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deSitter
Still in Old School


Reged: 12/09/04

Re: Red/Blue shift due to Doppler effect = assumption? new [Re: GlennLeDrew]
      #5499996 - 11/01/12 09:46 PM

Quote:

In looking over a variety of images of the NGC7603 pair, I see no compelling reason to think the 'bridge' is nothing more than one of the larger object's spiral arms, which by chance happens to terminate at the smaller object. If such a bridge is the result of tidal stripping of stars from the interloper, there should be an 'anti-tail' of length at least some small fraction of that of the tail apparent here. If the 'bridge' is a spiral arm of the larger galaxy, it does not seem to be warped or distorted to any notable degree.

The high redshift 'knots' could well be background objects, too.




So, there is an association of two galaxies that are apparently connected by a bridge of material - but not so, because it's a chance alignment, so that material bridge is "a bridge to nowhere" like in Alaska. OK fine. But on the bridge to nowhere, there are two apparent elks dressed in extreme red, but they also are not really elks on the bridge, they are Giant Red Yetis on the distant hillside who just happen to be standing in exactly the right place so that they appear to be dead on the bridge to nowhere. So we have four complete coincidences - a bridge to nowhere (never seen), a distant hill that just happens to line up exactly with the real end of the bridge, and two distant Giant Red Yetis that just by sheer coincidence happen to appear to be standing on the bridge, even though they are 10 times farther away.

Do you now see that this is basically impossible? Thinking this way is not a defense of science - it is a refusal to accept the plain evidence of your own eyes.

-drl


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llanitedave
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Reged: 09/26/05

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Re: Red/Blue shift due to Doppler effect = assumption? new [Re: deSitter]
      #5500185 - 11/01/12 11:44 PM

Quote:

Quote:

Quote:


The problem for me is that those who are insisting that a new physics of red shift is necessary to explain these anomalies have had some 30-odd years to propose some sort of physical mechanism for it. I've yet to see one that's even serious. Surely all the creative mathematical and physics-minded folks out there haven't been idle?




Dave,

I have afew thoughts regarding this.

1. de Ruiter et al.(1998)identified an interaction between two galaxy groups with a 4000 km s-1 redshift difference between the two groups (I linked to the ADS abstract earlier in the thread and you can download the paper). There has been exactly 2 citations of this paper - both by a researcher investigating anomalous redshifts. That's it - 2 citations in the 14 years since the result was published. Do you really think that a research community so completely uninterested in a 4000 km s-1 deviation from a smooth Hubble flow is going to devote any time to developing theoretical mechanisms to explain intrinsic redshifts - even given the 40+ years since Arp's first papers on the subject?

2. Narlikar&Arp (1993) proposed a variable mass hypothesis to explain intrinsic redshifts. In this model newly created matter has lower particle masses than matter that has been in existence longer. For a long time I wondered how the particles might aquire mass in this model. The recent discovery of the Higgs Boson makes me wonder if perhaps the physics involved in the particles gaining mass in the VMH might involve some sort of interaction with the Higgs Field. But I think before we can really know we would need a better understanding of the matter creation process Arp is proposing occurs in the cores of active galaxies.

3. With an army of particle physicists and astrophysicists, we've had ~30 years of searching for the elusive CDM particle. Nothing. Clearly a 30 year time frame is not a guarantee of discovering something that is actively being sought. So why would we expect it to be enough time to develop a theoretical mechanism to explain something that almost noone thinks is happening?

Dave




My own feeling - well it's more than that, at the risk of appearing arrogant I have a worked-out field theory - is that what we are seeing is the effect of unification of gravitation and electromagnetism. From this point of view, every gravitational field also generates an electromagnetic field. For normal objects the difference in strength of 10^39 renders this moot, but for the entire universe, and for extremely condensed objects, it becomes important. Thus the whole universe carries a small temperature, which of course is the CMB. What should be looked for in these possibly intrinsically redshifted objects is line broadening coming from the fact that some regions are more redshifted than others by dint of the ambient field conditions. Seeing this would require a source of some considerable size. A typical AGN nucleus or quasar is probably not extended enough.

-drl




Danny, I'm a very long way from being qualified to give your theoretical approach any kind of critical evaluation. I can't go any further than to say I've read your paper, and my gut feeling about it is that you may indeed be on to something. And I sincerely hope that it turns out to be correct.

On the assumption that it is, doesn't it give you the ability to analyze those anomalous systems and make some testable physical predictions about them?

I definitely don't like Harp's arguments about matter having a variable mass -- if that were the case I don't think those odd galaxies would be able to form stars at all, much less populate them with familiar stellar types.

So what if you were to focus your theory on some of these discrepancies? What, exactly, would those red shifts tell us?


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deSitter
Still in Old School


Reged: 12/09/04

Re: Red/Blue shift due to Doppler effect = assumption? new [Re: llanitedave]
      #5500435 - 11/02/12 06:00 AM

Between work and other survival activities, I work on just this, and will publish when it's time The equations are beastly hard to solve and make GR look like freshman physics. But there are solutions! which is good to know.

The key problem is to set the scale of EM vs gravity from observation of the CMB. That will enable a prediction of what happens in a condensed object. That's my goal.

-drl


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GlennLeDrew
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Reged: 06/18/08

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Re: Red/Blue shift due to Doppler effect = assumption? new [Re: deSitter]
      #5500982 - 11/02/12 01:37 PM

Danny,
I fully realize that at face value three coincidental occurrences in the NGC 7603 system would be taken as a most remote possibility; they being the connecting bridge, and the two knots on that bridge.


I still see the bridge as merely a spiral arm, whose form is not so different from its counterpart on the other side of the large galaxy. If the result of an encounter between two galaxies (even when a considerable disparity in mass exists), such a neat, prominent, single, *connecting* bridge, in the absence of other more extensive tidal debris, seems just too unnatural to me.

In a Hubble image, the two 'knots' appear to me like very distant spiral systems, coincidentally superimposed on the 'bridge.' Actually, they seem to be displaced somewhat on the concave side of the bridge mid-line. If this displacement is more than just my visual impression, it must at least raise questions as to the strength of connection. Why should such well-defined concentrations not lie on the bridge mid-line if they are part of it?

As to the coincidental alignment of two distant galaxies upon the spiral arm of a foreground system. Why should this be dismissed? Could not this be one of the very few cases which statistics allows? Has anyone determined the Poission (is that the right term?) distribution on the sky of similarly redshifted objects? Can we so confidently reject out of hand such a coincidental alignment and thereby have to invoke a new Physics?

Extraordinary claims require extraordinary evidence. In this case I thus far see nothing which cannot be explained by line-of-sight projection. Ad coincidental as it undoubtedly is.


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russell23
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Reged: 05/31/09

Loc: Upstate NY
Re: Red/Blue shift due to Doppler effect = assumption? new [Re: GlennLeDrew]
      #5501224 - 11/02/12 04:43 PM

Quote:


I still see the bridge as merely a spiral arm, whose form is not so different from its counterpart on the other side of the large galaxy.




Glenn,

I hope you don't mind me jumping in again on this as I know you were replying to Danny. And let me say first that I genuinely appreciate the respectful nature of all of you engaging in this discussion. I discussed this topic at length years ago on another forum and there were a lot of rude responses. It is nice to have a reasoned discussion.

Regarding the "bridge" or "arm" that makes the apparent connection: I would say that this particular structure is rather unusual. Here is a link with one of the most detailed images of this galaxy:

http://homepage.eircom.net/~gracedieu/Observatory.htm

I don't see any obvious counter structure. If you remove this "bridge" both sides of the galaxy have a bright disk with an extended more diffuse patchy disk.

I took another look at the images of this galaxy on the IRSA Image database which compiles images from SDSS, the digitized sky survey (DSS - which includes B, R, and IR band images), and 2MASS. The "bridge" shows clearly in all SDSS and DSS images and no counter structure shows up in those images.

You can search the images here:

http://irsa.ipac.caltech.edu/applications/FinderChart/

Click "reproject" to get higher resolution images.

Quote:

If the result of an encounter between two galaxies (even when a considerable disparity in mass exists), such a neat, prominent, single, *connecting* bridge, in the absence of other more extensive tidal debris, seems just too unnatural to me.




That is why I think Arp's ejection/intrinsic redshift scenario is more plausible than tidal interaction. Obviously the chance alignment option is possible too.

Quote:

In a Hubble image, the two 'knots' appear to me like very distant spiral systems, coincidentally superimposed on the 'bridge.' Actually, they seem to be displaced somewhat on the concave side of the bridge mid-line. If this displacement is more than just my visual impression, it must at least raise questions as to the strength of connection. Why should such well-defined concentrations not lie on the bridge mid-line if they are part of it?




I don't think there is any reason they should be exactly on the mid-line. Lopez-Corredoira and Gutierrez discuss this and they are slightly off center from the mid-line. But they are clearly projected within the bridge. That doesn't prove interaction, but I think once again the arrangement is consistent with an ejection scenario and not an interloper interaction scenario.

Quote:

As to the coincidental alignment of two distant galaxies upon the spiral arm of a foreground system. Why should this be dismissed? Could not this be one of the very few cases which statistics allows? Has anyone determined the Poission (is that the right term?) distribution on the sky of similarly redshifted objects? Can we so confidently reject out of hand such a coincidental alignment and thereby have to invoke a new Physics?

Extraordinary claims require extraordinary evidence. In this case I thus far see nothing which cannot be explained by line-of-sight projection. Ad coincidental as it undoubtedly is.




It is a very coincidental alignment. The calculation actually was done. Here is the paper:

http://adsabs.harvard.edu/abs/2004A%26A...421..407L

It comes out to a 3 in a billion chance that this is an accidental arrangement. The paper also discusses the spectral characteristics of these galaxies. The are HII galaxies with spectral characteristics of dwarf galaxies.

Dave


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russell23
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Reged: 05/31/09

Loc: Upstate NY
Re: Red/Blue shift due to Doppler effect = assumption? new [Re: llanitedave]
      #5501235 - 11/02/12 04:52 PM

Quote:


I definitely don't like Harp's arguments about matter having a variable mass -- if that were the case I don't think those odd galaxies would be able to form stars at all, much less populate them with familiar stellar types.




But you really don't know until the full details of the theory and the underlying mechanism are worked out.

On page 109 of Seeing Red Arp presents a Table that provides age differences for galaxies with varying amounts of intrinsic redshift. These values are derived from the Narlikar&Arp model.

The NGC 7603 companion galaxy would be 670 million years younger than the main galaxy in this model. Of course this explanation is not without its own problems. Certainly we need to ask if the companion is less than a billion years younger then how is it the bridge is still present after billions of years of rotation.

In any case these are the sorts of details that need to be fully worked out before the idea can be disproven. We don't know that stars cannot form as newly created matter evolves and particles gain mass (again if Arp is right). I think so much of this depends upon the exact mechanism by which the initially zero-mass particles aquire mass.

Dave


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Ira
Carpal Tunnel
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Reged: 08/22/10

Loc: Mitzpe Ramon, Israel
Re: Red/Blue shift due to Doppler effect = assumption? new [Re: russell23]
      #5502381 - 11/03/12 12:58 PM

Geez, with all the image analysis SW around these days you'd think someone could do better than just eyeball a photo and give their opinion of it.

/Ira


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deSitter
Still in Old School


Reged: 12/09/04

Re: Red/Blue shift due to Doppler effect = assumption? new [Re: Ira]
      #5502434 - 11/03/12 01:45 PM

There are people over on the imaging forums who are perfectly capable of making very deep images of this galaxy to get a better view at least of the morphology.

Here's another very interesting case because there is little doubt that the two objects are adjacent - the star-forming knots are identical in size and shape:

http://en.wikipedia.org/wiki/NGC_1232

NED 1232
http://ned.ipac.caltech.edu/cgi-bin/nph-objsearch?objname=NGC+1232
Red shift distance 95 million LY

NED 1232A
http://ned.ipac.caltech.edu/cgi-bin/nph-objsearch?objname=NGC+1232A
Red shift distance 390 million LY

-drl


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deSitter
Still in Old School


Reged: 12/09/04

Re: Red/Blue shift due to Doppler effect = assumption? new [Re: deSitter]
      #5502443 - 11/03/12 01:50 PM

Idea - these spirals start out as spindles with matter spewing from one or both ends - as they evolve and spin through space the ejected material assumes a spiral pattern like a Catherine wheel firework.

-drl


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russell23
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Reged: 05/31/09

Loc: Upstate NY
Re: Red/Blue shift due to Doppler effect = assumption? new [Re: Ira]
      #5502479 - 11/03/12 02:25 PM

Quote:

Geez, with all the image analysis SW around these days you'd think someone could do better than just eyeball a photo and give their opinion of it.

/Ira




I think one thing that has happened over the years is that people have come to believe incorrectly that "eyeball" inspection of images is always inferior to computer algorithms. I've found that visually inspecting the DSS image of each galaxy in samples I've worked with makes it possible to identify galaxies with large errors in the data and reduce scatter in the analysis.

Here is one example:

http://cseligman.com/text/atlas/ngc25a.htm#2582

The galaxy in this image is NGC 2582. For galaxies an inclination of 90 degrees is edge on and an inclination of 0 degrees is face on. NGC 2582 is clearly very close to face on orientation from a visual inspection of the image. Yet several papers have published it's inclination as 51 degrees - which is incorrect and results in calculated distances that are significantly in error until a closer to face on orientation for this galaxy is applied to the data.

My point is that software has its uses, equations have their uses, but for many applications you still need to visually inspect images as a sanity check on the algorithm generated results.

I don't feel a software program is going to resolve this particular debate.

Dave


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russell23
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Reged: 05/31/09

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Re: Red/Blue shift due to Doppler effect = assumption? new [Re: deSitter]
      #5502524 - 11/03/12 02:51 PM

Quote:

There are people over on the imaging forums who are perfectly capable of making very deep images of this galaxy to get a better view at least of the morphology.

Here's another very interesting case because there is little doubt that the two objects are adjacent - the star-forming knots are identical in size and shape:

http://en.wikipedia.org/wiki/NGC_1232

NED 1232
http://ned.ipac.caltech.edu/cgi-bin/nph-objsearch?objname=NGC+1232
Red shift distance 95 million LY

NED 1232A
http://ned.ipac.caltech.edu/cgi-bin/nph-objsearch?objname=NGC+1232A
Red shift distance 390 million LY

-drl




And you can add to this analysis. The companion galaxy is NGC 1232A and is morphologically an SBm type dwarf spiral. There are 12 of these galaxies with either Cepheid distances or in the Virgo cluster and Ursa Major cluster and with measured B-band isophotal diameters. The 12 SBm galaxies in question have a typical linear diamter of 6.8 +/- 3.5 kiloparsecs (kpc) with a range of 2.7kpc to 13.1kpc.

NGC 1232A would have a linear diamter of 23.3 kpc at its Hubble distance which then is 4.7 standard deviations above the mean. NGC 1232 has a distance of 17.4 Mpc from the Tully-Fisher relation. At this distance NGC 1232A would have a diameter of 4.4 kpc which falls nicely in the range of diameters for local SBm galaxies.

The same argument can be applied to the absolute magnitude of this galaxy. At the Hubble distance the absolute magnitude of NGC 1232A is -19.72 (B-band magnitude) - which is what is expected for a moderate sized spiral of Sa, Sb, and Sc types and is much too luminous for an SBm type spiral. A the NGC 1232 Tully-Fisher distance NGC 1232A would have an absolute magnitude of -16.10 which is in the normal range for dwarf galaxies such as SBm spirals.

Dave


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Neutrino?
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Reged: 12/14/09

Loc: Wasatch Front
Re: Red/Blue shift due to Doppler effect = assumption? new [Re: deSitter]
      #5503038 - 11/03/12 09:27 PM

Quote:

Between work and other survival activities, I work on just this, and will publish when it's time The equations are beastly hard to solve and make GR look like freshman physics. But there are solutions! which is good to know.

The key problem is to set the scale of EM vs gravity from observation of the CMB. That will enable a prediction of what happens in a condensed object. That's my goal.

-drl




Where's the psuedo-Dirac eq paper? It's not available.


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deSitter
Still in Old School


Reged: 12/09/04

Re: Red/Blue shift due to Doppler effect = assumption? [Re: Neutrino?]
      #5503238 - 11/04/12 12:29 AM

It had an argument that I realized was wrong. Repairs in progress.

-drl


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deSitter
Still in Old School


Reged: 12/09/04

Re: Red/Blue shift due to Doppler effect = assumption? new [Re: russell23]
      #5503596 - 11/04/12 09:08 AM

Quote:

Quote:

There are people over on the imaging forums who are perfectly capable of making very deep images of this galaxy to get a better view at least of the morphology.

Here's another very interesting case because there is little doubt that the two objects are adjacent - the star-forming knots are identical in size and shape:

http://en.wikipedia.org/wiki/NGC_1232

NED 1232
http://ned.ipac.caltech.edu/cgi-bin/nph-objsearch?objname=NGC+1232
Red shift distance 95 million LY

NED 1232A
http://ned.ipac.caltech.edu/cgi-bin/nph-objsearch?objname=NGC+1232A
Red shift distance 390 million LY

-drl




And you can add to this analysis. The companion galaxy is NGC 1232A and is morphologically an SBm type dwarf spiral. There are 12 of these galaxies with either Cepheid distances or in the Virgo cluster and Ursa Major cluster and with measured B-band isophotal diameters. The 12 SBm galaxies in question have a typical linear diamter of 6.8 +/- 3.5 kiloparsecs (kpc) with a range of 2.7kpc to 13.1kpc.

NGC 1232A would have a linear diamter of 23.3 kpc at its Hubble distance which then is 4.7 standard deviations above the mean. NGC 1232 has a distance of 17.4 Mpc from the Tully-Fisher relation. At this distance NGC 1232A would have a diameter of 4.4 kpc which falls nicely in the range of diameters for local SBm galaxies.

The same argument can be applied to the absolute magnitude of this galaxy. At the Hubble distance the absolute magnitude of NGC 1232A is -19.72 (B-band magnitude) - which is what is expected for a moderate sized spiral of Sa, Sb, and Sc types and is much too luminous for an SBm type spiral. A the NGC 1232 Tully-Fisher distance NGC 1232A would have an absolute magnitude of -16.10 which is in the normal range for dwarf galaxies such as SBm spirals.

Dave




Yes, very excellent point.

Here's a larger image - look below the galaxy - there are strange red spindles everywhere, some well defined, some just emerging. There is one embedded in the galaxy itself at about the 2-o'clock position, coincident with a thick dust lane. There are several dwarfs to the left which are of the spindle type with one small tendril emerging from either end. One always sees these spindles in the vicinity of active galaxies.

http://www.robgendlerastropics.com/NGC1232-Subaru-ESO-L.jpg

-drl


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BillFerris
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Reged: 07/17/04

Loc: Flagstaff, Arizona, USA
Re: Red/Blue shift due to Doppler effect = assumption? new [Re: russell23]
      #5503717 - 11/04/12 10:45 AM

As points of reference, in his 1988 publication, Nearby Galaxies Catalog, Tully includes distances of 20.0 megaparsecs (Mpc) and 21.1 megasparsecs, respectively, for NGC 1232 and NGC 1232A. The respective distance modulus data for these galaxies are 31.50 Mpc (N1232) and 31.62 Mpc (N1232A).

Bill in Flag


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