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Topic: closed universe, flat space?
Replies: 48   Last Post: May 5, 2013 2:45 PM

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 Koobee Wublee Posts: 1,417 Registered: 2/21/06
Re: closed universe, flat space?
Posted: May 5, 2013 1:45 AM

Dan <dan.ms.ch...@gmail.com> wrote:
> On May 4, 2:48 am, RichD <r_delaney2...@yahoo.com> wrote:

> You can't actually fold a blanket into a toroid .
> This is the 'intrinsic curvature' of the toroid .
> http://www.rdrop.com/~half/math/torus/torus.curvature.map.png

That looks like an ordinary toroid to Koobee Wublee. <shrug> Please
keep in mind that Dan is no God. He cannot fold any 3-D shape and
claiming 4-D, 5-D, 6-D, etc. <shrug>

> >So you're saying, that an inhabitant of a toroid or
> >cylinder - on its 2-D surface - cannot draw any shape
> >which will tell them it's warped? I find that hard to swallow.

>
> I can see it's warped - if I'm not in the cylinder surface .
> But the guy in the cylinder surface only interacts with stuff from
> WITHIN the cylinder surface .

Yes, the local guy cannot see its own space being warped. In any
direct observations, all space or spacetime should appear to be flat
to the same observer. Thus, the curvature of space is very much
relative. However, to account for gravity, time dilation must be
absolute. That means you can always tell someone whose local clock
tick rate is slower than anyone else, or else, there would be no
gravity and laws of physics. It is now becoming so obvious that to
mix curved space which is relative and time dilation which must be
absolute is getting very ludicrous. <shrug>

> That means that when you fold a paper into a cylinder , light travels
> along the folded path . Perception gets curved along with the objects
> of perception , resulting in apparent flatness. And that's good enough
> for physicists , since they can't get out of the universe , or the
> cylinder .

No, it does not mean you can fold a piece of paper and create 4-D, 5-
D, 6-D, etc. Perhaps, Dan can only fool grade school kids and also
self-styled physicists. <shrug>

> If he could go around the cylinder (leaving a mark at his starting
> point) he'd see it's closed .If the cylinder were big enough, he would
> think he's living in an infinite flat space. However, closure is a
> global property. Curvature is a local property. He still wouldn't be
> able to tell if he's in a round cylinder , an oval cylinder, a
> "flattened cylinder" , an infinitely long parallelepiped
> http://ars.els-cdn.com/content/image/1-s2.0-S0021999104001500-gr1.jpg
> , etc .

Has it occurred to Dan that relationship between two observations is a
mathematical mapping. When an observer sees an observed dimension
able to curve back onto itself in a finite fashion, the same would be
observed to span infinity to that local observer? That is the true
Riemannian geometry not Dan?s Bollywood/Hollywood mumble jumbos.
<shrug>