Here's a link to a paper from Halton Arp et al. about the 'periodicity' of quasar redshifts taken from 2dF and SDSS surveys.
Periodicities of Quasar Redshifts in Large Area Surveys

Personally, I don't think he made a strong case for what he's claiming, but as you know I think his whole line of reasoning about quasars is wrong.

__________________
Forming opinions as we speak

Their hypotesis is in agreement with the theory of interaction. But what is the cause of
ejection. Are these galaxies disturbed by recent collisions with other galaxies?

Arp et al. say they are simply ejected from 'active galactic nuclei'. They do not give a cause, or make a claim as to what makes a galactic nucleus 'active'. As I've said before, main stream astronomers have many good observations strongly suggesting that quasars are extremely active galactic nuclei themselves, and are at cosmological distances. Arp's model contains many self-contradictions, and claims that are repudiated by observation.

__________________
Forming opinions as we speak

Really? Could you name some of them?

Cheers.

I assume that you mean "could I list some of them", as these are not the sort of things thaqt acquire names.

For starters there is the fact that quasars ar seen to be in the center of galaxies with redshifts exactly matching the galaxy, yet Arp et. al say that quasars are emitted from galaxies and have an intrinsic redshift vastly different from the "host galaxy".

Arp ignores quasars with observed host galaxies, because they do not fit his outside-the-box model.

__________________
Forming opinions as we speak

Another is his contention that "many" quasars are seen to be aligned with low redshift galaxies. A silly comment because there are literally billions of galaxies, so of course some will appear to be aligned with distant quasars. Further while "many" might like that way, "most" do not.

Arp's biggest failing, IMHO, is his reliance on 2-dimensional images to support a premise requiring three dimensions. He can say "it looks like" all he wants, but it does not change the fact that he has no other objective evidence to support his contention.

__________________
All civilizations become either spacefaring or extinct.~ Carl Sagan ~

Humanity must rise above the Earth, to the top of the atmosphere and beyond, for only then will we fully understand the world in which we live.~Socrates, 500 B.C. ~

Let every man judge according to his own standards, by what he has himself read, not by what others tell him. ~Albert Einstein~

That's a common misconception. See here:

http://adsabs.harvard.edu/cgi-bin/nph-bib_...417276a6f017562

Arp contends that quasars evolve into normal galaxies. The quasar is the nucleus of this evolving galaxy in his model just as in the standard model. Seeing surrounding galaxy structure is expected. He's not ignoring it.

__________________
"The scientist who asks the right question reconnoiters a new patch of the unknown, and may, with luck, bring it within the constricted but expanding boundaries of the known."

~Timothy Ferris (The Red Limit) 1982

This is another common misconception. First, Arp is arguing that quasars are intrinsically low luminosity which means that most of the observed quasars must be local (within 100 Mpc - at least prior to surveys like SDSS) in his model. So you don't have billions of galaxies to choose from. You have the local sample.

Second, Arp model makes a very specific prediction - active galaxies such as Seyferts and starbursts should dominate the population of low redshift parent galaxies associated with ejected quasars - and that's what his results show. If you read his papers you find that the vast majority of his examples involve active galaxies.

The mainstream suffers from the opposite failing of what you're accusing Arp of - relying on a assumption (redshift = distance) that creates a 3-dimensional interpretation which may in fact be contradicted by the observations.

__________________
"The scientist who asks the right question reconnoiters a new patch of the unknown, and may, with luck, bring it within the constricted but expanding boundaries of the known."

~Timothy Ferris (The Red Limit) 1982

"Arp contends that quasars evolve into normal galaxies. The quasar is the nucleus of this evolving galaxy in his model just as in the standard model. Seeing surrounding galaxy structure is expected. He's not ignoring it."

It very interesting how Arp and Savov come to similar models while walking in qualitatively different parts. There is has to something much more deep here than pure game of chance.

First, there are no observations that contradict the correlation between redshift and distance.

Second, I assume that in this case you are referring only to quasars, and not to galaxies, when you suggest that there is some discrepency between redshift and distance. Quasars being Arp's biggest obvious difference from main-stream astronomers. Certainly there is very consistent and powerful evidence that galaxies have a very tight correlation between redshift and distance. This includes the galaxies that host quasars, such as 3C273.

So, the redshift=distance assumption [as you call it] is well tested and very reliable. This is very different from Arp's [it looks like...] assumptions.

__________________
Forming opinions as we speak

No, this is a common failing of Arp and those who support him. It is the argument of intrinsically low luminosity that is not supported by any of his research to date. These also leads to a failure in logic. Arp contends that QSO's show low luminousity, then shows two-dimensional images which he contends show association between QSO's and low reshift galaxies, then says see, this is why the QSO'as are low luminousity. (Josh, in the EU thread, gave a latin saying for this which fits perfectly) Arp is using his premise to arrive at a conclusion when the premise itself is the thing which is being argued.

Yes, but the "vast majority" of his models are based on a very small sampling of the objects in the sky. Furthermore, he does not address many more objects that do not show the association he claims for those objects he does include. Finally, the association he makes is still based on his initial premise, taken as true, that there is an association--a premise that he has not provided convincing evidence to support.

Except that the "mainstream" as you put it, have shown convincing evidence that the redshift = distance correlation is strong. While it does remain a theory, in that the objects discussed are too far away to get a parallax measurement to prove it, the series of "standard candles" used by astronomers to get out to several hundreds of millions of light years do support the redshift contention out to that distance. Arp has no such quantifying support for his theory.

__________________
All civilizations become either spacefaring or extinct.~ Carl Sagan ~

Humanity must rise above the Earth, to the top of the atmosphere and beyond, for only then will we fully understand the world in which we live.~Socrates, 500 B.C. ~

Let every man judge according to his own standards, by what he has himself read, not by what others tell him. ~Albert Einstein~

Sorry, as I explained earlier, English is not my native language.

There is no contradiction in Arp's model.


In Arp's model quasars evolve into galaxies, where is the problem with host galaxies?

Wrong, the quasars are aligned across a specific type of galaxy (Seyfert/disturbed galaxies), you don't seem to know what the model is about apparently.

We would all like to have more 3-D information, but Arp's model does not rely on 2-D images where did you get that idea? The distances to the parent galaxy of the individual quasars of a quasar pair can show if the axis of alignment is offset, I suggest you read more of his work.

Again, read his work,

have fun.

I have changed the post.
It is difficult to not be dismissive of Arp's model.
I have read a represntative sample. I am entertained by his methods and disagree strongly with his conclusions.

__________________
Forming opinions as we speak

Get over it. I agree with Antoniseb on this--Arp's model is silly to those who take the time to review it in detail. The quantification fits, it is not a personal attack, and it's inclusion in the sentence states an opinion.

It is also my opinion that the theory is a load of bunkum, and is beyond silly.

Ok, pay attention here. Arp says that QSO's are close, display low luminosity, and are ejected by nearby active galaxies. Images of QSO's with their actual associated galaxies show equal redshifts between the QSO and the associated galaxy, none of which are close. Now, does that make the problem obvious, or should I add more to help make it clearer?

See VanderL, this is a personal shot, and I take exception to it. You and I, with a host of others of course, have been discussing Arp's silly model for months now. Do you really think I haven't read the drivel he puts out to support it?

Not to make to fine a point on it, but you are wrong. Arp's only support are 2d images he has obtained, which he says show an association. There is no other quantitative support for his model

If there is VanderL, please point it out to me.

__________________
All civilizations become either spacefaring or extinct.~ Carl Sagan ~

Humanity must rise above the Earth, to the top of the atmosphere and beyond, for only then will we fully understand the world in which we live.~Socrates, 500 B.C. ~

Let every man judge according to his own standards, by what he has himself read, not by what others tell him. ~Albert Einstein~

No, that's an improper characterization. Arp did not start with the premise that quasars are low intrinsic luminosity. That is an implication of his model. If they're nearby, then given their observed magnitudes - they're low luminosity.

__________________
"The scientist who asks the right question reconnoiters a new patch of the unknown, and may, with luck, bring it within the constricted but expanding boundaries of the known."

~Timothy Ferris (The Red Limit) 1982

I can't help you if you look at examples like NGC 7603 and NEQ3 and then claim that there is no convincing evidence that he's provided a scientifically viable scenario. Arp's been accused of falling into a trap of letting his eyes deceive him. It seems to me that in some cases, the mainstream position is allowing its theoretical expectations to deceive it. Intellectual self deception is no less plausible than sensory self deception.

__________________
"The scientist who asks the right question reconnoiters a new patch of the unknown, and may, with luck, bring it within the constricted but expanding boundaries of the known."

~Timothy Ferris (The Red Limit) 1982

Thanks, much appreciated.

Cheers.

How else can I put this, except to say that you are dead wrong. Arp was imaging QSO's and noted a couple of them "seemed" to be associated with nearer (not nearby, btw) galaxies. He then went looking specifically for other images which he felt might also show an association.

So, he saw something he thought was odd, proposed a theory for the oddness, then set out to find examples of the theory he composed. In the process, he ignored several other lines of research which added weight to the redshift = distance theory, and has provided no evidence excepting images since.

I agree, if the objects are nearby, they are low luminosity. I do not agree, however, that they are nearby and I find the evidence of such an association as provided by Arp wholly unconvincing.

__________________
All civilizations become either spacefaring or extinct.~ Carl Sagan ~

Humanity must rise above the Earth, to the top of the atmosphere and beyond, for only then will we fully understand the world in which we live.~Socrates, 500 B.C. ~

Let every man judge according to his own standards, by what he has himself read, not by what others tell him. ~Albert Einstein~

I did, and I don't know what you are saying.

Cheers.