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Originally Posted by dipayankar  Well an ellipse has two centres, but since we do not know the shape of the Universe it is difficult to define its center. |
[size=2]An ellipse has two focal points, but these are not called the centre. Commonly, the centre of an ellipse is the point midway between the two focal points. The reason it is difficult to find the centre of the universe is that there isn't one. It disobeys the cosmological principle to say that there exists a centre of the universe, since this would imply a "special" point in the universe.
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