Galaxies without dark matter halos?

wrote in message
...
On Thu, 25 Sep 2003, greywolf42 wrote:
-- I believe the original set of luminosity and
galaxy type was built by using distances determined with the Hubble
redshift method.

If by "the original set" you mean something like "The original set that
Hubble made" (or other decades old set), so what? It's not in use now and
the Hubble relation is still there.

If you mean that the Hubble constant is used the calibrate, say,
Tully-Fischer *TODAY* -That- -is- -*still*- -just- -flat- -wrong-. As an
almost trivial amount of reading would show you. People in fact calibrate
T-F
with different methods just to compare the results.

Then what is used? Why simply assert that I'm wrong? Why not mention the
physical process used to calibrate Tully-Fischer?

A list from an introductory text does not provide all the information
required to address the issue.

It does, however, point out how easy it would be for you to find such
information -if- you wanted to. Since you now imply that such intro texts
are too basic should I revert to an obvious reason other than lack of
knowledge why you would make an incorrect statement?

And I still recommend you read Shu.

Why add another text, since you apparently don't know what the reason is
yourself?

My point was that the (local) Cepheid
galaxies are the primary basis of the Hubble distance relation.

If that is you point, say it, not somthing else.

I did say it.

But even if the Chepeid distance is off by a factor of a million:
"Still it moves" --A plot of distance vs. redshift which is linear in
ly vs delta l/l is still linear when re-labeled parsecs vs. delta l/l
or cm or teraparsecs.

How does this relate to the calibration of the Tully-Fischer scaling law?

To generalize my point, using your classification scheme, the
intermermediate and global distance relationships (except for the
supernovae) were all founded on distances that were based on the Hubble
constant.

But this is not true.

I measure the distance to some galaxies using Cepheids & RR Lyae.

RR Lyrae stars are less luminous that Cepheids. Hence Cepheids determine
the maximum distance to which we have a non-redshift-based correlation.

I measure the 21cm line of these galaxies. I do a regression of
distance vs. line width. I measure the 21cm line width of a new
galaxie and use my regression result to calculate the distance.
I have not even measured a red shift yet, so how am I possibly
using the Hubble relation??

Because you are making the theoretical assumption that the cause of the
change in line width is velocity of the galaxy. Just like the assumption
that the cause of the hubble shift is velocity.

Which is why the universal distance scale shifted when Hipparcos
was actually able to measure the parallax of a Cepheid variable star.
Hipparcos found that Cepheids were closer than theoretically expected.
Which shifted 'in' the two dozen baseline galaxies. Which shifted the
Hubble constant. Which 'shrank' the rest of the universe.

Again, so what? In fact no, not "So what" --they corrected the error and
changed the distances. Something you repeatedly imply they don't do.

The point is, that if the long distance range was not based solely on the
hubble relation, then shifting in the 'hubble' galaxies would not have
affected the long distance scales. Because those 'other' methods wouldn't
change.

People have cross compared these where ever it makes sense. They know
when calibrating method A from method B and Method C from B errors build
up, both statistical & flaws in the methods. That is why you see them
delighted that -different- methods agree.

And most importantly, even if you do prove the units are wrong the
distance-redshift relation doesn't go away.

I have no idea why you think this is important, because I never claimed or
implied that the discussion was over 'units.' Nor did I imply that there is
no distance-redshift relationship in the nearer galaxies.

I once saw a plot of a set of random* galaxies plotted appearant size
vs. redshift. There was a Hubble law.

I presume you mean that they used the hubble constant to determine the
distances to those random galaxies.

If you can, explain it some
nonstandard way, but denial or misrepresentation of the observations
or observational methods isn't going to work.

Explain what? I've never denied the observations or the methods. I've
merely tried to point out to you that the conversion of the observations to
conclusions about distance in the far field are all based on the theoretical
assumption of the big bang. Hence, one cannot use these observations
themselves as support for the big bang -- because the distance were all
determined from that assumption.

greywolf42
ubi dubium ibi libertas

In article , greywolf42
writes:

The "dogma" has changed, motivated almost entirely by data. No-one ever
suggested that Omega was 0.3 and lambda 0.7 based on anything except
data. Thus, I would argue that the current standard model is primarily
data driven. Just because someone mistakenly elevates it to dogma
doesn't make it automatically wrong.

Dogma is not automatically wrong. (Just ask of the various churches.)
However, dogma is primarily of theoretical origin (or theological origin --
sometimes it's hard to divorce the two). The two values you provided are
based on the dogma that omega = 1.0.

We both agree that there was and perhaps still might be a dogma stating
that Omega_total (i.e. Omega_matter + lambda) must be 1, and that this
dogma, when first developed, didn't have sufficient motivation.
However, the values I mentioned above (0.7 and 0.3) are derived from
observations whether or not one believes this dogma.

The interesting question now is how close this sum is to 1: Within 10%?
1%? 0.1%?

In article , greywolf42
writes:

The "dogma" has changed, motivated almost entirely by data. No-one ever
suggested that Omega was 0.3 and lambda 0.7 based on anything except
data. Thus, I would argue that the current standard model is primarily
data driven. Just because someone mistakenly elevates it to dogma
doesn't make it automatically wrong.

Dogma is not automatically wrong. (Just ask of the various churches.)
However, dogma is primarily of theoretical origin (or theological origin --
sometimes it's hard to divorce the two). The two values you provided are
based on the dogma that omega = 1.0.

We both agree that there was and perhaps still might be a dogma stating
that Omega_total (i.e. Omega_matter + lambda) must be 1, and that this
dogma, when first developed, didn't have sufficient motivation.
However, the values I mentioned above (0.7 and 0.3) are derived from
observations whether or not one believes this dogma.

The interesting question now is how close this sum is to 1: Within 10%?
1%? 0.1%?

Ulf Torkelsson wrote in message
...
There is no such theoretical relationship as you imagine.

I wasn't the one that claimed there was.

For most
Hubble types you can find both small and large galaxies, and always
there is a significant spread in the luminosities.

You are correct, but -- again -- we aren't discussing the Hubble
classification scheme.

No, the Tully-Fisher scheme has never been calibrated based on the
Hubble constant, that is plainly wrong. There are also more distance
indicators than the Cepheids.

Well, yes. But the Cepheids provide the largest non-redshift assumption
distance scale.

May I suggest that you pick up the book:

Rowan-Robinson, M., 1985,
The cosmological distance ladder,
W. H. Freeman & Comp., New York

Rowan-Robinson describes in detail how you build up the cosmological
distance scale. You start with the primary indicators, cepheids,
supernovae, novae and RR Lyrae variables. You then use these to
calibrate new distance indicators, such as the size of HII-regions,
globular clusters, the brightest stars in the galaxies, the
Tully-Fisher relation and so on. In the end you can even use the
brightest cluster galaxies to determine the distances to clusters of
galaxies. Nowhere in this process do you use Hubble's constant.

You use the hubble constant anywhere outside the range of Cepheids. The
(fairly recent) supernovae calibrations were produced after all the others
were (i.e. Tully-Fischer relation) were already "set." Indeed, with a
publication date of 1985, the supernovae ladder won't be included.

Next time I'm at the library, I check out Rowan-Robinson.

greywolf42
ubi dubium ibi libertas

[Mod. note: quoted text trimmed. Please do this yourself. I have begun
rejecting, and will continue to reject, postings with excessive quoted
text -- mjh]

Ulf Torkelsson wrote in message
...
There is no such theoretical relationship as you imagine.

I wasn't the one that claimed there was.

For most
Hubble types you can find both small and large galaxies, and always
there is a significant spread in the luminosities.

You are correct, but -- again -- we aren't discussing the Hubble
classification scheme.

No, the Tully-Fisher scheme has never been calibrated based on the
Hubble constant, that is plainly wrong. There are also more distance
indicators than the Cepheids.

Well, yes. But the Cepheids provide the largest non-redshift assumption
distance scale.

May I suggest that you pick up the book:

Rowan-Robinson, M., 1985,
The cosmological distance ladder,
W. H. Freeman & Comp., New York

Rowan-Robinson describes in detail how you build up the cosmological
distance scale. You start with the primary indicators, cepheids,
supernovae, novae and RR Lyrae variables. You then use these to
calibrate new distance indicators, such as the size of HII-regions,
globular clusters, the brightest stars in the galaxies, the
Tully-Fisher relation and so on. In the end you can even use the
brightest cluster galaxies to determine the distances to clusters of
galaxies. Nowhere in this process do you use Hubble's constant.

You use the hubble constant anywhere outside the range of Cepheids. The
(fairly recent) supernovae calibrations were produced after all the others
were (i.e. Tully-Fischer relation) were already "set." Indeed, with a
publication date of 1985, the supernovae ladder won't be included.

Next time I'm at the library, I check out Rowan-Robinson.

greywolf42
ubi dubium ibi libertas

[Mod. note: quoted text trimmed. Please do this yourself. I have begun
rejecting, and will continue to reject, postings with excessive quoted
text -- mjh]

Phillip Helbig---remove CLOTHES to reply
wrote in message ...
We both agree that there was and perhaps still might be a dogma stating
that Omega_total (i.e. Omega_matter + lambda) must be 1, and that this
dogma, when first developed, didn't have sufficient motivation.
However, the values I mentioned above (0.7 and 0.3) are derived from
observations whether or not one believes this dogma.

My understanding of the source of the omega = 0.3 was the BB with Omega =
1.0. May I ask what sources for 0.3 and 0.7 are you using?

The interesting question now is how close this sum is to 1: Within 10%?
1%? 0.1%?

I belive it's as arbitrarily close as the assumptions in your calculations.

greywolf42
ubi dubium ibi libertas

[Mod. note: quoted text trimmed -- mjh]

Phillip Helbig---remove CLOTHES to reply
wrote in message ...
We both agree that there was and perhaps still might be a dogma stating
that Omega_total (i.e. Omega_matter + lambda) must be 1, and that this
dogma, when first developed, didn't have sufficient motivation.
However, the values I mentioned above (0.7 and 0.3) are derived from
observations whether or not one believes this dogma.

My understanding of the source of the omega = 0.3 was the BB with Omega =
1.0. May I ask what sources for 0.3 and 0.7 are you using?

The interesting question now is how close this sum is to 1: Within 10%?
1%? 0.1%?

I belive it's as arbitrarily close as the assumptions in your calculations.

greywolf42
ubi dubium ibi libertas

[Mod. note: quoted text trimmed -- mjh]

greywolf42 wrote:

Ulf Torkelsson wrote in message
...
No, the Tully-Fisher scheme has never been calibrated based on the
Hubble constant, that is plainly wrong. There are also more distance
indicators than the Cepheids.


Well, yes. But the Cepheids provide the largest non-redshift assumption
distance scale.

This is simply incorrect. The cepheids can be, and have been, used
to calibrate other distance indicators such as the sizes of the
largest HII-regions of the galaxies, the brightnesses and sizes of the
brightest galaxies in clusters of galaxies, the Tully-Fisher relation
and so on. None of these distance scales will then depend on the value
of Hubble's constant as you have claimed.

Ulf Torkelsson

[Mod. note: reformatted -- mjh]

greywolf42 wrote:

Ulf Torkelsson wrote in message
...
No, the Tully-Fisher scheme has never been calibrated based on the
Hubble constant, that is plainly wrong. There are also more distance
indicators than the Cepheids.


Well, yes. But the Cepheids provide the largest non-redshift assumption
distance scale.

This is simply incorrect. The cepheids can be, and have been, used
to calibrate other distance indicators such as the sizes of the
largest HII-regions of the galaxies, the brightnesses and sizes of the
brightest galaxies in clusters of galaxies, the Tully-Fisher relation
and so on. None of these distance scales will then depend on the value
of Hubble's constant as you have claimed.

Ulf Torkelsson

[Mod. note: reformatted -- mjh]

greywolf42 wrote:

Ulf Torkelsson wrote in message
...
No, the Tully-Fisher scheme has never been calibrated based on the
Hubble constant, that is plainly wrong. There are also more distance
indicators than the Cepheids.

Well, yes. But the Cepheids provide the largest non-redshift assumption
distance scale.

This is simply incorrect. The cepheids can be, and have been, used
to calibrate other distance indicators such as the sizes of the
largest HII-regions of the galaxies, the brightnesses and sizes of the
brightest galaxies in clusters of galaxies, the Tully-Fisher relation
and so on. None of these distance scales will then depend on the value
of Hubble's constant as you have claimed.

Ulf Torkelsson

[Mod. note: reformatted -- mjh]