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I'm looking at the bright side, it means that we don't even need to achieve speed of light to travel to other galaxies, because the universe is ever-expanding it means that some planets will occupy the space our planet is in now, so theoretically if we can figure how to live in a static point in the universe (e.g, absolute position, not relative to our solar system) some day in the future (millions of years from now) we could visit other galaxies.


As maaku stated there is no static point in the universe.

This is core point of relativity. There is no absolute coordinate system whatsoever. Everything is defined as in relation to something else.


what? No. there is absolutely no such thing as an absolute position in the universe.


What if we find the point where the Big Bang happened?


What if we find the point where the Big Bang happened?

You're already there. Since all of space expanded from one point, by definition the Big Bang actually happened right here (and also over there) [1].

[1] http://en.wikipedia.org/wiki/Brouwer_fixed-point_theorem


There is no such point (or it is everywhere if you like, as someone else had said).

The best analogy I've seen is that of ants on a balloon. They live in what appears to them to be a two dimensional universe. As you inflate the balloon, they observe their own universe getting bigger. But the "point where the Big Bang happened" to them is not a point that even exists in their universe any more. They cannot get back there, since the higher third dimension does not exist in their universe.


That's a nice analogy. Now I understand!


That's exactly where you are right now (and everywhere else).


This illustrates the confusion that occurs when people are exposed to horrible "artistic renderings" of the Big Bang as a huge explosion that throws matter all over the place.

It's better to think of the Big Bang as an unimaginably intense period of expansion and cooling of whatever substance the earliest universe was made out of (see Inflation theory). It was not an explosion that happened in a pre-existing spacetime.




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