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Old 10-11-2008, 08:14 AM
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sjastro
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Quote:
Originally Posted by xelasnave View Post
Steven I thought Space time is a geometric way of describing space so I am confused.
If space time is of four dimensions are not three of them spatical... at least three of the four relate to dimensions that will give us definition of volume...
I am not sure if I get the space time thing.. as I understand it is geometry (simple or complex nevertheless geometry) and that this geometry deals with what could only be described as spatical quantification of space.

Anywyas you have given me something to entertain me all night.. I will think about this more...

Whilst doing nothing today I stacked 1 hour 10 minutes of wide field shots and even with no photo shop I must say ...man is it something...cant down size it or I would post it to show at least I did something today.

alex
Alex,

Think of space-time as a grid which determines the position (and time) of galaxies in the Universe. If a galaxy moves within space or space expands the position of the galaxy changes on the grid.

Suppose the scale of the grid is allowed to expand. Each galaxy will appear to move away from every other galaxy but their position on the grid remains the same. (This doesn't apply to gravitationally bound galaxies.)

Hence space-time expands but space doesn't. It helps explain why every observer in the Universe is the origin and why the recession velocity of a distant galaxy is proportional to the distance to the observer.

On a different subject, doesn't the software that came with your camera allow you resize images?

Regards

Steven
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