphere and the center of the spheres mass would be at the center of the sphere. If you laid the Earth out flat, then it would have a defined center since you would have to chose a latitude or longitude to define as the edge, no matter where you cut a globe and lay it out, you will end up with a center.
rglong
#153
Feb9-12, 01:36 PM
P: 7
Quote Quote by SHISHKABOB View Post
would it be that there is no center or that every point is the center? Or is there a difference between those two?
If you view it at a single point, the center would be the opposite pole to you. If you did it for every point on a sphere, there would be infinite centers on the sphere.
rglong
#154
Feb9-12, 01:38 PM
P: 7
Quote Quote by ynot1 View Post
So where would you find the center of an infinite universe, if such a thing exists? Or did I miss something?
This is presuming that the universe is finite. If it were infinite, then there would be no center.
Tanelorn
#155
Feb9-12, 09:53 PM
P: 711
If the Universe is not truely infinite would this suggest that there is something else besides the Universe?
I dont mean the observable universe here, I mean the whole Universe which is a continuum of our own observable Universe.
By something else I mean more Universes separate to our own or perhaps something in which our Universe is contained in some way.
DaveC426913
#156
Feb9-12, 10:07 PM
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Quote Quote by SHISHKABOB View Post
would it be that there is no center or that every point is the center? Or is there a difference between those two?
The centre point of a surface is a special, privileged point that no other point on the surface has. There is no point on the surface of a sphere that is privileged, therefore, no point is the centre.

Quote Quote by rglong View Post
The center of the Earth's surface is not the center of the Earth as a whole.
Do you grant that the surface of the Earth is finite in extent, yet has no centre?

Quote Quote by rglong View Post
A solid 3-d shape like the Universe does have a center.
What makes you say that?

Some 3D shapes have centres. That does not mean all do.

Quote Quote by rglong View Post
And the center of the Earth's surface could be said to have infinite centers
Then none are unique. Thus, they cannot be centre.

Quote Quote by rglong View Post
If you laid the Earth out flat, then it would have a defined center since you would have to chose a latitude or longitude to define as the edge, no matter where you cut a globe and lay it out, you will end up with a center.
That is correct. The moment you artificially divide it up, providing artificial boundaries, you make artificially privileged points. You would no longer have a surface of a sphere.

If you go nuts with your scissors and cut the Earth's flattened shape into confetti, then your shape will have straight edges and acute vertexes. Does that say anything at all about the original shape of the Earth's surface before you mangled it? Does it mean "the surface of the Earth has straight edges and vertices"?
DaveC426913
#157
Feb9-12, 10:16 PM
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Quote Quote by Tanelorn View Post
If the Universe is not truely infinite would this suggest that there is something else besides the Universe?
It does not suggest it, no.

Nor does it in-and-of-itself rule out there being something else - but not being infinite does not suggest there is anything else.
Tanelorn
#158
Feb9-12, 10:22 PM
P: 711
Well it is hard to imagine that everything that is or ever can be is finite. There again it is difficult to imagine infinite as well.
It is also hard to imagine that there is any final level of reality or structure, since everything we know of in our everyday life is contained inside or is a part of something else; sub atomic particles, atoms, molecules, planets, solar systems, galaxies, clusters etc.
DaveC426913
#159
Feb9-12, 10:25 PM
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Quote Quote by Tanelorn View Post
Well it is hard to imagine that everything that is or ever can be is finite. There again it is difficult to imagine infinite as well.
We don't have to imagine it. Imagination is flawed by definition, since it depends on things we've experienced before.

The mathematics shows us. It is the only accurate model.
salvestrom
#160
Feb9-12, 11:00 PM
P: 226
Quote Quote by DaveC426913 View Post
We don't have to imagine it. Imagination is flawed by definition, since it depends on things we've experienced before.

The mathematics shows us. It is the only accurate model.
What a bizarre thing to say. I'm pretty sure I've never experienced a thousand mauruading snargle-bangs from Ceti-Prime Zeta demanding my left shoe and some yo-yos. (I may have experienced Douglas Adams at some point).

And an infinite universe is not the only model, you say this yourself. It's also possible that the universe is finite and unbounded. It's also possible there is an outside to what we currently consider the universe, regardless of whether the model requires it.

The moment you consider anything you cannot currently see, you are imagining.
Chronos
#161
Feb9-12, 11:53 PM
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There is nothing imaginary about the math. Get used to it.
salvestrom
#162
Feb10-12, 12:38 AM
P: 226
Quote Quote by Chronos View Post
There is nothing imaginary about the math. Get used to it.
Imaginary numbers? Virtual particles? Besides, imagination and imaginary are not the same thing.


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