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An anomalous concentration of QSOs around NGC 3079

  1. Oct 31, 2005 #1

    Garth

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    An anomalous concentration of QSOs around NGC 3079 by E.M. Burbidge, G. Burbidge, H.C. Arp and W.M. Napier - who else? Abstract:
    So allowing for the lensing pair there are 20 QSOs in the location, which represent around a one in a million chance. But are there not a million or so (indeed many more) such galaxies?

    Garth
     
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  3. Oct 31, 2005 #2

    Garth

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    From Table 1 of that paper. Red shifts of QSOs within 1 of NGC 3079.
    SBS0953+556 1.410
    4C55.17 0.900
    QO955+5623 0.066
    SBS0955+560 1.021
    RXJ10005+5536 0.216
    1WGAJ1000.9+5541 1.037
    NGC3073UB1 1.530
    ASV1 0.072
    SBS0957+557 2.102
    1WGAJ1000.3+554 2.680
    0957+561A 1.413
    0957+561B 1.415
    ASV23 0.900
    ASV24 1.154
    ASV31 0.352
    MARK132 1.760
    QO958+5625 3.216
    NGC3073UB4 1.154
    1WGAJ1002.7+5558 0.219
    1WGAJ1002.7+5541 0.673
    87GB100156.9+553816 0.431

    The red shift of NGC 3079 itself is 0.004.

    Now let me understand what the underlying alternative theory is...

    Hubble red shift in general is not cosmological due to the expanding universe but a 'tired light' effect caused by the photon's interaction with the ZPE? Is that correct?

    Then quasar red shift in particular is not cosmological but caused by either
    1. The quasars being ejected from the parent galaxy in whcih case why do not any of the quasars above have a red shift more blue than the parent galaxy - i.e. coming towards us?
    2. Their red shift is gravitational in nature on top of the tired light hypothesis.
    In which case why do they not exhibit evidence of a gravitational well - i.e. smeared out spectral lines - that extends over most of the z range?

    Am I missing something?
    Garth
     
    Last edited: Oct 31, 2005
  4. Oct 31, 2005 #3

    turbo

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    That interpretation of red shift is not embraced by Arp or the Burbidges, to my knowledge. That is a critical facet of my private theory, which I will not discuss here, so you can keep this thread alive.
    No, this is a common misinterpretation of their work. They believe that superimposed on their cosmological (distance-related) redshift and the redshift arising from relative motion, objects can also have large instrinsic redshift. In particular, they believe that quasars are ejected from active galaxies, and initially have a much higher redshift than the the host galaxy. As the quasar matures, its redshift moderates.
    It might be a good idea to read earlier papers on SS cosmology by Hoyle and Burbidge, and follow the citation list accompanying the paper. There may be someone on this board that feel qualified to defend their model, but I do not feel that I can do so. I do believe that they are correct in modeling quasars as smaller, nearer, and less energetic than they must be if we place them at the cosmological distances implied by their redshifts. As we find fainter and fainter quasars, we measure higher and higher redshifts, until now we have z~6 quasars that (if they are at the distances implied by their redshifts and our mass-luminosity relationship is correct) must mass several billions suns and reside in hosts of at least ten trillion solar masses.
     
  5. Oct 31, 2005 #4

    Garth

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    Okay one alternative is called "Plasma Cosmology"
    (Wikipedia article)

    But surely some will have been blue-shifted because they have been ejected towards us?

    Garth
     
  6. Oct 31, 2005 #5

    turbo

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    No. In their model, the redshift of quasars is intrinsic, and that redshift effect swamps the effects of redshift/blueshift arising from the Doppler effect (motion of the quasar relative to us). They also believe that the redshifts of quasars evolve over time.

    There have been a number of papers over the past few years positing mechanisms by which black holes can be ejected from a galactic core, including a slingshot effect and radiation recoil. (a Google search will pull these up for you). If a BH is ejected from a galaxy, what would we see initially? Unless the BH managed to tear out material and form some sort of accretion zone, we would see nothing (infinite redshift). As the BH accretes material from the IGM and forms a small tight accretion zone, we will see a faint object with an apparently very large redshift. As the accretion zone grows and light is emitted farther and farther from the gravitational well of the BH, we would see it become a brighter and brighter object with smaller and smaller redshift. That is one mechanism by which quasars can be local, and not have to be multi-billion solar mass objects capable of short-term flux variations. I have never seen the Burbidges, Arp, et al explain the nature of quasars in just this way, so please do not ascribe this mechanism to them - it's just my take on the rather enigmatic observations that they have made over the decades.

    One way in which this concept can be tested is to take a section of the sky and rigorously survey it for quasars. If quasars are local BHs and they follow an evolution path as they attract material from the IGM and form accretion zones, we would expect to see very few faint high-redshift quasars, with a smooth increase in their numbers at lower and lower redshifts, until they become indistinguishable from other AGNs that are more readily accepted as "local".
     
  7. Oct 31, 2005 #6

    Garth

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    Turbo - I can understand the red-shift being a local gravitatitonal-well effect: but two points.

    1. My comment "But surely some will have been blue-shifted because they have been ejected towards us?" was in response to your statement "In particular, they believe that quasars are ejected from active galaxies, and initially have a much higher redshift than the the host galaxy." I see now that you meant this red shift was produced intrinsically by the BH and not Doppler. However please note my confusion goes back to the original Hoyle-Burbidge theory of quasar red shifts, in which they were caused by the Doppler effect after ejection at relativistic velocities from the Milky Way.

    2. The intrinsic gravitational-well hypothesis would predict smeared out emission/absoption lines from plasma at different depths in the well. This is not observed is it?

    Garth
     
    Last edited: Oct 31, 2005
  8. Oct 31, 2005 #7

    turbo

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    I have been following these guys for a while, and I never got that impression, although perhaps in earlier Hoyle papers...? Do you have a link?

    I don't know. If light is propagating through a dense shell of gas, experiencing inelastic collisions, perhaps not.
     
  9. Oct 31, 2005 #8

    Garth

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    Sorry I do not, I was just dredging up that idea from the bottom of my memory.

    When Hoyle et al. suggested quasars were relatively local and ejected from local galaxies the non-observation of blue shifted quasars was difficult to explain. I believe that one modification was to suggest they were really local, faint and ejected by the Milky Way itself. Similar quasars ejected from other local galaxies might then be too faint to detect. However this was soon proved not to be the case. I read this explanation in a book in the 1960's and it could have been the author's own interpretation and not due to Hoyle et al. themselves.

    Garth
     
  10. Nov 1, 2005 #9

    Chronos

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    I was thinking the same thing Garth... Oh my goodness, 20 quasars too close to one... out of how many billions of galaxies in the known universe? What are the odds of that happening? I just saw this on CNN: Tonight's winning powerball lottery numbers are ... I did a quick, back of the envelope, calculation and deduced the odds of those particular numbers being picked are like one in 100 million. Does the term 'a posteri' have a familiar ring?
     
    Last edited: Nov 1, 2005
  11. Nov 2, 2005 #10

    turbo

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    Chronos, their model predicts overdensities of quasars around galaxies with active nuclei. Standard cosmology treats every such apparent association as pure chance, which is why the authors take pains to point out that statistically, the observed overdensities cannot be chance projections.

    If quasars are at the distances implied by their redshifts, they cannot arrange themselves WRT low-redshift objects such that they point at us like the "Fingers of God" effect seen in cluster maps. If even one of the qalaxy/quasar associations found by this group over the past couple of decades is real, concordance cosmology is in trouble. Here is my personal favorite:

    http://arxiv.org/PS_cache/astro-ph/pdf/0203/0203466.pdf

    Chance alignments?
     
  12. Nov 2, 2005 #11

    Garth

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    There are two well known red-shift mechanisms, Doppler and gravitational.

    Interpreting cosmological red-shift as a Doppler effect it is possible that there are two classes of quasar/QSO, one is distant, massive and bright that displays a Doppler red-shift, the other relatively nearby is smaller, less bright and ejected from active galatic cores but nevertheless displays an appreciable red-shift caused by gravitational red shift.

    The engine of both could be black holes - in two mass ranges - consuming material around them. Either type would have a combination of both Doppler and gravitational red-shift, though in standard quasars the gravitational component would be swamped by the Doppler.

    Thus some quasars could be associated with local galaxies and others truly cosmological and independent.

    Does this hypothesis make sense? Is it testable?

    Garth
     
    Last edited: Nov 2, 2005
  13. Nov 2, 2005 #12

    turbo

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    As a wise man once said "Entia non sunt multiplicanda praeter necessitatem." The universe is liable to be very simple at its roots, else the whole could not be expected to look so very much the same in every direction. It would be simpler to conceive of quasars as objects that exist on an evolutionary continuum, much the same as stars. It makes little sense to me that massive (several G solar mass) quasars can exist in massive, highly metallized hosts (minimum 10 trillion solar mass) at z~6, but that there are no such powerful beasts in our neighborhood.

    If quasars are BHs that are ejected rather naked from host galaxies and accrete matter from the IGM to become brighter and brighter (and less redshifted, as the accretion zones grow very large), we can conceive of a smooth continuum of quasar development. In this sense, high-z quasars need not be very distant - it's just that EM is being emitted from accreted matter very deep in the BH's gravitational well. This would neatly explain why many quasars are able to exhibit short-term variations in luminosity. Very huge extended objects should not be able to exhibit rapid variations in luminosity, but compact ones should be able to do so - especially as they tear up and accrete infalling materials of varying densities.

    These arguments have been known for years, but they have not gained traction because they would require us to decouple redshift from cosmological distance (in the strictest sense), and suddenly the most powerful tool of cosmologists (the Hubble relationship) becomes subject to revision on a case-by-case basis. Arp made a case for this when he pointed out that all eleven companions of M81 are redshifted with respect to M81. Statistically, this is darn near impossible if redshift is strictly due to a Doppler-like effect. Some of the comanions should be moving relatively perpendicular to our line of sight (z~M81), some should be moving toward us (z<M81) and some should be moving away from us (z>M81). All are redshifted, however. Are they all moving away from us en masse?
     
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