Phillip Helbig---remove CLOTHES to reply
wrote in message ...
In article , greywolf42
writes:

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[Phillip]
I think there is some confusion here. Yes, Omega (matter) is 0.3 or so.
If you count galaxies, you count matter.

[greywolf42]
You count apparent luminosity, not matter. And you convert that
apparent
luminosity to absolute luminosity based upon a theory of
distance-vs-redshift.
If your theory is wrong, so is your absolute luminosity. (The
absolute-luminosity
vs morphology relation is also based on the assumption of the big bang.)
If your absolute luminosity is wrong, then so is your mass estimate
(which
may have other errors, as well).

[Phillip]
No. Estimating the density by measuring luminosity
============================

One cannot 'measure luminosity.' It's simply not possible without first
making several assumptions. We *can* measure 'brightness' or 'apparent
luminosity.' To measure 'luminosity' (which for your uses means
'absolute
luminosity'), one must first determine the distance and net extinction of
the source. This requires at least two theoretical models.

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and assuming a
mass-to-light ratio (such as that of our galaxy), also known as Oort's
method, takes place in the LOCAL universe.

I'm not discussing multiple-universe theories. "Local" in true
distance-measuring systems only extends to 300 light-years or so (after
Hipparcos). Beyond that, we make theoretical assumptions.

Redshift-based distances don't play much of a role here.

You are incorrect. There are about a couple of dozen galaxies where
we have the ability to resolve Cepheid variables -- which are our only
reliable distance "standard candles" (pre-supernovae -- which is another
bag of worms). All distances to other galaxies are measured by
assuming the BB and Hubble constant.
===================================

OK, we count photons at the lowest level (or measure a current
proportional to the number of photons---or measure a voltage which,
given a resistance is related to the current: whatever).

OK, I believe we have corrected your misunderstanding (or sloppy
terminology) about the difference between brightness (or apparent
luminosity) and absolute luminosity.

What assumptions do you think are wrong?

The ones contained in the portions of my post that you snipped. So, I've
replaced them.

Sure, any measurement is a long
chain from the actual measurement to the quantity of interest, but that
in itself is not a criticism.

It is if you use a chain of assumptions that contain one theory, then
attempt to use the results of the chain to 'disprove' a different theory.

Russell and Whitehead once wrote a book on mathematics where they tried
to justify everything explicitly. It took them a large number of pages
before they got to 1 + 1 = 2. Useful, perhaps, for the philosophy of
mathematics, but not for buying potatoes at the market.

What's with the strawman argument? The point is simply the assumptions and
theories that are contained in the distance 'measurements' that you are
using.

(The fact that one gets the same result
as with more global methods is another argument in favour of the
(current, but probably relatively robust) standard model.)

What are the 'more global methods' to which you refer?

For H_0: the HST key project is relatively local, gravitational-lens
time delays are more global, and the CMB is very global.

Again, what are the 'more global *methods*' to which you refer?

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Other observations (CMB) indicate that the universe is flat.

If you start with some versions of the BB theory, yes. The CMB may
have
other meanings if you assume different theories.

Yes, the heavens could be full of angels with flashlights emitting
microwaves.
=================================

The point is that CMB measurements only indicate 'flatness' for the BB.
No matter how you denigrate competing theories.

Show me another theory with adjustable parameters which, when these
parameters are varied within some pre-CMB-knowledge ranges, is
compatible with the CMB data for only some combinations of parameters.
If the CMB is compatible with none, it's ruled out by the CMB. If it is
compatible with the whole range of parameters, it's not (yet) testable.

It's not necessary to match your long list of limitations. It is quite
obvious that if the BB requires the CMB to indicate 'flatness', this does
not affect what the CMB means to other theories.

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The point, here, was to show that all is consistent. If I have a theory
in which different lines of investigation lead to the same result within
that theory, without inserting this result from the start, then that is
an argument in favour of that theory.

True. However, there are no 'independent' lines of investigation here.
If
the BB theory is incorrect, then the masses used are incorrect. And the
'dark matter' amounts are incorrect. And the 'dark energy' amounts are
incorrect. Historically, every one of these 'new' additions to the theory
are ad hoc -- to avoid another 'problem' with the BB.
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It is somewhat older than the age of the oldest objects we know.

What numbers do you come up with? The 10-15 billion years required
by the (post Hipparcos) Hubble shift is significantly younger than the
18 billion year old globular clusters.
=================================

This estimate for globular-cluster ages is obsolete. What's your
reference?

It is not sufficient merely to claim an observation is 'obsolete,'
and then avoid my question entirely.

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Again, what specific numbers to you come up with for age of the universe
and
age of globular clusters?
==============================

You made the claim first. Give me a reference and I'll give you a
newer, better reference showing it to be wrong.

Um, no. *You* began with the statement (which you snipped, above) "It is
somewhat older than the age of the oldest objects we know." So, please back
up your statement. Then I'll be happy to find a competing reference for
you.

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All is quite consistent. This "standard model" is also compatible
with the m-z diagram for supernovae.

Only if you assume 'dark energy' as an additional ad hoc assumption.

It's not an assumption, it's an observation.
===============================

"Dark Energy" may not be observed. The observation is that the Hubble
constant is not linear at far distances. "Dark Energy" is the ad hoc
rationale to account for the observation (the new epicycle).

The point is that the non-linearity is NOT completely arbitrary, but is
easily explained by an idea which has been around for decades.

'Dark energy' has not been around for decades. It was not even floated
until the observations of supernovae disproved the linear Hubble assumption.

The m-z diagram for supernovae could as easily be explained by the modified
QM theory of JP Vigier. Which really *has* been around for decades. The
m-z curve is in fact a curve of the type predicted by Vigier's theory. So
Vigier's theory covers the Hubble shift in it's entirety. It's still 'ad
hoc', but it's only one ad hoc. The BB theorists have had to create yet
another new ad hoc form of physics to 'explain' the new observations: 'dark
energy' (wich has negative gravitation, unlike any other prior form of
energy or matter) .

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Suppose someone gives me a paper bag, and I don't know if it is full of
air or lead. If it feels heavy, I can say that there is something
inside other than air, even if I don't know what it is.

Who said that it only held air or lead? 10 pounds of air is the same as
10
pounds of lead. Or a microgram of air and a microgram of lead.

"Dark energy" is just a modern sexy name for the cosmological constant
(with the possibility that the equation of state is perhaps different
than that of a pure cosmological constant). You make it sound like ANY
observed m-z diagram could be made compatible with the data. This is
not true.

No need to distort my position with a strawman argument. I simply note
that
the "amount" and 'characteristics' of "dark energy" are backfit to the
observed m-z diagram.

(In addition, it looks like the equation of state is that of
a pure cosmological constant.)
================================

Equations of state are theoretical constructs. The observation is
simply that the "Hubble constant," isn't constant.

You are displaying extreme lack of knowledge here. The term "constant"
in "Hubble constant" means that, at a given time, it is constant
everywhere in the universe.

The Hubble constant was defined in the 1920's to mean the relation between
the distance of a galaxy (containing a resolvable Cepheid variable) and the
redshift of the light from the galaxy. There is -- and was -- no additional
theoretical baggage about being constant 'at a given time'.

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See above. They don't have to explain it. They point out that THERE
IS
NO REASON TO EXPECT IT TO BE FLAT. Their book is concerned
mostly with measuring Omega (matter). At the time, there was no
strong
evidence for a cosmological constant, so they favoured a model with
lambda=0, pointing out even then that lambda=0.7 also fits the data
and
would be a viable choice. The universe doesn't have to be flat, but
it
CAN be flat, or close to it, as current observations seem to indicate.

I thought that GUTs require omega = 1.0. Are they all wasting their
time?

Are you taking it as an established fact that GUTs are true---in
contrast to the big bang? Give me some evidence that I should believe
that a GUT---in particular, one requiring omega = 1.0---is true.
===============================

Another strawman argument. No, I'm not assuming GUTs are true. But
they are popular.

Creationism is popular in much of the U.S. And your point is?

My point is contained in the rest of the paragraph that you 'invisibly'
snipped:

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Frankly, since the all predicted the decay of the proton --
and protons have not been seen to decay -- I conclude that GUTs are false.
(Someday I may be proved wrong. But after three major theoretical
'revisions' to get out from under observation, I'm not holding my breath.)

And why did the 'big bang' efforts of 20 years ago all focus on the
necessity of 'flatness.'

Because it was perceived to be a problem. That's why Coles and Ellis
wrote their book, to set the record straight.
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Excellent. Another physics myth torpedoed.

True science is self-correcting.

It's too bad we don't have more 'true science.'

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We all agree that Omega (matter) is
0.3. BUT WE DON'T KNOW WHAT MOS OF THIS MATTER IS.

Then there's little basis for the agreement, don't you think?

No. If the lights go out, we all agree that it is dark, though we might
not know the cause, and our best guesses might disagree.

Then there's little basis for the agreement as to the cause of the
blackout.
All we know is that there is something wrong.

Most astronomers
agree that lambda is 0.7. What lambda "IS" is a separate question.

It's not seperate at all. If you don't know what it 'IS', then you
can't know what the measurement of that unknown is.

Rubbish. If I weigh a container, I know its weight, even if I don't
know what is inside.

If you don't agree on the theory used to 'weigh' the container, you don't
even know that much.

See any of a number of papers on "cosmic concordance".

I meant the observations to which *you* were referring. I don't insist
on a complete list. Just a few examples.

Those ARE the observations to which I am referring.

*What* are the observations to which you are referring, specifically?

[Again, *what* are the observations to which you are referring?]


It's kind of
like the measurement of Avagadro's number a hundred years ago; more
than any one observation, this proof that atoms are real came mostly
from several independent methods giving the same result.

Actually, atomic theory was fought tooth-and-nail by the positivists.

And they lost.

And yet "modern physicists" continued to apply the positivistic method.
Equations are all.

That depends on which 'Big Bang' theory you refer to when you say "THE"
big-bang theory. "THE" (most popular) BB theory contains inflation.
Which makes statements of the values of omega and lambda.

At most, it would claim that the sum is 1. However, even if it is ruled
out, the evidence for the big bang still stands.

To which specific 'Big Bang' theory(ies) are you referring?

So Coles and Ellis do not share the commonly-accepted view that there
really *was* a 'flatness problem.' However, everyone understands what
the 'classical flatness problem' *was.* Even if Coles and Ellis
believe
that this 'problem' was more 'myth' than 'problem.'

It is no longer "commonly accepted" except among those who have not
followed the progress of science in this field.
===============================

But you still understand what the perceived problem was. Hence, there
is no need to imply that there never was a perception of the problem.
And no need to denigrate others for addressing the 'problem.'

Only if the problem has long since been solved.

A series of 1997 "lecture notes" does not constitute "long since solved!"
Even if it is published in a book by Cambridge University Press.

Galileo was wrong about
the tides, but there is no point in coming up with some theory other
than the differential attraction of the moon to explain his fault.

Another strawman argument.

greywolf42
ubi dubium ibi libertas