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Re: closed universe, flat space?
Posted:
Apr 24, 2013 5:08 PM


On Apr 23, 12:23 pm, RichD <r_delaney2...@yahoo.com> 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 > poiint, yes/no? Hence, curved space.
First, we need to consider how one would observe his own local space. If his local space is curved, can he tell? Although this question addresses the borderline with philosophy, common sense should say that one cannot tell at all since his own set of rulers will be equally curved. Thus, every observer will always observe his own local space as being flat. Only after comparing with a remote space that one can tell whose space is curved relative to the other. Curved space can only be relative. Even if space curved back onto itself, one will eventually return to his original position in his infinite future. <shrug>
> At the same time, astronomers claim, that space is flat, to > the precision of their measurements.
Cosmology does not fall into the domain of astronomy. Cosmology is more like occult science where these guys try to create reality with pure speculations. <shrug>
Static remote space will always be observed as flat. One can only tell if the remote space is curved compared to his own local space by observing the geodesic behavior of an object. <shrug>
Of course, this is not GR says. GR is voodooism. <shrug>
> Usually, this is > accompanied by the comment that the universe is balanced > between infinite expansion, or eventual collapse, we can't > tell which.
With null vacuum density in mass, both the Newtonian universe and GR will result in an eventual collapse of the universe. By allowing a negative vacuum density, both will allow an expanding universe since negative mass manifests antigravity. <shrug>
> So, space is closed, but also flat... back in my day, they > had something called a logical contradiction, which was > considered a bad thing, but I guess times change... > viva progress 
That progress is assimilation of a religion in progress. It takes several generations for a religion to take hold, but it takes longer to wean these morons off that same religion. Better education seems not to help. <shrug>



