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Re: closed universe, flat space?
Posted:
Apr 29, 2013 2:05 PM


On Apr 24, Shmuel (Seymour J.) Metz <spamt...@library.lspace.org.invalid> wrote: > >>Supposedly, our universe is closed and finite, > >>although the geometry and topology isn't precisely > > >>known. This means a straight line (geodesic) > >>traveler must return to his starting > >> point, yes/no? Hence, curved space. > > >>At the same time, astronomers claim, that space > >>is flat, to the precision of their measurements. > > >>So, space is closed, but also flat... back in > >>my day, they had something called a logical > >>contradiction...
> No, the questions are why the OP is making a false > claim and and why the OP is falsely claiming a > logical contradiction. > > "Supposedly, our universe is closed and finite" > is untrue; what is true is that GR allows for the > possibility and that a sufficiently > latge density of matter would require it. The observed > density isn't large enough.
First, it's still unsettled. Second, for the purposes of this question  its motivation  we can hypothesize a closed universe.
> What is worse is that there is no logical > contradiction between a > closed universe and a flat universe.
1) "The earth is flat." 2) "If you drive/sail in a straight line, you return to your starting point."
Contradiction. QED
It could hardly be simpler.
 Rich



