1. If all galaxies are moving, (mostly away it seems) isn't there a way to plot a point of origin for some of the galaxies by drawing a line from where they are now to where they were in the past? Would the focal point of this plot be the center or origin point of the universe?

2.

3. First, welcome to the forum. Second, we have discussed this here already uncountable times. No, this is not possible. It is not the galaxies that move away from each other, it is the space that expands and drags everything along with it. It is just as impossible as it would be to locate the centre of an inflating balloon by tracing back the paths of dots painted on its surface.

4. Unless the baloon is a long and skinny one, most round baloons have center don't they? Is it not possible to locate the center of sphere? Also, how do I find these previous discussions on this topic?

5. Originally Posted by diablobo
Unless the baloon is a long and skinny one, most round baloons have center don't they? Is it not possible to locate the center of sphere? Also, how do I find these previous discussions on this topic?
The idea is that the surface of a balloon is a 2D representation of the 3D universe. What you are proposing is that there must also be an edge, if you want to postulate a centre. But this can already be excluded by relatively simple arguments. One of the strongest is that such a universe would be unstable and not isotropic which contradicts all observations. The universe is already everything by definition. The expansion cannot be described and understood as something expanding into something like an empty space. It is the expansion of space itself in a sense that all distances - if undisturbed by local perturbations like gravity - constantly increase at the same rate everywhere (the global rate, however, can change in time).

Examples of previous posts (there is a search function at the top of the page):
http://www.thescienceforum.com/viewtopic.php?t=24972
http://www.thescienceforum.com/viewtopic.php?t=24373
http://www.thescienceforum.com/viewtopic.php?t=24671

All the best!
Dishmaster

6. As dishmaster said.

Allthough, there can be a rest speed to which all speeds compare relativily.

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