Flat Earthers back in charge of Cosmology?

On Wed, 21 Nov 07, Phillip Helbig wrote:
(Eric Flesch) writes:
I specified WMAP. ... I doubt that such a uniform background
with a few wrinkles truly demonstrates a flat universe.

Flatness implies Omega + lambda = 1. The CMB alone cannot, without
additional assumptions, determine Omega and lambda well separately, but
can determine their sum quite well. This is actually a very strong
signal.

I confess this is where my understanding falls short, as it seems
there must have been a lot of prior construction to be able to
calculate the sum of omega and lambda from that. Surely there are
many places where the ladder could have been leaned against the wrong
wall. (apologies for my lack of specificity)

The fact that a black-body spectrum was predicted for the CMB and that
it has been observed are very significant.

Yes, but not terribly material to the issue of a flat universe, unless
you are incorporating "inflation" into it, along with the idea that
inflation was the progenitor of the flat universe, which is a big
circular assumption of the kind of which I speak.

... within the context of Friedmann-Lemaître
cosmology, the curvature is everywhere the same. So, when we say "the
universe is (nearly) flat", we mean that it is flat even on large
scales, not trivially flat on local scales. It is the former that WMAP
measures.

Well, that it is worked to do so, after starting with FRW, yes.

I would like to point out a fact about hyperbolic space which is not
always appreciated: It is mandatory that a hyperbolic space be
enclosed by a spherical, as hyperbolic space carries with it an
asymptote as a boundary point, i.e. the line in the cone
x0^2-x1^2-x2^2 ... -xn^2 = 0. It follows that the boundary DHn is a
sphere. This leads to its enclosure (embedment) within a spherical
manifold. So at very large distances, the hyperbolic manifold is
overtaken by the spherical.

OK, that was hand-waving. Wish I could do better. Could I have done
better 1000 years ago, when talking about the flat Earth? I don't
know. But I am no happier about the flat universe today, than I would
have been with the flat Earth back then. This is my predicament. I
hope some of you erudite gentlemen can share these feelings.

(Eric Flesch) wrote:
Oh No wrote:
Thus spake Eric Flesch

Sure, the universe is locally flat, but so is
the Earth.

So there is HUGE evidence that the
universe is flat everywhere?

Let's see. Analogy time. Everywhere I look, without
exception, and in no matter in how much detail I
measure, from body mass to ear shape to tail length
to replicated genomes, mixing Homo sapiens and Canus
lupus in equal parts, I see werewolves. There is
nowhere I can point my eyes to rest them from the
sight of frolicking werewolves. Is that HUGE
evidence that the werewolf theory is true, or is it
"mere" evidence because it is all interrelated?

Evidence that is clear and non-circular?

No matter how many times you explain yourself, I
fail to find anything convincing in your claim that
the flat universe theory presupposes its conclusion
in drawing that conclusion. Could you show your work
in _much_ greater detail?

What is the best such evidence?

As far as I know, WMAP is the only evidence.

Everywhere we look, without exception, and in
however much detail within our powers we
investigate, we see the blackbody remnant radiation
of the earliest possible electromagnetic radiation
from the instant the universe stopped being opaque,
we see structure in it that predicts well the massy
component arrangements of the universe we see, and
at every angular resolution and wavelength aperature
we measure, that evidence predicted and now better
measured confirms that the universe is flat. Is that
HUGE evidence that the "flat universe" theory is
true, or is it "mere" evidence because it is all
interrelated?

Considering the FRW model antedates WMAP (and
Boomerang) by a few decades, they would have
walked a long plank over a hypothetical "flat
universe". If they really have no evidence other
than that, then I dare say a large scientific
establishment has been built up on an assumption.

Would you deny werewolves to exist as they chewed on
your flesh, calling that universally visible
werewolf evidence "an assumption"?

If not, why do you treat the WMAP evidence coursing
through your very flesh from every possible
direction any differently?

Yep, there are three viable alternative topologies
for the universe, spherical, hyperbolic, and
"flat". Only one of them can win, monkey odds rule
without any starting evidence or presuppositions.
What is it about the winner being the choice that
agrees with everyday experience that offends you so?

Remember, "flat earth" was a theory held by mostly
cranks living far from the sea or deep in theistic
denial at every age. As far back as we have records
kept of "science", we have scientists confirming and
measuring the curvature of the earth, sometimes with
remarkably modern looking results considering their
tools were sticks and string.

"Spherical Earth", or at least Earth's curvature,
was never in any doubt among the educated, the
rational, or the normally observant. "Spherical
earth" was the theory that agreed with everyday
evidence, and it turned out to be the correct one.

Now, from as far away as we normally go to look,
Earth looks very like a ball.

http://antwrp.gsfc.nasa.gov/apod/ima...kayuga_big.jpg

Now, from as far away as we are situated from where
to look, the universe looks topologically flat. That
doesn't mean things are the least bit boring out
the

http://antwrp.gsfc.nasa.gov/apod/ima.../arp87full.jpg

[How I would _love_ to understand the math that
predicts _that_ result!]

It just means things are less than completely
counterintuitive.

No topology surprises here folks, please just move along.

xanthian.

Eric Flesch wrote:

I would like to point out a fact about hyperbolic
space which is not always appreciated: It is
mandatory that a hyperbolic space be enclosed by a
spherical, as hyperbolic space carries with it an
asymptote as a boundary point, i.e. the line in
the cone x0^2-x1^2-x2^2 ... -xn^2 = 0. It follows
that the boundary DHn is a sphere. This leads to
its enclosure (embedment) within a spherical
manifold. So at very large distances, the
hyperbolic manifold is overtaken by the spherical.

That would mean that given a line and a point
separate from that line, there were at the very same
time, "zero" and "many" parallel lines to the first
line through that off-line point. Are we talking
about the same concepts of a space having a
geometry/topology?

OK, that was hand-waving.

A bit more than that.

I think you've just denied the mathematical
meaningfulness of "counting" with that claim, since
the concept "lines being parallel" explicitly
considers behavior "to infinity".

xanthian. Granted, "calculus on manifolds" wasn't a
class I understood all that well in college.

Thus spake Eric Flesch
On Wed, 21 Nov 07, Oh No wrote:
Thus spake Eric Flesch
Sure, the universe is locally flat, but so is the Earth. So there is
HUGE evidence that the universe is flat everywhere? Evidence that is
clear and non-circular? What is the best such evidence?

As far as I know, WMAP is the only evidence.

Considering the FRW model antedates WMAP (and Boomerang) by a few
decades, they would have walked a long plank over a hypothetical "flat
universe". If they really have no evidence other than that, then I
dare say a large scientific establishment has been built up on an
assumption. There's a lot of inertia there. Hey, maybe if I shout at
the big brick wall...

You are wrong. Before the WMAP/Boomerang data, and before the Supernova
data, there was no reason to assume a flat universe. FRW models come in
nine major types, with a couple of subcategories thrown in for good
measure. If it had not been for the missing matter problem, and the
timescale problem, I would think theoretical prejudice was most strongly
in favour of a closed positive curvature model.

Hey people, IT'S A HYPERBOLIC MANIFOLD. There's NO ACCELERATING
EXPANSION. NO DARK MATTER. NO DARK ENERGY.

Shouting does not work. You have at least to start with a rigorous data
analysis in the context of a valid cosmological model. At the moment the
only models which are even reasonable are the FRW models based in
standard gtr. The outcome of the data analysis in those models is quite
clear, and gives a flat model with accelerating expansion, dark matter
and dark energy.

Of course that does not mean that those are the only possible models. We
know that gtr needs a fix to make it compatible with quantum theory and
even with classical electromagnetism. We also know there are a range of
astronomical measurements, e.g. MOND, Pioneer, lensing profiles, which
do not make sense in the standard model. Imv the only place where any
sort of fix or adjustment is reasonable, or perhaps even possible is the
connection. That was also Einstein's view. The result of replacing the
affine connection with the teleconnection is a closed universe, no
missing matter, no accelerating expansion, no dark matter, no dark
energy, no MOND, and an explanation for Pioneer acceleration.

[Mod. note: can I remind posters of the speculativeness criterion for
s.a.r. postings -- it would be preferable not to assert that
non-standard models explain phenomena without some qualification (or
at least a reference to publications where these claims can be
examined). Thanks -- mjh]

Regards

--
Charles Francis
moderator sci.physics.foundations.
substitute charles for NotI to email

Thus spake Oh No
[Mod. note: can I remind posters of the speculativeness criterion for
s.a.r. postings -- it would be preferable not to assert that non-
standard models explain phenomena without some qualification (or at
least a reference to publications where these claims can be examined).
Thanks -- mjh]

The fact that Einstein pointed out the inconsistency between gtr and
classical electromagnetism nearly eighty years ago should need no
reference, even if it has been studiously ignored in standard cosmology.
This being the case you might perhaps consider that standard models are
at least as speculative at any based on the removal of that
inconsistency, and remember your own guideline that argument from
authority, in this case the authority being peer reviewed publication,
is not a proper scientific criterion. Mathematical rigour, otoh is.

[Mod. note: a criterion might be to consider whether a reader new to the
newsgroup could be expected to figure out what you're talking about
and what its status is. They can do that for the standard model by
picking up an undergraduate cosmology textbook: non-standard ideas
require more explanation and perhaps more caveats -- mjh]

I have previously given reference to papers which can be examined.

gr-qc/0508077
A Relational Quantum Theory Incorporating Gravity

gr-qc/0604047
Does a Teleconnection between Quantum States account for Missing Mass,
Galaxy
Ageing, Lensing Anomalies, Supernova Redshift, MOND, and Pioneer
Blueshift?

I will not say they are perfect, and am working on a new and more
accessible account. Publication will depend on such things as finding a
reviewer who does not think, for example, that if a curve has the same
gradient as its tangent at a point, then that curve has that gradient
everywhere, and is thus a straight line.

More strictly, I should say, that if a manifold has the same metric as
its tangent space at a point, then the manifold has constant metric and
is flat; for a one dimensional manifold, this reduces to the previous
statement. This appears to be a case of that disease in applied
mathematics where people glibly write down, "let f=f(x)" instead of "let
f:x-f(x)", not realising that they have just said, let a function be
equal to one of its values. Similarly general relativists typically talk
of tensor fields (being tensor valued functions on coordinate space) as
tensors. This being so prevalent these days, I am starting to despair of
finding anyone who actually understands the subject.

Likewise peer reviewed publication of the empirical evidence appears to
depend on finding a reviewer who does not confess that he doesn't know
the difference between radial velocity and the component of velocity
parallel to an axis, or one who doesn't say the results must imply that
systematic errors on Hipparcos were more than four times greater than
published statistical errors, or other similar nonsense.


Regards

--
Charles Francis
substitute charles for NotI to email

On Thu, 22 Nov 07, Oh No wrote:
You are wrong. Before the WMAP/Boomerang data, and before the Supernova
data, there was no reason to assume a flat universe.

As explained in my posting "A Brief History...", Guth's inflation
*requires* a flat universe, so there's your reason.

Thus spake Eric Flesch
On Thu, 22 Nov 07, Oh No wrote:
You are wrong. Before the WMAP/Boomerang data, and before the Supernova
data, there was no reason to assume a flat universe.

As explained in my posting "A Brief History...", Guth's inflation
*requires* a flat universe, so there's your reason.

Perhaps, but it seems extraordinarily speculative to postulate inflation
during a time of the universe when we have every reason to believe, from
gtr, from quantum theory, and even from observation of isotropy, that
the very idea of spacetime structure had broken down and ceased to make
sense.

Regards

--
Charles Francis
moderator sci.physics.foundations.
substitute charles for NotI to email

In article ,
(Eric Flesch) writes:

On Wed, 21 Nov 07, Phillip Helbig wrote:
(Eric Flesch) writes:
I specified WMAP. ... I doubt that such a uniform background
with a few wrinkles truly demonstrates a flat universe.

Flatness implies Omega + lambda = 1. The CMB alone cannot, without
additional assumptions, determine Omega and lambda well separately, but
can determine their sum quite well. This is actually a very strong
signal.

I confess this is where my understanding falls short, as it seems
there must have been a lot of prior construction to be able to
calculate the sum of omega and lambda from that. Surely there are
many places where the ladder could have been leaned against the wrong
wall. (apologies for my lack of specificity)

It's not a trivial calculation. We are talking about several Ph.D.
projects to get to this conclusion. However, many people have obtained
the same result independently with different methods, so I would say
that it is a robust result, assuming basic stuff like general relativity
is valid.

The fact that a black-body spectrum was predicted for the CMB and that
it has been observed are very significant.

Yes, but not terribly material to the issue of a flat universe, unless
you are incorporating "inflation" into it, along with the idea that
inflation was the progenitor of the flat universe, which is a big
circular assumption of the kind of which I speak.

No, no, no. The black-body spectrum reinforces the idea that the CMB is
actually the "echo of the big bang" and not coming from some other
source. Obviously, we have to be sure that we are observing the "echo
of the big bang" before drawing conclusions which assume that that is
what we are looking at. The curvature signal in the CMB has nothing to
do with inflation, though. (Other aspects of the CMB, where the signal
is weaker, can be investigated as to whether they are consistent with
(some model of) inflation, but that is a different matter and
independent of the observed values of Omega and lambda. In other words,
the values of Omega and lambda we observe are quite secure. Another
question, to which inflation is one possible answer (but not the only
one), is WHY they have the values they do.)

OK, that was hand-waving. Wish I could do better. Could I have done
better 1000 years ago, when talking about the flat Earth? I don't
know. But I am no happier about the flat universe today, than I would
have been with the flat Earth back then. This is my predicament. I
hope some of you erudite gentlemen can share these feelings.

I think the comparison is bad. Even the ancient Greeks knew that the
Earth is a sphere (by watching lunar eclipses, by watching ships at sea,
by noting that the sun is higher in the south). Even in the middle
ages, the number of people who actually believed the Earth is flat is
exaggerated. (This was not the reason people thought Columbus was
foolhardy, but rather because they thought he underestimated the size of
the Earth, which he did, believing it was about 28.000 km in
circumference rather than 40.000. They were right and he was wrong.
They were correct in being sceptical about his ability to sail to Asia.
Of course, he never sailed to Asia (though he believed so all his
life).) The flat universe is something which is derived from
observational data. While there was a time during which it was espoused
with the same almost religious faith which simpletons might have had in
the flat Earth, today it is an observational result. Just because
someone believes something on faith doesn't mean that it has to be
wrong.)

In article ,
(Eric Flesch) writes:

On Wed, 21 Nov 07, Oh No wrote:
Thus spake Eric Flesch
Sure, the universe is locally flat, but so is the Earth. So there is
HUGE evidence that the universe is flat everywhere? Evidence that is
clear and non-circular? What is the best such evidence?

As far as I know, WMAP is the only evidence.

WMAP is perhaps the only experiment which, in itself, strongly indicates
flatness. But others do so less strongly, and various combinations of
experiments also indicate the same result strongly.

Considering the FRW model antedates WMAP (and Boomerang) by a few
decades, they would have walked a long plank over a hypothetical "flat
universe". If they really have no evidence other than that, then I
dare say a large scientific establishment has been built up on an
assumption. There's a lot of inertia there. Hey, maybe if I shout at
the big brick wall...

You seem to think FRW = flat. Where did you get that idea?

Hey people, IT'S A HYPERBOLIC MANIFOLD. There's NO ACCELERATING
EXPANSION. NO DARK MATTER. NO DARK ENERGY.

Your evidence, please?

Oh No wrote:
Thus spake Eric Flesch

As explained in my posting "A Brief History...",
Guth's inflation *requires* a flat universe, so
there's your reason.

Well, no.

The era of inflation was an era where the laws of
physics weren't the laws as they are today, because
(at least) two of the fundamental physical forces
hadn't yet differentiated themselves in a symmetry
breaking event, IIUC.

It very likely isn't sensible to talk about the
"flatness" of the universe, before its size reached
sufficient multiples of the Plank length, before the
changes in the structure of space slowed
sufficiently that the speed of light assumed a
value.

Before that, the concept of a measurement of
flatness to precision sufficient to compare to what
we measure today, is probably not even meaningful.

Again, IIUC, what that breaking symmetry did was
take a universe in which energy density fluctuations
putatively resembled white noise, and stretch its
structure out until the remaining fluctuations were
only very imperceptibly (though maybe only "in
comparison to the prior case") differentiable from
the mean value. On those barely perceptible
remaining density fluctuations, amplified by gravity
and time, rests the genesis of the current large
scale (filament and bubble) (and maybe "medium
scale" (individual galaxies and clusters thereof))
structure of our universe.

Guth's inflation didn't "require" a flat universe,
that's muddle talk. It _created_ a flat universe,
from one that was nothing like flat, more like
"chaotic", and did it using the energy provided by
the symmetry breaking that separated one fundamental
force into two.

Perhaps, but it seems extraordinarily speculative
to postulate inflation during a time of the
universe when we have every reason to believe,
from gtr, from quantum theory, and even from
observation of isotropy, that the very idea of
spacetime structure had broken down and ceased to
make sense.

Your sense/expression of time and causality is
backwards there.

_That_ universe was the original one, _ours_ is the
one which has "broken down", and one result of that
"breaking down" is the flatness we perceive.

Thus, "inflation" goes from that Ur-state universe,
via some symmetry breaking, to our broken-state
universe, and given the tremendous predictive power
of "inflation", the only "speculative" part of it
seems to be trying to understand _why_ such symmetry
breaking occurred, at a certain point of decreased
energy density, at all.

That seeking for some gut level comprehensible
"why" the events happened understanding of causality,
in the happenings of a universe unobservable to us
due to the uncertainty principle, is almost a "meta"
question about physics. There isn't much issue about
"whether" the events happened, any more, that I can
see, and certainly not much "visible to me"
controversy within mainstream cosmology about
whether "inflation" is the discipline's "received
wisdom" today. Efforts today seem to focusing on
filling in the details and understanding additional
implications of "inflation" , not on challenging the
base idea.

[All the above is entirely "to the best of my
understanding".]

xanthian.