the primordial vacuum had a constant intrinsic negative spacetime curvature, meaning that it has to expand exponentially (de Sitter spacetime).
How much more lucky can the universe be? " de Sitter was born" to give it "expanding exponentially space-time", which was constan
t! Can I ask: How does fit the "inflation" in this "constance"?
I don't think that de Sitter had anything to do to influence the universe. :-( The universe is a "fact" that we study; not "influence".
Some things can never be observed directly - just their influences are observable and that's what science is really about
Which means that, since we observe is influence
every Christmas morning, with our kids, Santa Claus as always been "scientifically" accepted and we didn't realize it. I don't like this "what science is really about" argument at all. It applies to anything.
Add to that the radiation, baryonic and dark matter's positive spacetime curvature that balances out de Sitter's spatial part, and you have a spatially flat, expanding universe.
Exactly! Simply because matter " curves" positively space-time, says the interpretation of Einstein/Newton bad mixture. It took a long time before the universe realized that it was Euclidian; way later than the birth of Euclid. In fact, it had to wait for de Sitter and Newton + Einstein, to be born.
I'm almost convince that the observer "creates" the "observation". In reality, we can specify that the "observer" creates is "interpretation" of the observation.
Now, we have a negatively curved space-time "created" by de Sitter, with the added "insertion" of positively curved space-time of "creators" Einstein/Newton, which sums up to Planck satellite observation
of a balanced
"flat" expanding universe (not space-time, mind you), that we "interpret" as "needed
". So, since expansion is accelerating
, that balanced
"flat" expanding universe as a negatively curved expanding "expansion
". Then we accept that space
is "flat" but space-time
is negatively curved. Which means that when matter/radiation was more important than "vacuum energy
", the space was still "flat" but space-time was balanced "positively" curved
So today we have a "curved" space-time
with a "flat" space,
because of the negatively curved space-time (de Sitter). Which, consequently, means that space is "flat
" but "time" is curved
Finally we have answered the question: Is the universe a sphere, hyperbolic or flat?
The answer is: it's all three depending of the epoch we're talking about.
Science cannot be "satisfying for everybody" more than that, can't it? Which explains perfectly
the actual "consensus" in the scientific "college". And furthermore, it cannot be more clear and logical
than this; thank you.
As a matter of fact, we can even conclude that "critical density" was always = 1 for space; but not = 1 for time. Which, evidently, explain the different epochs. CQFD.
But, again, scientists say: "we haven't found all the answers explaining perfectly all of this
; we are still searching" (I'm beginning to think they should ask J. K. Rowling for answers).
The cosmological constant is the simplest and most limited in scope (of the three) and has been pinned down with reasonable accuracy by observation.
You're talking here of the "inobservable" dark energy
(cosmological constant); aren't you?
Science is a serious study; someday, scientists will perceive it this way. I hope.
Maybe, then, they will realize that our actual technology is way far ahead of previous ones
and they will accept to put aside all previous interpretations
and start all over with cleared eyes
to "interpret" the lasts observations; instead of trying to fit it to past interpretations
given by less precise observations.
By the way, you are right: CMB is observed exclusively in the micro-wave spectrum
. This is the exact answer I was arguing for. Thank you.