In general the Universe is flat space.
The masses in the Universe are very few.
The distances between stars are very far.
What this means is that if you go into space far from massive bodies
and locate three ships far apart in a giant triangle, the angles of the
triangle will add up to 180 degrees, just as Euclid states in plane geometry.
2.
But Einstein ( GRT ) and others thought that the Universe was circle space.

Question.
Is the Universe ( as whole ) cold flat Euclidean space
or cold Einsteinium circle space ?
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Sado, all trajectories are curved( Einsteinium ) but may appear
straight( Euclidean ) over short enough distances.

Rybo
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Sadovnik.
1.
“An implication of Einstein’s theory of general relativity is that
Euclidean geometry is a good approximation to the properties
of physical space only if the gravitational field is not too strong”

Thus, if you meet with a strong gravitational field,
Euclidean geometry breaks down.
2.
The masses in the Universe are very few.
The distances between stars are very far.
So, most time quantum of light must go straight and
only meeting a rare star his trajectory will break down.
3.
The cold Euclidean space is Origen.
The Einsteinium space is Secondary.
The cold Euclidean space is Origen and it is Vacuum.
The Einsteinium space is Secondary and it is Gravity space.

Not the reverse.
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Best wishes.
Israel Sadovnik. / Socratus.
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