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llanitedave
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Re: Red/Blue shift due to Doppler effect = assumption? new [Re: deSitter]
      #5497030 - 10/30/12 10:44 PM

I would think the simplest possibility is the one that doesn't require a whole new physics to explain.

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russell23
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Re: Red/Blue shift due to Doppler effect = assumption? new [Re: GlennLeDrew]
      #5497044 - 10/30/12 10:55 PM

Quote:

I would be most cautious of interpreting 'connecting bridges' based on appearance alone. There must be more robust evidence to confirm that they result from more than chance superposition. One effect to be aware of is that subtle features can be made more apparent when seen against another smooth source. An example is the M110's tidal tail, being more apparent where seen against the faint, smooth glow in the outer parts of M31. Someone not acquainted with tidal effects might interpret this as a connecting bridge. Of course, we know with some confidence that M31 and M110 are effectively interacting. But suppose M110 was a very much more distant object having the same tidal tail-like extension; it might initially give the impression of a 'connection' to the foreground M31.




Glenn,

The research literature is littered with discussion of luminous bridges and filaments indicating interaction between two galaxies. A bridge is a standard form of evidence for interaction. The only distinction between NGC 7603/NGC 7603B and the numerous accepted bridged interactions is the redshift differential.

Even on the SDSS SkyServer NGC 7603/NGC 7603B is listed as an interacting pair:

http://skyserver.sdss.org/edr/en/tools/places/page5.asp

This is a classic case where a definitive test could be made if researchers would get the required data. As an early type galaxy NGC 7603B could have its distance determined via the Surface Brightness Fluctuation Method. But that would require somebody choose to take the risk of ridicule that might come their way if the SBF distance of NGC 7603B turned out to be the same as NGC 7603. It's safer just to avoid that possibility altogether.

But the reality is that the bridge itself is evidence for interaction. Any image of this system I've ever seen shows the bridge terminating precisely at NGC 7603B. A bridge of this type is generated by interaction. If the interacting companion is not NGC 7603B, then what object is responsible for the bridge?

Note that I am not saying the bridge is proof of interaction. I'm saying it is evidence for interaction. The only tests that would prove interaction would be reliable redshift independent distance estimates for both NGC 7603 and NGC 7603B. The existence of the bridge is enough evidence to justify further investigation of the redshift anomoly of this system.


Dave


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russell23
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Re: Red/Blue shift due to Doppler effect = assumption? new [Re: deSitter]
      #5497058 - 10/30/12 11:08 PM

Quote:

Great post. It's very important to understand that the Hubble relation is real. I am convinced that some redshifts are intrinsic, but they appear, as you say, superposed on the Hubble effect.




Right, In an intrinsic redshift model there is an underlying redshift-distance relation defined by some value of the Hubble constant upon which intrinsic redshifts would be superposed. For normal galaxies the intrinsic redshifts would be small. For quasars the intrinsic redshifts would be very large.

Quote:

Too often "Arpists" are stridently against any redshift that has cosmic interpretations,




It is often the case that those who read and become enamored by Arp's work fail to recognize that Arp himself thinks there is an underlying redshift-distance relation defined by a Hubble Constant of 55 km s-1 Mpc-1. For normal galaxies the observed redshift velocity would be comprised of 3 components:

Vobs = H0r + Vpec + Vint

Where Vobs is the observed redshift velocity; H0r is the Hubble constant x the distance (r); Vpec is a peculiar velocity component; and Vint is the intrinsic redshift component.

The problem is you can't really identify intrinsic redshifts that are small as intrinsic redshifts because they are too easily interpreted as peculiar motions. You need to identify instances where the observations indicate the galaxy would have a redshift deviation too large to be a peculiar motion - such as in NGC 7603B.


Quote:

while those who denigrate them often appear to be unwilling to even look with an open mind. Sounds like politics no?




Well, the problem is with the wealth of different things that could be studied almost nobody is interested in looking into the redshift anomalies for fear of being labeled a quack. That doesn't exactly sound like a promising direction for a young researcher looking to establish their reputation. Unfortunately, a system that declares viable scientific possibilities as off-limits for study actually slows the progress of science.

Dave

-drl




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russell23
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Re: Red/Blue shift due to Doppler effect = assumption? new [Re: llanitedave]
      #5497070 - 10/30/12 11:23 PM

Quote:

I would think the simplest possibility is the one that doesn't require a whole new physics to explain.




Simplicity is a terrible criteria for judging the fitness of a hypothesis, theory, or interpretation of the data. Observational evidence is how scientific ideas are tested.

Simplicity is no longer relevant when you get to the point of distinguishing published ideas. Simplicity is utilized in developing an idea in the first place. Once developed and put forward to challenge a different theory the evidence is the deciding factor.

If we take NGC 7603/NGC 7603B as an example ... all that is needed is someone to get a SBF distance to NGC 7603B and perhaps the same method could be used on NGC 7603 if the nuclear/bulge region was studied since the SBF method is better applied to early type galaxies. If the two galaxies have the same SBF distance within the uncertainty of the measurements and calibration then you've established that large redshift anomalies are real in some objects. If the SBF distances do not agree, then you've dealt a significant blow to the Arp model. That is how science is supposed to work. Simplicity has nothing to do with it. If the SBF distances of NGC 7603 and NGC 7603B are the same you're going to need new physics whether that makes things less simple or not.

The "new physics" with regards to Arp is just much about nothing. Dark energy is new physics. I don't here anyone in the mainstream astrophysics research community objecting to dark energy on the grounds that it requires new physics.

On a more philosophical note I have to wonder why anyone would object to observations/interpretations that imply we might need some new physics. Isn't that how science advances? Does anybody actual think after looking at the scientific advances of the last 100 years that it is preposterous that the future will not bring about new physics?

Dave


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Kobayashi
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Re: Red/Blue shift due to Doppler effect = assumption? new [Re: russell23]
      #5497094 - 10/30/12 11:52 PM

Quote:

On a more philosophical note I have to wonder why anyone would object to observations/interpretations that imply we might need some new physics. Isn't that how science advances?




Science advances when we find observations and data that cannot be explained by our existing, established theories. Looking for alternate explanations for observations that we can already explain is not science, it's fantasy or fiction.


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Rick Woods
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Re: Red/Blue shift due to Doppler effect = assumption? new [Re: Kobayashi]
      #5497157 - 10/31/12 12:36 AM

Quote:

Quote:

On a more philosophical note I have to wonder why anyone would object to observations/interpretations that imply we might need some new physics. Isn't that how science advances?




Science advances when we find observations and data that cannot be explained by our existing, established theories. Looking for alternate explanations for observations that we can already explain is not science, it's fantasy or fiction.




Not necessarily. Epicycles explained planetary motions to the satisfaction of the scientific community of the day. Aristotle was the last word in science for centuries, until people began thinking for themselves and looking at things in different ways.

There's nothing sacred about existing, established theories. They're still just theories. If someone doesn't like them, that's when a better one gets developed. (Or a worse one, which then gets shot full of holes and discarded. That's how science advances.)


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Kobayashi
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Re: Red/Blue shift due to Doppler effect = assumption? new [Re: Rick Woods]
      #5497198 - 10/31/12 01:23 AM

Quote:

Epicycles explained planetary motions to the satisfaction of the scientific community of the day.




And it wasn't rejected until higher accuracy observations were made, and the discrepancy between prediction and observation became clear.

Quote:

There's nothing sacred about existing, established theories. They're still just theories. If someone doesn't like them, that's when a better one gets developed.




"Just a theory" is a phrase that demonstrates profound misunderstanding of what a scientific theory is. A scientific theory is not a mere hypothesis; it's an explanation of the world that has been thoroughly confirmed by observations and experimentation (cite). You don't throw it away without very good reason.


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deSitter
Still in Old School


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Re: Red/Blue shift due to Doppler effect = assumption? new [Re: russell23]
      #5497289 - 10/31/12 04:51 AM

Quote:

Quote:

I would think the simplest possibility is the one that doesn't require a whole new physics to explain.




Simplicity is a terrible criteria for judging the fitness of a hypothesis, theory, or interpretation of the data. Observational evidence is how scientific ideas are tested.

Simplicity is no longer relevant when you get to the point of distinguishing published ideas. Simplicity is utilized in developing an idea in the first place. Once developed and put forward to challenge a different theory the evidence is the deciding factor.

If we take NGC 7603/NGC 7603B as an example ... all that is needed is someone to get a SBF distance to NGC 7603B and perhaps the same method could be used on NGC 7603 if the nuclear/bulge region was studied since the SBF method is better applied to early type galaxies. If the two galaxies have the same SBF distance within the uncertainty of the measurements and calibration then you've established that large redshift anomalies are real in some objects. If the SBF distances do not agree, then you've dealt a significant blow to the Arp model. That is how science is supposed to work. Simplicity has nothing to do with it. If the SBF distances of NGC 7603 and NGC 7603B are the same you're going to need new physics whether that makes things less simple or not.

The "new physics" with regards to Arp is just much about nothing. Dark energy is new physics. I don't here anyone in the mainstream astrophysics research community objecting to dark energy on the grounds that it requires new physics.

On a more philosophical note I have to wonder why anyone would object to observations/interpretations that imply we might need some new physics. Isn't that how science advances? Does anybody actual think after looking at the scientific advances of the last 100 years that it is preposterous that the future will not bring about new physics?

Dave




While it is stated in the papers of Lopez-C, we should for thread purposes mention that the bridge between 7603/B also contains two small knots which themselves have extremely anomalous redshifts, see here:

http://quasars.org/ngc7603.htm

-drl


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russell23
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Re: Red/Blue shift due to Doppler effect = assumption? new [Re: Kobayashi]
      #5497431 - 10/31/12 08:48 AM

Quote:

Quote:

On a more philosophical note I have to wonder why anyone would object to observations/interpretations that imply we might need some new physics. Isn't that how science advances?




Science advances when we find observations and data that cannot be explained by our existing, established theories.




Yes - like two objects apparently connected by a bridge of luminous material that have an 8000 km s-1 difference in redshift.

Quote:

Looking for alternate explanations for observations that we can already explain is not science, it's fantasy or fiction.




Two things - First, that is not the situation we are discussing. NGC 7603/NGC 7603B is an anomalous redshift pairing that is not explained by standard theories if the two objects are in fact interacting as the luminous bridge would indicate.

Second, There is no rule in science that an alternate theory cannot be brought forward to explain observations that are already explained. The key component of an alternate theory would be that it would need to explain things that the standard theory is incapable of explaining or make predictions different in some aspects from the standard theory.

Dave


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deSitter
Still in Old School


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Re: Red/Blue shift due to Doppler effect = assumption? new [Re: russell23]
      #5497438 - 10/31/12 08:54 AM

Quote:


Second, There is no rule in science that an alternate theory cannot be brought forward to explain observations that are already explained. The key component of an alternate theory would be that it would need to explain things that the standard theory is incapable of explaining or make predictions different in some aspects from the standard theory.

Dave




Exactly, this is how things always move forward, without exception. In the case of GR, a residual error of 0.012 degree per century in the orbit of Mercury was sufficient cause to re-explain the already explained, the idea of Newton's central force and action at a distance.

-drl


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russell23
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Re: Red/Blue shift due to Doppler effect = assumption? new [Re: deSitter]
      #5497439 - 10/31/12 08:54 AM

Quote:

Quote:

Quote:

I would think the simplest possibility is the one that doesn't require a whole new physics to explain.




Simplicity is a terrible criteria for judging the fitness of a hypothesis, theory, or interpretation of the data. Observational evidence is how scientific ideas are tested.

Simplicity is no longer relevant when you get to the point of distinguishing published ideas. Simplicity is utilized in developing an idea in the first place. Once developed and put forward to challenge a different theory the evidence is the deciding factor.

If we take NGC 7603/NGC 7603B as an example ... all that is needed is someone to get a SBF distance to NGC 7603B and perhaps the same method could be used on NGC 7603 if the nuclear/bulge region was studied since the SBF method is better applied to early type galaxies. If the two galaxies have the same SBF distance within the uncertainty of the measurements and calibration then you've established that large redshift anomalies are real in some objects. If the SBF distances do not agree, then you've dealt a significant blow to the Arp model. That is how science is supposed to work. Simplicity has nothing to do with it. If the SBF distances of NGC 7603 and NGC 7603B are the same you're going to need new physics whether that makes things less simple or not.

The "new physics" with regards to Arp is just much about nothing. Dark energy is new physics. I don't here anyone in the mainstream astrophysics research community objecting to dark energy on the grounds that it requires new physics.

On a more philosophical note I have to wonder why anyone would object to observations/interpretations that imply we might need some new physics. Isn't that how science advances? Does anybody actual think after looking at the scientific advances of the last 100 years that it is preposterous that the future will not bring about new physics?

Dave




While it is stated in the papers of Lopez-C, we should for thread purposes mention that the bridge between 7603/B also contains two small knots which themselves have extremely anomalous redshifts, see here:

http://quasars.org/ngc7603.htm

-drl




Yes - the HII galaxies in the filament are another aspect of this system. To me the big problem with them is that there is no obvious means to establish that they are in fact interacting with the filament.

This has always been the problem with Arp's local quasars model. The whole thing gets bogged down in statistics because there are no redshift independent distance estimates for quasars. While Arp's first anomalous redshift evidence involved quasars, I think ultimately the way to get there is a more bottom up approach. Convincing evidence needs to be brought forward establishing that normal galaxies have anomalous redshift deviations too large to be accounted for by peculiar motions - something Arp has also argued. Statistical arguments just don't resolve the issue because no matter how low the probability of a chance alignment it can always be argued that it is still an accidental alignment ... or even the statistical analysis can be endlessly debated. This is in fact what has gone on with Arp's ideas for decades.

Dave


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Pess
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Re: Red/Blue shift due to Doppler effect = assumption? new [Re: deSitter]
      #5497531 - 10/31/12 10:15 AM

Quote:


The problem is really the timescales involved in detecting a change in redshift. As part of a paper I just submitted I listed the observed redshift values of the galaxy being discussed and the measured redshift values had a range of 110 km s-1. With a Hubble constant of 70 km s-1 Mpc-1 that is equivalent to a distance of ~1.5 Megaparsecs. Note the galaxy has not actually moved 1.5 Mpc in the 20 years of measurements the data covers. That is just the range of redshift values provided by different instruments. So the uncertainty in our redshift measurements will swamp out any changes in expansion redshifts over any timescales realistic for us to conduct measurements.

Dave




That's pretty much my thought on just figuring it out on scratch paper.

The further an object is away from us the faster it is receding and so the less time needed to detect it.

I think the problem is two-fold. Timescale for detection & sensitivity of detecting instruments.

Obviously a large number of distant (extragalactic) objects would be observed over a long period of time to provide a definite answer.

Quasars, AGN's and anything else we can viably measure so the results are not object-target specific.

Obviously this experiment would depend on the sensitivity of the measurements. I suspect if we could double our present instrument sensitivity we could find an answer in a minimum of about 50 years of observation.

Pesse (I'll haul my Meade 2.0" Refractor out tonight and start measuring!) Mist


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Pess
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Re: Red/Blue shift due to Doppler effect = assumption? new [Re: Pess]
      #5497588 - 10/31/12 11:04 AM

Quote:

On a more philosophical note I have to wonder why anyone would object to observations/interpretations that imply we might need some new physics. Isn't that how science advances? Does anybody actual think after looking at the scientific advances of the last 100 years that it is preposterous that the future will not bring about new physics?

Dave




I have felt for a long time that we are just on the verge of something new. Like Einstein flipped the world with his realization about the nature of light.

The Standard Model is a complex particle zoo that begs for a simpler underpinning.

We can describe gravity but can't really explain it.

Einstein came up with some new ideas that greatly simplified things compared to previous models..just as Copernicanism simplified astronomy even though Ptolemy epicycles already explained things (albeit in a very complicated and not particularly satisfying way).

In short, we got a long way to go before we understand physics completely.

Pesse (Heck, we can't even figure out what's going on in a bottle of powdered Palladium & water when a current is run through it!) Mist


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GlennLeDrew
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Re: Red/Blue shift due to Doppler effect = assumption? new [Re: Pess]
      #5498271 - 10/31/12 06:59 PM

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.


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russell23
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Re: Red/Blue shift due to Doppler effect = assumption? new [Re: GlennLeDrew]
      #5498572 - 10/31/12 10:15 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.




If the two objects are interacting and at the same distance then the problem is a gravitational interaction scenario is simply not going to be able to explain an 8000 km s-1 redshift difference. Instead what is proposed for systems like this is that the lower redshift object - which in this case is an active Seyfert galaxy - has ejected the higher redshift object from its core. In an ejection scenario there is no counter tail to the ejection. The filament we see between NGC 7603 and NGC 7603B is matter entrained in the outward movement of the ejected object.

Here is what the SDSS SkyServer has to say about this pair:

Quote:

NGC 7603/ PGC 07041, an interacting pair. Notice the bridge between the two galaxies. The bigger object, NGC 7603, is a well-known Seyfert galaxy. These are known for their very small and bright core.




http://skyserver.sdss.org/edr/en/tools/places/page5.asp

Quote:

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




Yes they could be. As could NGC 7603B. The difference is that NGC 7603B provides the possibility of a redshift independent distance estimate since it is a normal looking early type galaxy.

Dave


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llanitedave
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Re: Red/Blue shift due to Doppler effect = assumption? new [Re: russell23]
      #5498652 - 10/31/12 11:02 PM

Quote:

Quote:

Quote:

On a more philosophical note I have to wonder why anyone would object to observations/interpretations that imply we might need some new physics. Isn't that how science advances?




Science advances when we find observations and data that cannot be explained by our existing, established theories.




Yes - like two objects apparently connected by a bridge of luminous material that have an 8000 km s-1 difference in redshift.

Quote:

Looking for alternate explanations for observations that we can already explain is not science, it's fantasy or fiction.




Two things - First, that is not the situation we are discussing. NGC 7603/NGC 7603B is an anomalous redshift pairing that is not explained by standard theories if the two objects are in fact interacting as the luminous bridge would indicate.

Second, There is no rule in science that an alternate theory cannot be brought forward to explain observations that are already explained. The key component of an alternate theory would be that it would need to explain things that the standard theory is incapable of explaining or make predictions different in some aspects from the standard theory.

Dave




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?


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Ira
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Re: Red/Blue shift due to Doppler effect = assumption? new [Re: llanitedave]
      #5498676 - 10/31/12 11:19 PM

We can PROVE that objects in motion undergo a doppler shift. It's easy for sound. I assume it is also demonstrable for light. (I say "assume" just because I can't cite the chapter and verse for those experiments.) Therefore, isn't it more the case that you must prove that red/blue shifts aren't the results of doppler shift rather than having to prove that they are?

/Ira


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russell23
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Re: Red/Blue shift due to Doppler effect = assumption? new [Re: llanitedave]
      #5498974 - 11/01/12 07:24 AM

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


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russell23
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Re: Red/Blue shift due to Doppler effect = assumption? new [Re: Ira]
      #5498982 - 11/01/12 07:36 AM

Quote:

We can PROVE that objects in motion undergo a doppler shift. It's easy for sound. I assume it is also demonstrable for light. (I say "assume" just because I can't cite the chapter and verse for those experiments.) Therefore, isn't it more the case that you must prove that red/blue shifts aren't the results of doppler shift rather than having to prove that they are?

/Ira




Ira,

The situation is far more complicated than that. And really unless a person becomes very familiar with Arp's writing it is easy to misunderstand what is being claimed.

Arp does not deny the existence of doppler shifting as a factor affecting observed redshifts. For example, as I mentioned (and linked to earlier) spiral galaxy rotational velocities are measured by observing the doppler shifting that occurs across the disk of a galaxy. The side rotating toward our line of sight is blueshift relative to the nucleus and the side rotating away from our line of sight is redshifted relative to the nucleus.

Second, Arp in 1980 - and later papers- argued for instances where the redshifts of pairs of quasars he claimed are ejected from an active galaxy show doppler shifting relative to quantized peaks (see Arp&Hazard 1980). So he interpreted the redshift of the quasars as being mostly intrinsic, with a smaller doppler component superposed on the pair as one QSO was ejected toward us and the other was ejected away from us at ejection velocities of ~10000 km s-1 (which subsequently have turned out to be the approximate velocities that matter is often found moving outward from the "supermassive black holes" that supposedly reside in AGN).

Third, Arp does think that there is an underlying velocity-distance relationship that contributes a component of the redshift to all objects and is of the order described by a Hubble Constant of ~55-60 km s-1 Mpc-1.

Fourth - It is really about finding a mechansism that is capable of explaining intrinsic redshifts - not disproving other mechanisms. The mechanism would have to explain intrinsic redshifts in normal galaxies on the order of a few thousands of km s-1 on up through a dominant intrinsic redshift in quasars if Arp is correct that they are local.

Dave


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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]
      #5499041 - 11/01/12 09:03 AM

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


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