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A comment on The Last of the Universe’s Ordinary Matter Has Been Found. Parent comment

Re:The Last of the Universe’s Ordinary Matter Has Been Found by jeremyjh on Monday September 10, 2018 @07:08PM (#17955904)
Imagine you are in inside of a giant beach ball, walking on the surface. You will never find an edge, and it is meaningless to talk about such a thing. Yet the space is finite.
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Re:The Last of the Universe’s Ordinary Matter Has Been Found by jaipilot747 on Monday September 10, 2018 @10:39PM (#17956811)
A beach ball has no "edge", but it definitely has a boundary surface, and everything on the other side of this surface is "not beach ball".

Now what lies beyond the universe's boundary surface? Is such a surface even present?

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Re:The Last of the Universe’s Ordinary Matter Has Been Found by jeremyjh on Tuesday September 11, 2018 @12:59PM (#17961427)
That is indeed where the analogy starts to crumble. The reason is that space itself is curved. It is curved by the matter inside it. Still the property holds that if you travelled far enough fast enough you’d come back to where you started.
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Re:The Last of the Universe’s Ordinary Matter Has Been Found by anyfoo on Monday September 10, 2018 @08:29PM (#17956248)
Conversely, the surface of the beach ball has no "center". It's also fun to realize if you blow that beach ball up, from the point of view of any point on the ball, all other points grow further away.
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