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

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dan.ms.chaos@gmail.com

Posts: 409
Registered: 3/1/08
Re: closed universe, flat space?
Posted: May 4, 2013 2:46 AM
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On May 4, 2:48 am, RichD <r_delaney2...@yahoo.com> wrote:
> On Apr 29, Dan <dan.ms.ch...@gmail.com> wrote:

> Into what?  A toroid?
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

>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 .
http://www.youtube.com/watch?v=C8oiwnNlyE4

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 .

An easy way to understand this is :
Imagine you were turned upside-down (ignoring gravitational
effects) . How could you tell that you got turned upside down? By
looking at the rest of the world, that is still right-side up. But, if
you look at your hand , it still looks unchanged from when you were
normal-oriented . You can't tell if you're upside down by looking at
your hand .
Now image you couldn't look at the rest of the world . You could only
look at yourself .
Could you tell if you were upside-down or ringside-up ? Upside down
with respect to what? Would it even matter?
That's the situation in Riemanian Geometry .




Date Subject Author
4/23/13
Read closed universe, flat space?
Rich Delaney
4/23/13
Read Re: closed universe, flat space?
Poutnik
4/24/13
Read Re: closed universe, flat space?
Shmuel (Seymour J.) Metz
4/29/13
Read Re: closed universe, flat space?
Rich Delaney
4/23/13
Read Re: closed universe, flat space?
kenseto
4/24/13
Read Re: closed universe, flat space?
JT
4/24/13
Read Re: closed universe, flat space?
herbert glazier
4/24/13
Read Re: closed universe, flat space?
Double-A
4/23/13
Read Re: closed universe, flat space?
Nicolas Bonneel
4/29/13
Read Re: closed universe, flat space?
Rich Delaney
4/29/13
Read Re: closed universe, flat space?
Mike Terry
4/23/13
Read Re: closed universe, flat space?
xxein
4/23/13
Read Re: closed universe, flat space?
Brian Q. Hutchings
4/23/13
Read Re: closed universe, flat space?
Butch Malahide
4/23/13
Read Re: closed universe, flat space?
Newberry
4/24/13
Read Re: closed universe, flat space?
Koobee Wublee
4/24/13
Read Re: closed universe, flat space?
dan.ms.chaos@gmail.com
4/24/13
Read Re: closed universe, flat space?
Koobee Wublee
4/24/13
Read space is locally curved, as has been measured
Brian Q. Hutchings
4/25/13
Read Re: closed universe, flat space?
dan.ms.chaos@gmail.com
4/25/13
Read Re: closed universe, flat space?
herbert glazier
4/25/13
Read Re: closed universe, flat space?
dan.ms.chaos@gmail.com
4/25/13
Read Re: closed universe, flat space?
bradguth@gmail.com
4/27/13
Read Re: closed universe, flat space?
Brian Q. Hutchings
5/4/13
Read Re: closed universe, flat space?
bradguth@gmail.com
5/5/13
Read Re: closed universe, flat space?
Brian Q. Hutchings
4/25/13
Read Re: closed universe, flat space?
Koobee Wublee
4/25/13
Read Re: closed universe, flat space?
dan.ms.chaos@gmail.com
4/25/13
Read Re: closed universe, flat space?
Koobee Wublee
4/25/13
Read closed universe, flat space, ignore Minkowski's worse nD geometry;
thank you
Brian Q. Hutchings
4/26/13
Read Re: closed universe, flat space, ignore Minkowski's worse nD
geometry; thank you
Brian Q. Hutchings
4/27/13
Read curved space and/or curved time (time is the "real, scalar" part of
vector mechanics -- like a God-am clock
Brian Q. Hutchings
4/27/13
Read Re: curved space and/or curved time (time is the "real, scalar" part
of vector mechanics -- like a God-am clock
Brian Q. Hutchings
4/27/13
Read Re: closed universe, flat space?
Tom Roberts
4/27/13
Read Re: closed universe, flat space?
Koobee Wublee
4/27/13
Read Re: closed universe, flat space?
Brian Q. Hutchings
4/29/13
Read Re: closed universe, flat space?
Rich Delaney
4/29/13
Read Re: closed universe, flat space?
dan.ms.chaos@gmail.com
4/29/13
Read Re: closed universe, flat space?
Koobee Wublee
4/30/13
Read Kepler uncovered the curvature via his three orbital constraints
(reciprocal of diameter)
Brian Q. Hutchings
4/30/13
Read Minkowski was an otherwise-great geometer!
Brian Q. Hutchings
5/1/13
Read Minkowski, Minkowski, Minkowski -- say it, againsville
Brian Q. Hutchings
5/1/13
Read Kepler's cosmological curvature thingies
Brian Q. Hutchings
5/3/13
Read Re: closed universe, flat space?
Rich Delaney
5/4/13
Read Re: closed universe, flat space?
dan.ms.chaos@gmail.com
5/4/13
Read Re: closed universe, flat space?
dan.ms.chaos@gmail.com
5/4/13
Read Re: closed universe, flat space?
dan.ms.chaos@gmail.com
5/5/13
Read Re: closed universe, flat space?
Koobee Wublee
5/5/13
Read eight to the bar -- Daddy!
Brian Q. Hutchings

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