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Thread: More from Arp et al.

  1. #1351
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    Quote Originally Posted by antoniseb
    I don't think that Arp's team has said anything about why most quasars do not exhibit bridges, and why a few may show bridges, but I've assumed they think that bridges happen in flukey situations.
    I don't think it can be said that bridges are not present in the quasar situation. For example in this paper neutral hydrogen and x-rays show a bridge to several of the quasars. This is not the only example.

    So the problem may not be a lack of bridges - but a lack of aquired data capable of determining the presence or absence of bridges.

    On the other hand - given that Arp's scenario involves ejection of quasars along the minor axis - there is reason for expecting very little interaction of ejected QSO's with the disk of the galaxy in minor axis ejections and so the optical bridges that we see with the M-51 types should be much less frequently observed.

  2. #1352
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    Quote Originally Posted by antoniseb
    I don't think that Arp's team has said anything about why most quasars do not exhibit bridges, and why a few may show bridges, but I've assumed they think that bridges happen in flukey situations.
    This is a good, and interesting argument. I meant to answer this before, but I forgot (there was so much going on in this thread).

    First issue is the brightness of the ejected material. Arp says that newly created quasars are faint, and they grow in brightness as they age. There are also large velocities involved in the ejection. So we might expect that when the high redshift, newly created quasar is still close to the parent galaxy, the new matter of the quasar is still quite faint, and if there's a bridge made of that newly created matter, it might be too dim for us to see. Perhaps the bridge might show up on radio frequencies, as in the case of 3C 343.1 (or in X-ray frequencies as dgruss23 pointed out while I was writing this post).

    But perhaps we might expect some bridges between quasars and galaxies that are made of the material dragged out of the parent galaxy, so that it should be luminous enough for us to see it. But in Narlikar-Arp variable mass theory newly created matter has very low mass, so perhaps ejected quasars have so low mass that they are not able to drag enough material from the parent galaxy to make much of a bridge.

    In the light of what I said above, I think that these bridges we see are not bridges created during an ejection event, instead I think that they are formed when the ejected objects return to the vicinity of the parent galaxy. So I think that the bridges are due to galaxies interacting with each other, only that the other one of the two galaxies (the ejected quasar has evolved to a galaxy) is younger and therefore more redshifted.

  3. #1353
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    Quote Originally Posted by antoniseb
    Basically we are looking at alleged bridges from active galaxies to quasars as fit Arp's ideas.
    I'm curious if there is anybody out there planning on adding additional commentary on this topic. There were some interesting examples I noted that have not yet been commented on. For example, there was the case of the B2 1629+37 radio galaxy with a 4100 km s-1 redshift differential.

  4. #1354
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    Quote Originally Posted by turbo-1
    Do the supporters of concordance cosmology have an explanation for the observation that the smaller galaxies of the bridged pairs are routinely redshifted WRT the hosts? If not, can we agree that this is strong evidence for intrinsic redshift?
    Well, looked at from the other direction, according to your figures....

    Quote Originally Posted by turbo-1
    Of the 41 systems for which a differential velocity can be determined, 6 (15%) are listed with 0 differential, 24 (59%) are listed with the smaller companion having the higher redshift, and 9 (22%) are listed with the host being more redshifted than the companion.
    ....15 out of the 6+24+9=39 cases, or 38%, are cases where the smaller companion does NOT have a higher redshift. So out of a sample size of ~40, no, this does not seem to be particularly strong evidence for intrinsic redshift.
    Everyone is entitled to his own opinion, but not his own facts.

  5. #1355
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    Quote Originally Posted by Cougar
    ....15 out of the 6+24+9=39 cases, or 38%, are cases where the smaller companion does NOT have a higher redshift. So out of a sample size of ~40, no, this does not seem to be particularly strong evidence for intrinsic redshift.
    Hi turbo-1,
    Could you summarize for us again your findings. In post # 1348 you stated that 100% of the cases showed the smaller companion was positively redshifted wrt the larger, for differential velocities down to 275 km/sec. How does that data set differ from the one Cougar summarized above. Thanks for a clarification on this.
    TomT
    edited: changed 250 to 275.

  6. #1356
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    Quote Originally Posted by Cougar
    ....15 out of the 6+24+9=39 cases, or 38%, are cases where the smaller companion does NOT have a higher redshift. So out of a sample size of ~40, no, this does not seem to be particularly strong evidence for intrinsic redshift.
    Thanks for adding up the three groups (39 instead of 41). I wrote that summary before determining two more redshifts - one 0 and one negative. I have edited section b. to reflect that. I should have proof-read every thing just ONE more time before posting. The percentages didn't change much, though.

    As it stands, the larger galaxy is redshifted more than the companion only 10 times out of 41 AND those differentials are all very small - well within the range of ejection velocities of small to medium sized galaxies (<275 km/s to be precise). In over twice as many bridged associations (24), the the smaller companion has the excess and the magnitude of that redshift differential is much larger on average than the group of 10. 2643 km/s differential vs -77 km/s. Even if we kick out AM 2052-221's very high redshift differential, the average differential of the remaining 23 is still 1170 km/s - over 15x the differential in the group containing the redshifted hosts.

    The sample size is not very large, but even if NED had sufficient spectral info to determine the differentials of the remaining 77 Arp an A-M bridged pairs, I doubt that the relationship would change. If the bridges are real, these stats provide solid evidence that astronomical objects can exhibit intrinsic redshift. As far as I can determine, the only reason that the bridges are not considered real is that the bridged objects have different redshifts. Considering NGC 7603 as our poster child for this argument, there seems no other reason that the reality of the bridge can be denied - there are far too many aspects of the system that support interaction.

  7. #1357
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    Quote Originally Posted by TomT
    Hi turbo-1,
    Could you summarize for us again your findings. In post # 1348 you stated that 100% of the cases showed the smaller companion was positively redshifted wrt the larger, for differential velocities down to 275 km/sec. How does that data set differ from the one Cougar summarized above. Thanks for a clarification on this.
    TomT
    edited: changed 250 to 275.
    It's the same data set. I inadvertently left out one 0 differential and one negative differential system, bringing the total number of systems to 41. No excuse for the sloppiness, except that I was working with a variety of media and didn't proof the post very well. I was just excited to bring this info to the thread.

    And yes, Cougar initially suggested that if the redshift differential was on the order of 1000 km/s, he would not consider the galaxies to be interacting with one another, despite the existence of a bridge between the two. This is the definition of discordant redshift, by which the physical associations of many intracting objects studied by Arp, the Burbidges, et al are rejected by the mainstream. I was pleased to find out that even if you define "discordant redshift" as a differential as low as 275 km/s, for the bridged pairs in the sample, the smaller of the two galaxies is redshifted relative to the larger member 100% of the time. In fact, except for the 5 bridged pairs with differentials larger than 1000 km/s, all the bridged pairs show differentials that are small enough to result from peculiar motion - the highest differential is only 361 km/s. There is some very interesting stuff going on here when you apply some basic stats to these velocity differentials.

    And to counter Cougar's suggestion that the differentials are not statistically significant, if we leave out the 5 systems in which the redshift is highest that still leaves 19 systems in which the small companion is redshifted relative to the host vs 10 systems where the reverse is true. These are all velocities less than about 360 km/s, which could certainly arise from peculiar motion. Interestingly, the redshift differential of the 19 systems in which the small companion has the excess averages 161 km/s vs a -77 km/s differential in the systems in which the host has the excess redshift. Clearly, something is going on here - and the implication is that bridges cannot safely be dismissed as chance alignments based solely on the redshifts of the interacting members.
    Last edited by turbo-1; 2006-Apr-13 at 07:16 PM.

  8. #1358
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    Quote Originally Posted by turbo-1
    It's the same data set. I inadvertently left out one 0 differential and one negative differential system, bringing the total number of systems to 41. No excuse for the sloppiness, except that I was working with a variety of media and didn't proof the post very well. I was just excited to bring this info to the thread.
    Thanks for the clarification. I had not gone back to note your edits on the original post.
    I have not fully digested what the ramifications of your numbers are, and I think this needs to be discussed further at some point, whether as a part of the bridge discussion or perhaps right after while it is still fresh in our minds.
    TomT

  9. #1359
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    Quote Originally Posted by TomT
    Thanks for the clarification. I had not gone back to note your edits on the original post.
    I have not fully digested what the ramifications of your numbers are, and I think this needs to be discussed further at some point, whether as a part of the bridge discussion or perhaps right after while it is still fresh in our minds.
    TomT
    I hope we can disuss the redshift differentials now because I extracted the data specifically for the bridge discussion, and it bears directly on the tendency for mainstream astronomers to reject the reality of bridges often based only on the differentials. The fact that the redshifts/blueshifts are not distributed evenly (about 2.5:1 more redshifted companions than blueshifted) and that the magnitudes of the average velocity differentials differ so widely are strong arguments for intrinsically redshifted companions. I hope that at least some of the supporters of mainstream astronomy will either acknowledge that there are statistical anomalies in the data or do their own analysis and prove that the anomalies that I pointed out do not exist.

  10. #1360
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    Quote Originally Posted by turbo-1
    I hope we can disuss the redshift differentials now because I extracted the data specifically for the bridge discussion, and it bears directly on the tendency for mainstream astronomers to reject the reality of bridges often based only on the differentials. The fact that the redshifts/blueshifts are not distributed evenly (about 2.5:1 more redshifted companions than blueshifted) and that the magnitudes of the average velocity differentials differ so widely are strong arguments for intrinsically redshifted companions. I hope that at least some of the supporters of mainstream astronomy will either acknowledge that there are statistical anomalies in the data or do their own analysis and prove that the anomalies that I pointed out do not exist.
    Are there any supporters of the concordance view that are willing to engage on these points? It is impossible to engage an opponent that has withdrawn from the field, but a refusal to engage is not really supportive of your position (duh!).

  11. #1361
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    Quote Originally Posted by turbo-1
    Are there any supporters of the concordance view that are willing to engage on these points?
    As moderator, I'm not willing to press here. Generally, I think you'll need to wait at least 24 hours before you can be sure no one is taking you up on this. The total BAUT traffic gets pretty slow in the evening, and perhaps a significant number of the people who would be addressing this are celebrating passover. I know nereid is just now coming back from being away from the computer for a while.

    For my part, I appreciated that the data was tabularized, but I haven't taken the time to sort out the data enough to know if there are some obvious biases that resulted in your red-blue ratios.
    Forming opinions as we speak

  12. #1362
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    Quote Originally Posted by turbo-1
    The trend was stronger than I had expected and extended to much lower redshift differentials than I had expected (100% of the small companions redshifted all the way down to 275 km/s).
    If we would be able to establish this trend with so low velocities, there would be two choices; 1) there are intrinsic redshifts, 2) the higher redshift galaxy is further out and not interacting with the lower redshift galaxy. Of course, the option 2 would mean that we would have to throw out practically everything we know about interacting galaxies.

  13. #1363
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    Quote Originally Posted by Ari Jokimaki
    If we would be able to establish this trend with so low velocities, there would be two choices; 1) there are intrinsic redshifts, 2) the higher redshift galaxy is further out and not interacting with the lower redshift galaxy. Of course, the option 2 would mean that we would have to throw out practically everything we know about interacting galaxies.
    Option 2 would require so many low-probablility chance associations (tail, tidal stream, or other bridge neatly superimposed on background objects) that we can safely rule that one out.

  14. #1364
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    I am assuming that tidal streams are different from the alleged bridges to quasars because they exhibit a range of redshifts throughout the stream, as opposed to being either the redshift of one object or the other. I seem to remember reading a paper or two that looked at the details of redshift of the tidal streams of NGC 4676 (Arp 242?).
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  15. #1365
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    Quote Originally Posted by antoniseb
    I am assuming that tidal streams are different from the alleged bridges to quasars because they exhibit a range of redshifts throughout the stream, as opposed to being either the redshift of one object or the other. I seem to remember reading a paper or two that looked at the details of redshift of the tidal streams of NGC 4676 (Arp 242?).
    We may have to work on the nomenclature a bit, so we don't talk past one another. What I consider a tidal stream is material that was pulled out of one object by another, similar to the arm of NGC 7603. NGC 4676 (the mice) have what are often referred to as tidal tails, and have been shown by Toomre and Toomre's simulations to arise from gravitational interaction during merger. We may have to resort to making explanatory statements and giving examples when talking about these different types of bridges. So far in these posts, we have given relatively short shrift to non-optical bridges, such as envelopes of dust and gas, etc that may show up in radio, X-ray, etc. These can be compelling evidence for interaction, even in the absence of an obvious optical bridge.

  16. #1366
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    Quote Originally Posted by turbo-1
    We may have to work on the nomenclature a bit, so we don't talk past one another.
    That makes sense. Does someone want to assemble "The Compleat Bestiary of Arp's Sub-Galactic Object Types", so that I can tell a tail from a stream from some other sort of bridge? Many discussion in the ATM section have run in useless circles until some definition of terms was agreed upon. Here's an opportunity to make one more way that this thread shines above the others here as a resource.
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  17. #1367
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    Quote Originally Posted by turbo-1
    The fact that the redshifts/blueshifts are not distributed evenly (about 2.5:1 more redshifted companions than blueshifted) and that the magnitudes of the average velocity differentials differ so widely are strong arguments for intrinsically redshifted companions.
    There are a couple problems with your analysis that do not allow me to reach the conclusion you seek. First, how exactly is a companion defined as opposed to a host? Is this relationship quantifiable?

    Disregarding the cases where there was no difference in redshift, we have 24 out of 33 compared to 9 out of 33. A chi-square test shows that, by golly, there is a statistical significance there at p<.05. But the problem is, where did this sample come from? You will definitely run into mainstream opposition when it is realized that this sample set was selected by... Halton Arp! We appreciate your tabulation and analysis, but for the reasons cited, I'm afraid the results have to be considered inconclusive. As we so often hear, more research needs to be done.
    Everyone is entitled to his own opinion, but not his own facts.

  18. #1368
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    Quote Originally Posted by Cougar
    There are a couple problems with your analysis that do not allow me to reach the conclusion you seek. First, how exactly is a companion defined as opposed to a host? Is this relationship quantifiable?
    The observation has been made that in bridged systems, the smaller companion galaxy is preferentially redshifted with respect to the larger host.

    Quote Originally Posted by Cougar
    Disregarding the cases where there was no difference in redshift, we have 24 out of 33 compared to 9 out of 33. A chi-square test shows that, by golly, there is a statistical significance there at p<.05. But the problem is, where did this sample come from? You will definitely run into mainstream opposition when it is realized that this sample set was selected by... Halton Arp! We appreciate your tabulation and analysis, but for the reasons cited, I'm afraid the results have to be considered inconclusive. As we so often hear, more research needs to be done.
    These galaxy associations were collected by Arp and Arp-Madore based on morphology, not based on redshift. As I have explained several times, the redshifts of most of the small companions and many of the host galaxies have still not been obtained after all these years. You cannot read a redshift bias into Arp's selection criteria, because he did not know the redshifts of these associations when he photographed them, except perhaps some of the NGC objects which had previously been studied. I don't think that we should resort to ad-hominem attacks (against Arp or anybody else) to dispute statistical results. It would be better to address the results directly. These redshifts are publicly available in NED and did not come from the Arp/A-M catalogs.

    There are many ways to look at these results, but the stark reality is that in the samples with redshift differentials, even if we throw out all the z>1000 km/s differentials (your trigger for non-interaction), there are still about twice as many redshifted small companions (19) as redshifted hosts (10) AND the average differential for the group with the redshifted companions is 161 km/s while the average differential for the group with the redshifted hosts is -77 km/s. Twice as many redshifted small companions as hosts and over twice as much velocity differential in the group with the redshifted smaller companions. And that's without the 5 systems with the highest differentials. That's a pretty significant result.

    Here is the table sorted by redshift, for those who want to make their own comparisons.

    Code:
    ARP #	excess V..km/s
    1	?
    2	?
    3	?
    4	?
    5	?
    6	?
    7	?
    8	?
    9	?
    10	?
    11	?
    12	?
    13	?
    14	?
    15	?
    16	?
    17	?
    18	?
    19	?
    20	?
    21	?
    22	?
    23	?
    24	?
    25	?
    0021-623	?
    0522-423	?
    2219-432	?
    0430-285	?
    0456-264	?
    0207-360	?
    2343-633	?
    2058-381	?
    0013-562	?
    0448-622	?
    2245-401	?
    1823-512	?
    0729-660	?
    0500-590	?
    2026-225	?
    0459-340	?
    0213-283	?
    1416-262	?
    0403-604	?
    0536-502	?
    0606-770	?
    0017-454	?
    1955-570	?
    0417-754	?
    0545-355	?
    0452-630	?
    0208-223	?
    0215-331	?
    0458-250	?
    1950-585	?
    0643-563	?
    1237-364	?
    2057-650	?
    2256-304	?
    0430-303	?
    1357-253	?
    0602-600	?
    0500-620	?
    0037-305	?
    0639-582	?
    2256-254	?
    0550-342	?
    1312-365	?
    2256-480	?
    0521-505	?
    1325-274	?
    2214-524	?
    1336-221	?
    1332-290B	?
    1000-255	?
    2306-465	?
    0321-670	not in NED
    0324-524	-260
    1	-180
    0523-400	-156
    1	-96
    2	-21
    3	-19
    4	-18
    5	-7
    6	-6
    7	-4
    55	0
    56	0
    57	0
    58	0
    59	0
    60	0
    0327-285	0
    1	2
    2	6
    1108-300	18
    1	28
    2	39
    3	41
    4	59
    5	71
    1304-333	81
    1	97
    2	123
    3	198
    4	275
    5	291
    6	293
    7	336
    8	348
    1353-272	354
    2105-332	361
    2100-381	1555
    1	4458
    2	8200
    0058-402	9642
    2052-221	36526

  19. #1369
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    Since it has been a couple of weeks I think a summary of the bridges discussion may be in order.

    Key points made from the Arpian perspective:

    1. Bridges are a sign of interaction in mainstream research. When present the mainstream interprets them as resulting from interaction.

    2. When redshift differentials exceed ~ 1000 km s-1, the mainstream will - on that basis - reject the pair as interacting in spite of the presence of a bridge and other evidence for interaction.

    3. The evidence for interaction goes beyond "looks like" in the Arpian examples. For example, the high z companions are typically emission line objects with evidence of bursts of star formation.

    4. NGC 7603 provides a very strong case for interaction and thus a genuine discordant redshift assocation. The bridge terminates at the position of NGC 7603b and has an old stellar population that may be interpreted as material pulled out from the disk of the Seyfert NGC 7603. The z=0.245 and z=0.391 objects are star forming HII galaxies with spectral line equivalent widths that better fit the EW-luminosity relation if they are dwarf galaxies at the distance of NGC 7603 than at their own redshift distances. The HII galaxies are elongated in the direction of NGC 7603b and NGC 7603 - another sign of interaction. The lack of a suitable companion with the same redshift as NGC 7603 suggests that NGC 7603b is the best candidate to have formed the bridge.

    5. Even among mainstream literature there are instances of apparently interacting objects with large redshift differences such as B2 1637+29 which has a redshift difference of 4100 km s-1.

    6. Mainstream supporters of the position that there are no large deviations from a smooth Hubble flow have not provided any evidence that cases such as NGC 7603 are not real interacting systems except for the redshift differences.

    On the basis of the more detailed discussion and evidence presented in my long posts there is strong reason for concluding that there is scientifically viable evidence that large deviations from the Hubble relation (on the scale of thousands of km s-1) do exist in the universe.

    So where do we go from here? I'd still like to see further discussion on some of the examples that have not yet been discussed - such as B2 1637+29. But if nobody from the mainstream POV is going to provide any additional arguments against the bridges evidence discussed to this point, we can declare the matter resolved here on BAUT to the extent that the mainstream has no answer and must be willing to accept that the bridges are a strong piece of evidence for the Arpian hypothesis that there are large deviations from the Hubble relation.

    The above can serve as a basis for moving forward and discussing additional aspects of the Arpian model. But if we're going to move forward past the bridges, then that means there must be acknowledgement from the mainstream supporters that the following statement is acceptable:

    "Bridges and other lines of evidence have provided a scientifically supported case that objects with significantly different redshifts may be interacting. Therefore, the Arpian hypothesis that large deviations from the Hubble relation may exist in the universe is empirically supportable with this evidence. These deviations apparently can be on the order of thousands and even tens of thousands of km s-1. The evidence presented for cases such as NGC 7603 is of a nature that has not been refuted by any mainstream arguments or evidence."

    I ask if at this point people on both sides of this debate are willing to accept the above. The reason I ask is that it may be time to move on to other topics. If mainstream supporters are unwilling to accept the above, then when will the counter-arguments be forthcoming?

  20. #1370
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    Quote Originally Posted by dgruss23
    I think a summary of the bridges discussion may be in order.
    I think you've provided a biased summary.
    Quote Originally Posted by dgruss23
    1. Bridges are a sign of interaction in mainstream research. When present the mainstream interprets them as resulting from interaction.
    This is a gross oversimplification and overgeneralization. Bridges are often -- not always -- regarded as indicative of interaction, but obviously only when the objects are in the same ballpark. Besides, as Antoniseb recently brought up: "Does someone want to assemble "The Compleat Bestiary of Arp's Sub-Galactic Object Types", so that I can tell a tail from a stream from some other sort of bridge? Many discussion in the ATM section have run in useless circles until some definition of terms was agreed upon." The term bridge has not been well defined. In fact, I heartily object to the use of the term since it inherently implies a connection, and whether we have a connection or not is the issue in question.

    Quote Originally Posted by dgruss23
    3. The evidence for interaction goes beyond "looks like" in the Arpian examples. For example, the high z companions are typically emission line objects with evidence of bursts of star formation.
    Again, the term "companion" assumes facts not in evidence. We can't let you frame the debate in this fashion. Star forming objects may provide additional circumstantial evidence for your position, but that hardly gets us "beyond reasonable doubt."

    Quote Originally Posted by dgruss23
    4. NGC 7603 provides a very strong case for interaction and thus a genuine discordant redshift assocation.
    The jury's out.
    Quote Originally Posted by dgruss23
    The bridge terminates at the position of NGC 7603b...
    I pointed out that something continues on past 7603B.
    Quote Originally Posted by dgruss23
    ...and has an old stellar population that may be interpreted as material pulled out from the disk of the Seyfert NGC 7603.
    Points like this seem very... opportunistic. Isn't this rather a posteriori?
    Quote Originally Posted by dgruss23
    The z=0.245 and z=0.391 objects are star forming HII galaxies with spectral line equivalent widths that better fit the EW-luminosity relation if they are dwarf galaxies at the distance of NGC 7603 than at their own redshift distances.
    According to one paper written by authors with a clear Arpian bias. I have no explanation for those things, nor am I sure one is needed.
    Quote Originally Posted by dgruss23
    The HII galaxies are elongated in the direction of NGC 7603b and NGC 7603...
    I totally disagree with this claim. The elongations do not point at 7603 or 7603B. They miss by a mile. Well, more than a mile.
    Quote Originally Posted by dgruss23
    The lack of a suitable companion with the same redshift as NGC 7603 suggests that NGC 7603b is the best candidate to have formed the bridge.
    Except for its redshift, obviously.

    Quote Originally Posted by dgruss23
    6. Mainstream supporters of the position that there are no large deviations from a smooth Hubble flow have not provided any evidence that cases such as NGC 7603 are not real interacting systems except for the redshift differences.
    Mainstream science has long established that the Hubble flow is the major contributor to redshift on cosmological scales. Additional contributors are known, such as gravitational redshift, but they are calculated to be minor in comparison. The mainstream met its burden of proof long ago. If you want to show that position is incomplete, that burden is on you. Bringing forward a few dozen seemingly anomalous apparently associated objects drawn from the hundreds of billions of objects in our visible universe does not exactly justify a ruling of summary judgment on the issue, even if you have a witness saying, "He had on HII sneakers and was wearing tails."

    Quote Originally Posted by dgruss23
    On the basis of the more detailed discussion and evidence presented in my long posts there is strong reason for concluding that there is scientifically viable evidence that large deviations from the Hubble relation (on the scale of thousands of km s-1) do exist in the universe.
    I think I can grant you that. The question is, is the evidence conclusive? I thought I saw an alien spacecraft last night. I had observational evidence! It turned out to be a helicopter.

    Quote Originally Posted by dgruss23
    So where do we go from here? I'd still like to see further discussion on some of the examples that have not yet been discussed - such as B2 1637+29. But if nobody from the mainstream POV is going to provide any additional arguments against the bridges evidence discussed to this point, we can declare the matter resolved here on BAUT to the extent that the mainstream has no answer and must be willing to accept that the bridges are a strong piece of evidence for the Arpian hypothesis that there are large deviations from the Hubble relation.
    I think not. Absence of argument is not argument for absence.... or something like that.

    Quote Originally Posted by dgruss23
    "Bridges and other lines of evidence have provided a scientifically supported case that objects with significantly different redshifts may be interacting. Therefore, the Arpian hypothesis that large deviations from the Hubble relation may exist in the universe is empirically supportable with this evidence. These deviations apparently can be on the order of thousands and even tens of thousands of km s-1. The evidence presented for cases such as NGC 7603 is of a nature that has not been refuted by any mainstream arguments or evidence."
    What would Galileo do?

    Quote Originally Posted by dgruss23
    I ask if at this point people on both sides of this debate are willing to accept the above.
    Uh... no.
    Quote Originally Posted by dgruss23
    The reason I ask is that it may be time to move on to other topics. If mainstream supporters are unwilling to accept the above, then when will the counter-arguments be forthcoming?
    As soon as I get that $500,000 grant so I can quit my job and research the matter over the next several years.
    Everyone is entitled to his own opinion, but not his own facts.

  21. #1371
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    Quote Originally Posted by dgruss23

    1. "Bridges and other lines of evidence have provided a scientifically supported case that objects with significantly different redshifts may be interacting.
    2. Therefore, the Arpian hypothesis that large deviations from the Hubble relation may exist in the universe is empirically supportable with this evidence.
    3. These deviations apparently can be on the order of thousands and even tens of thousands of km s-1.
    4. The evidence presented for cases such as NGC 7603 is of a nature that has not been refuted by any mainstream arguments or evidence."


    I ask if at this point people on both sides of this debate are willing to accept the above. The reason I ask is that it may be time to move on to other topics. If mainstream supporters are unwilling to accept the above, then when will the counter-arguments be forthcoming?
    I support the above statement by dgruss23 (my numbers added) and answer Yes to all 4 points. Regarding large deviations from the Hubble Relationship (points 2 and 3), I think that further discussion will clarify (as dgruss23 and others have stated) that the Arp hypothesis does not thow out the Hubble Relationship per se, but postulates an intrinsic component of the total redshift, and when this is accounted for, the remaining component or components do follow a Hubble type relationship (redshift vs distance).
    In answer to your requests for comments on the radio galaxy B2 1637+29, I do not feel qualified to respond, but await reading any discussion.
    I also feel that before leaving the bridge discussion, we should at least acknowledge that the galaxy NGC 3628 exhibits 2 additional types of bridges, a hydrogen plume and an Xray filament. The Xray filament contains 2 high redshifted quasars, ending on one, and the H1 plume ends on an object which is a probable quasar (redshift yet to be determined). The quasars, filament and plume are all aligned with each other and the minor axis of NCGC 3628.
    I would like to give kudos to dgruss23 for the scholarly presentation of his case, and to all for a high level discussion.
    TomT

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    Quote Originally Posted by Cougar
    As soon as I get that $500,000 grant so I can quit my job and research the matter over the next several years.
    If you were applying for such a grant, what are some of the Arpian topics you would propose researching?
    TomT

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    Quote Originally Posted by dgruss23
    I think a summary of the bridges discussion may be in order.
    Quote Originally Posted by Cougar
    I think you've provided a biased summary.
    By biased, do you mean a summary that advances facts of which you disapprove? Is not concordance cosmology biased?
    Quote Originally Posted by dgruss23
    1. Bridges are a sign of interaction in mainstream research. When present the mainstream interprets them as resulting from interaction.
    Quote Originally Posted by Cougar
    This is a gross oversimplification and overgeneralization. Bridges are often -- not always -- regarded as indicative of interaction, but obviously only when the objects are in the same ballpark. Besides, as Antoniseb recently brought up: "Does someone want to assemble "The Compleat Bestiary of Arp's Sub-Galactic Object Types", so that I can tell a tail from a stream from some other sort of bridge? Many discussion in the ATM section have run in useless circles until some definition of terms was agreed upon." The term bridge has not been well defined. In fact, I heartily object to the use of the term since it inherently implies a connection, and whether we have a connection or not is the issue in question.
    The use of the term "bridge" and the observation that bridges are sign of interaction are well-accepted, and not a "gross oversimplification". If two galaxies are connected by a bridge in radio, optical, X-ray, or share an extended molecular cloud, for instance, they are generally assumed to be interacting with one another. This evidence for interaction is denied by mainstream astronomers when the redshift differential is high, despite other compelling evidence for interaction. The simple faith that redshift is only due to the Hubble relationship drives this. As for the definition of "bridge" I remind you that Nereid said (before she went missing some 150 or so posts ago) that we should expect to discuss bridges in the context of other wavelengths - not just optical. She has an appreciation for the fact that bridges (apparent connections between astronomical bodies) can take many forms.

    Quote Originally Posted by dgruss23
    3. The evidence for interaction goes beyond "looks like" in the Arpian examples. For example, the high z companions are typically emission line objects with evidence of bursts of star formation.
    Quote Originally Posted by Cougar
    Again, the term "companion" assumes facts not in evidence. We can't let you frame the debate in this fashion. Star forming objects may provide additional circumstantial evidence for your position, but that hardly gets us "beyond reasonable doubt."
    When a galaxy is connected by a bridge to a companion, it is reasonable to call it a companion. It seems that the only objection you have to recognizing the association of bridged galaxies is their redshift differential. We already know of lots of local (MW) bodies that exhibit intrinsic redshifts, so why the blind adherence to the view that all extragalactic bodies cannot have intrinsic redshift? It is a view that cannot be supported-much less proven, yet it is implicit in every one of your arguments.

    Quote Originally Posted by dgruss23
    4. NGC 7603 provides a very strong case for interaction and thus a genuine discordant redshift assocation.
    Quote Originally Posted by Cougar
    The jury's out.
    Again, without measured redshift differentials, you would consider this an interacting system, just like any of us would. "Jury's out" sounds a lot like the creationists' mantra that evolution hasn't been proven.

    Quote Originally Posted by dgruss23
    The bridge terminates at the position of NGC 7603b...
    Quote Originally Posted by Cougar
    I pointed out that something continues on past 7603B.
    And I pointed out that what continues past 7603B is not the thin, well-defined tidal streamer, but an extenstion of the envelope of luminous material that surrounds the whole NGC 7603 system - another strong indication of interaction. The distortion of that envelope could not exist without some gravitational interaction, and the only body in the vicinity capable of that interaction is 7603B.

    Quote Originally Posted by dgruss23
    ...and has an old stellar population that may be interpreted as material pulled out from the disk of the Seyfert NGC 7603.
    Quote Originally Posted by Cougar
    Points like this seem very... opportunistic. Isn't this rather a posteriori?
    A posteriori? Pardon me, but things can only be observed after they happen (a posteriori) and the observations can only be interpreted after they have been made (a posteriori). The fact that you have drawn your conclusions only after additional observations were made and the redshifts of these bodies were obtained (a posteriori) can be dismissed with exactly the same meaningless argument. If you wish to characterize the arguments made here on this thread, please do so fairly.

    Quote Originally Posted by dgruss23
    The z=0.245 and z=0.391 objects are star forming HII galaxies with spectral line equivalent widths that better fit the EW-luminosity relation if they are dwarf galaxies at the distance of NGC 7603 than at their own redshift distances.
    Quote Originally Posted by Cougar
    According to one paper written by authors with a clear Arpian bias. I have no explanation for those things, nor am I sure one is needed.
    If someone's research yields results that happens to support one of Arp's interpretations of an observation does that make them automatically "biased" or invalidate their work? That sounds more like junior-high clique-iness than science.

    Quote Originally Posted by dgruss23
    The HII galaxies are elongated in the direction of NGC 7603b and NGC 7603...
    Quote Originally Posted by Cougar
    I totally disagree with this claim. The elongations do not point at 7603 or 7603B. They miss by a mile. Well, more than a mile.
    Each of the HII bodies are elongated toward their nearest large neighbor. If you insist that the elongations must be pointed directly at the cores of their neighbors, you are throwing away everything that we know about tidal interactions. The universe is a dynamic place and nothing comprised of this many individual bodies (a small galaxy has LOTS of parts) can be expected to assume a rigidly geometric configuration, especially in the presence of a very large neighbor.

    Quote Originally Posted by dgruss23
    The lack of a suitable companion with the same redshift as NGC 7603 suggests that NGC 7603b is the best candidate to have formed the bridge.
    Quote Originally Posted by Cougar
    Except for its redshift, obviously.
    Which I have shown statistically to be an unreliable indicator of distance.

    Quote Originally Posted by dgruss23
    6. Mainstream supporters of the position that there are no large deviations from a smooth Hubble flow have not provided any evidence that cases such as NGC 7603 are not real interacting systems except for the redshift differences.
    Quote Originally Posted by Cougar
    Mainstream science has long established that the Hubble flow is the major contributor to redshift on cosmological scales. Additional contributors are known, such as gravitational redshift, but they are calculated to be minor in comparison. The mainstream met its burden of proof long ago. If you want to show that position is incomplete, that burden is on you. Bringing forward a few dozen seemingly anomalous apparently associated objects drawn from the hundreds of billions of objects in our visible universe does not exactly justify a ruling of summary judgment on the issue, even if you have a witness saying, "He had on HII sneakers and was wearing tails."
    It is incumbent on mainstream science to explain all observations, not just the observations that support its assumptions. If mainstream science cannot explain the observations of "few dozen" anomalous associations, then something is wrong with mainstream science.

    Quote Originally Posted by dgruss23
    On the basis of the more detailed discussion and evidence presented in my long posts there is strong reason for concluding that there is scientifically viable evidence that large deviations from the Hubble relation (on the scale of thousands of km s-1) do exist in the universe.
    Quote Originally Posted by Cougar
    I think I can grant you that. The question is, is the evidence conclusive? I thought I saw an alien spacecraft last night. I had observational evidence! It turned out to be a helicopter.
    Ah, yes, sarcasm. So much more effective than rational counter-arguments.

    Quote Originally Posted by dgruss23
    So where do we go from here? I'd still like to see further discussion on some of the examples that have not yet been discussed - such as B2 1637+29. But if nobody from the mainstream POV is going to provide any additional arguments against the bridges evidence discussed to this point, we can declare the matter resolved here on BAUT to the extent that the mainstream has no answer and must be willing to accept that the bridges are a strong piece of evidence for the Arpian hypothesis that there are large deviations from the Hubble relation.
    Quote Originally Posted by Cougar
    I think not. Absence of argument is not argument for absence.... or something like that.
    Simple nay-saying is not acceptable, for either the Arpian or mainstream supporters. dgruss23 and I have put a lot of effort into this thread in the past weeks. If you can show that we are in error, please do so, and we will continue the discussion on bridges in light of your statements.

    Quote Originally Posted by dgruss23
    "Bridges and other lines of evidence have provided a scientifically supported case that objects with significantly different redshifts may be interacting. Therefore, the Arpian hypothesis that large deviations from the Hubble relation may exist in the universe is empirically supportable with this evidence. These deviations apparently can be on the order of thousands and even tens of thousands of km s-1. The evidence presented for cases such as NGC 7603 is of a nature that has not been refuted by any mainstream arguments or evidence."
    This statement is demonstrably true, especially the lack of mainstream refutation, apart from nay-saying, based solely on redshift differentials.

    Quote Originally Posted by dgruss23
    I ask if at this point people on both sides of this debate are willing to accept the above.
    Quote Originally Posted by Cougar
    Uh... no.
    Can you offer any reason why not, apart from the belief that interacting objects must have similar redshifts?

    Quote Originally Posted by dgruss23
    The reason I ask is that it may be time to move on to other topics. If mainstream supporters are unwilling to accept the above, then when will the counter-arguments be forthcoming?
    Quote Originally Posted by Cougar
    As soon as I get that $500,000 grant so I can quit my job and research the matter over the next several years.
    You have already formed the opinion that there is no major contributor to redshift beyond the Hubble relationship, even without the $500,000 grant and the years of research. Surely, that's a large committment to make on the basis of "all the mainstream people believe this, so I will too." A wise man once said "When you believe in things that you don't understand you will suffer. Superstition ain't the way."
    Last edited by turbo-1; 2006-Apr-15 at 12:08 PM.

  24. #1374
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    02-April-2006:

    Quote Originally Posted by Cougar
    I've got a lot more to comment on, particularly on the behemoth Corredoira, Gutierrez paper, which I think deserves a lot of criticism, but that will have to wait because.... I'm going skiing.
    04-April-2006:

    Quote Originally Posted by Cougar
    But let's get away from the generalities and look at some specifics. I still want to discuss the newer Lopez-Corredoira and Guitierrez paper that you linked to regarding NGC 7603... if I have time tomorrow.
    04-April-2006: a comment about a certain Lopez-Corredoira & Gutierrez gravitational lensing related statement followed by:

    Quote Originally Posted by Cougar
    Well, that's not about the bridge either. It's about the paper, which I find riddled with flaws. Maybe I'll have time tonight to express my criticisms of the authors' bridge assertions.
    05-April-2006:

    Quote Originally Posted by Cougar
    Plus, one of the few good points of the L-Corredoira, Gutierrez paper was how they mentioned that we tend to view interacting objects as if they are in the two-dimensional plane of the sky as viewed from Earth, which they are not.
    And now this:

    Quote Originally Posted by Cougar
    According to one paper written by authors with a clear Arpian bias.
    It's becoming obvious that you don't have anything substantial to say about Lopez-Corredoira & Gutierrez paper. These comments are meaningless if you don't tell what the bias/flaws are. (Well, there's one possible meaning for comments like these; trying to make the paper look bad, even if it's not.)

  25. #1375
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    Quote Originally Posted by dgruss23
    I ask if at this point people on both sides of this debate are willing to accept the above.
    I accept it, except the part about "any mainstream arguments or evidence". There is the Sharp paper giving some arguments and evidence about NGC 7603. So, I quess I wouldn't word it so strongly.

  26. #1376
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    Quote Originally Posted by Ari Jokimaki
    I accept it, except the part about "any mainstream arguments or evidence". There is the Sharp paper giving some arguments and evidence about NGC 7603. So, I quess I wouldn't word it so strongly.
    Fair enough. But the Sharp paper is dated in that better data and imaging from the last 5 years makes the chief arguments of that paper irrelevant. For example, one of their arguments was that the bridge extends beyond NGC 7603. But newer imaging shows the fine z=0.03 bridge within the larger bridge. And that finer bridge does terminate at the position of NGC 7603b.

    They also attempted to use the Faber-Jackson relation and found that both distances were compatible with the FJ relation - so that the FJ evidence was never evidence against Arp's interpretation in the first place.

    Turbo-1 and I have asked a number of times - Is there any evidence besides redshift that can be shown to argue against interaction in these NGC 7603 type cases? If the mainstream has nothing else, then we have established that there is a scientifically defendable/defended case that some objects may have large deviations from the Hubble relation.

    Mainstream supporters can acknowledge this point without saying that they think Arp's case is proven. All they would be saying - Cougar - is that on the matter of bridges, the bridges and additional evidence discussed are evidence for which at this time there is no compelling mainstream rebuttal. In other words, the scientific evidence supports the possibility that these large redshift deviations might be real.

    So we could then proceed to other aspects of Arp's model. If we did so the mainstream could present arguments against Arp's other claims/ideas. But if evidence was presented against any of those other claims the mainstream supporters could not then conclude that there is no evidence for large redshift deviations - because underlying all that discussion there is still the bridges evidence which the mainstream has not disproven.

    So either (1) the mainstream supporters here at BAUT are willing to acknowledge that the hypothesis that some objects in the universe possess large deviations from the Hubble relation is scientifically supported (not proven) by the bridges et al evidence and we could look at other aspects of Arp's model .... or (2) the mainstream supporters wish to present additional arguments in an attempt to show that the bridges are not support for the large redshift deviations hypothesis.

    Which is it?

  27. #1377
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    Quote Originally Posted by Cougar
    I think you've provided a biased summary.
    Turbo-1 answered your other points to my satisfaction. But I don't like this accusation that my summary was biased. You're imply that my summary was slanted such that there is truth in this matter that I am hiding.

    Long before my two long posts I said that I would demonstrate that bridges were evidence for interaction. I've done that. But more than that - I've repeatedly asked for an instance where mainstream researchers do not interpret a bridge as evidence for interaction*. If there were numerous cases where that was in fact so - then you could accuse me of a biased summary. I've asked you for such instances. I've asked that as a general question to mainstream supporters. Not one instance has been provided.

    So what truth am I attempting to hide? Show me where the supposed "bias" in my arguments has slanted the truth into something it is not.

    *Instances in which the redshift differentials are small.

  28. #1378
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    In post 1368, I reposted the redshift differential table for bridged Arp and Arp-Madore associations (NED data) in order of increasing redshift differential (to make analysis a bit easier) and offered this summary:

    Quote Originally Posted by turbo-1
    There are many ways to look at these results, but the stark reality is that in the samples with redshift differentials, even if we throw out all the z>1000 km/s differentials (your trigger for non-interaction), there are still about twice as many redshifted small companions (19) as redshifted hosts (10) AND the average differential for the group with the redshifted companions is 161 km/s while the average differential for the group with the redshifted hosts is -77 km/s. Twice as many redshifted small companions as hosts and over twice as much velocity differential in the group with the redshifted smaller companions. And that's without the 5 systems with the highest differentials. That's a pretty significant result.
    Is there a supporter of the mainstream view who can explain this disparity? Certainly, we do not inhabit a privileged location in the universe from which the majority of small companion galaxies flee! So what is the explanation if it does not involve intrinsic redshifts?

  29. #1379
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    Quote Originally Posted by turbo-1
    Is there a supporter of the mainstream view who can explain this disparity? Certainly, we do not inhabit a privileged location in the universe from which the majority of small companion galaxies flee! So what is the explanation if it does not involve intrinsic redshifts?
    I am sure that the other mainstream supporters are tallying up the evidence which could take a while. In the meantime, the Milky Way has quite a few companions (some of which are embedded within our galaxy, and have long tails or bridges connected to them). Do you think that any of them are showing intrinsic red shift? Certainly if all companion galaxies are fleeing, we should see a preponderance of evidence that our companions are mostly redshifted, but it is my understanding that they are not. Similarly, M31 has several comapnions, and they too do not seem to have a bias toward being red-shifted.

    What is it about our galaxy and M31 that prevent this intrinsic redshift from infecting our companions? I ask this rhetorically, since I am moderating, and cannot judge whether you are answering *my* questions fairly. Feel free to comment if you like. Mainstreamers, please feel free to reword this question more seriously if you like.
    Forming opinions as we speak

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    Quote Originally Posted by antoniseb
    What is it about our galaxy and M31 that prevent this intrinsic redshift from infecting our companions? I ask this rhetorically, since I am moderating, and cannot judge whether you are answering *my* questions fairly. Feel free to comment if you like. Mainstreamers, please feel free to reword this question more seriously if you like.
    It is going to be very difficult to accurately characterize our own MW system, since we are embedded in it. There is a nearby system that is easy to see in its totality, and the redshift differentials can be derived without significant redshift contamination due to the peculiar motion of the MW. Every single one of M81's smaller neighbors has an excess redshift WRT the host. Every one. Newman and Terzian said that there is a one in 12 chance that this can occur because there are 12 galaxies involved, totally ignoring the gravitational influence of the much larger host galaxy. I am prepared to give a thorough rebuttal of that silly notion and the paper containing it when the time comes, but I would prefer to stay on the topic of bridges as evidence of interaction and the distributions of the redshift differentials of those bridged objects. dgruss23 and I have been very diligent about answering all the questions put to us, and we are patiently waiting for some answers from the mainstream camp.

    Antoniseb - I have told you before, do not be shy about asking me questions just because you are a moderator. All I ask is that you use your mod status even-handedly and hold all participants to the same standards of behavior. I realize that the rules are more stringent for ATMers, but surely given the effort that some of us have been putting into this thread, we too deserve reasonable and prompt answers to direct questions - answers that have useful information in them instead of "You're wrong, and you're using biased information" with no substantiation, and repeating claims that have been thoroughly debunked in earlier posts. Thank you.

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