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Alternative cosmology: the arp-narlikar's variable mass theory

  1. May 18, 2008 #1
    Hi! I'm interested in alternative cosmologies and the variable mass hypothesis developed by arp and narlikar seems to explain better the discordant redshifts: but I can't understand how this theory calculates cosmic distances according redshift and time. Narlikar says that " We have here a flat spacetime cosmology in which light waves travel without spectral shift. How then do we explain redshift ? Consider a galaxy G at a given radial coordinate R, the observer being at R=0. A light ray leaving the galaxy at T0-R/C reaches the observer at time T0. Since the masses of all subatomic particles scale as T^2, the emitted wavelenghts go as m^-1 & t^-2.Hence we get the factor:

    1+Z=

    T0^2
    __________
    (T0-R/C)^2

    I don't understand....if a galaxy has a redshift z=6.5 for exemple, how distant from us is it ?
    There is somebody well up in these things ?? Thank you....
     
    Last edited by a moderator: May 18, 2008
  2. jcsd
  3. May 18, 2008 #2

    Wallace

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    Arp's theory hasn't changed in decades despite the wealth of new observations in that time. You haven't detailed what you mean by 'discordant redshifts' so I have to assume you mean the fact that there are some Quasars and galaxies near each other in the sky that have different redshifts? This might have been a problem when there were only a handful of known Quasars, which is when Arp came up with this idea, however there are many more known today (thousands? tens of thousands? I'm not sure of the exact number) and there is no longer any hint of the 'discrepancies' you refer to, that is to say the number of galaxy-Quasar nearby pairs seen is consistent with what would be expected from random chance line of site alignment and not the fact that these 'pairs' are actually nearby to each other in space. In addition the expanding universe model has made a number of predictions that have been verified observationally, such as the properties of the CMB, the presence of the baryon acoustic peak in galaxy redshift surveys, the light curve width and redshift relationship seen in Supernovae Type 1A spectra etc etc. Many of these can't be understood in the Arp model, effectively ruling it out.
     
    Last edited: May 18, 2008
  4. May 19, 2008 #3
    Discordant redshifts have been discovered also recently: for exemple in the Stephan's Quintet: one of the galaxy group, NGC 7319, has a redshift of 0.0225. A tiny white spot is a quasar discovered in 2003 either silhouetted in front of the opaque gas clouds or embedded in the topmost layers of the dust. The redshift of the quasar is 2.114. Pasquale Galianni, Margaret Burbidge, Halton Arp, V. Junkkarinen, Geoffrey Burbidge, and Stefano Zibetti, the astronomers who wrote the paper describing this discovery, also studied the dust clouds surrounding the quasar: Radio, x-ray and spectra observations show that this area is disturbed. These gasses are more turbulent than the gasses in other regions of the galaxy. That seems to indicate that something big and powerful has passed through, moving outward from the nucleus. In addition to the jet, the region of the galaxy near the quasar is glowing with an excess of low-density emission lines from ionized gasses. But nothing is "there" to light them up except the impossible quasar. This is not the first definitive disproof of the redshift = distance principle, although it may be the best to date. Halton Arp has been accumulating discordant redshift evidence since the late 1960's.
     
  5. May 19, 2008 #4
    And however my doubt is to understand cosmic distances according to this theory: who can help me ?
     
  6. May 19, 2008 #5

    Wallace

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    The more Quasars we find the more we find that happen to appear near galaxies. The point is not to focus on the handful of chance alignments but rather the vast majority that do not have these alignments, and also to note the expected number of alignments given the observed angular density of galaxies and Qausars.
     
  7. May 20, 2008 #6

    Chronos

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    This is an extreme claim that is poorly supported by this paper - and virtually ignored by the scientific community at large.
     
  8. May 20, 2008 #7


    Maybe it's ignored by the most of scientific community because puts in crisis big bang assumptions and with it years and years of honoured careers, degrees,....
    I would make clear here that I'm not for or against the big bang theory: I only say that some things don't fit in with: what about galaxies with Z high redshift (Z>5 or 6 !!) already formed with masses of billions of suns ? And quasars with high metallicity levels ?? And it can go on so.....
     
  9. May 20, 2008 #8
    Some links to variable mass hypothesis

    Ok ! Excuse me but I'm completely new to this kind of site and I've read later forum's rules :
    here some references and the links I have consulted when I proposed my first question:

    ://redshift.vif.com/JournalFiles/Pre2001/V0N09PDF/V0N09ARP.pdf

    ://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1996Ap%26SS.244..177N&link_type=ARTICLE&db_key=AST&high=3abd925d4714244

    ://adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1993ApJ...405...51N&link_type=ARTICLE&db_key=AST&high=3abd925d4714244
     
    Last edited by a moderator: May 31, 2008
  10. May 20, 2008 #9

    Wallace

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    The paper you linked to was published in 1993! This is my point, these ideas are long since ruled out by the enormous amounts of data obtained since then (not that it explained the data well even then though).

    As for this..
    This is pure fantasy, scientists love overturning long held views, even if they held them themselves for a long career. It is precisely what scientists are striving for. But it has to be supported by the evidence and if the evidence overwhelming supports the current model then it is very hard to do. Of course it is very easy for people to claim they have a better theory by willfully ignoring the evidence.

    As you point out, there are some things we don't understand about the current model, high metalicities at high redshift being one example. All this says is that we don't understand everything, which we knew anyway.
     
  11. May 20, 2008 #10
    Dan74, I completely agree with you last reply to me. Alternative theories have never got much exposure unless its proponents are well-known and respected.
     
  12. May 20, 2008 #11
    You're completely right. High metalicities is a big problem for the BB theory at those distances, according to many BB detractors. I have not heard any BB theorists as yet respond to this observation, other than maybe questioning the interpretations of the observation.
     
  13. May 20, 2008 #12

    Wallace

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    If alternative theories are proposed that do a better job than the 'main' theory then they become the prevailing theory and cease being 'alternative'. It doesn't matter who proposes them, if a theory fits it will fly in the end. That's not to say that the modern practice of science is devoid of any sociology, obviously the titles and achievements of someone are not ignored when considering what they have said, but none the less if a complete unknown comes up with something interesting scientists do listen.

    As a case in point, Halton Arp is still well respected for being a very good observer who has achieved a lot of great science. None the less his cosmological model is clearly unsupported by the evidence and hence is not respected. The cosmological community didn't simply believe Arp because of his reputation, his idea was judged on it's merits, or lack there of.
     
  14. May 20, 2008 #13

    Wallace

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    Here is where you make your fatal mistake. There is no such thing as a 'Big Bang theorist' that might be in opposition to a 'non BB theorist'. You are characterising scientific debate as if it was politics. Of course cosmologists don't come out and 'defend' the BB from possible anomalous observations. The very notion that you would expect that to occur belies a misunderstanding of the whole process.

    Scientists don't sign up to an idea and then spend their career trying to prove that idea over any other. Rather all observations, experiments etc are considered continuously in order to arrive at the best possible model considering all the evidence. The vast majority of the evidence points to a particular model. Despite this, not all predictions that model makes correspond to what we observe. This just says the theory isn't perfect. Maybe we should expect to see the metallicites that we see at high redshift since modeling the processes that increase metallicity is a very uncertain field. Maybe the predictions are correct, and the observations are pointing to problems somewhere else in the model. The point is we don't know everything and both theorists and observers are madly trying to work it all out. Possibly the resolution won't change the basic elements of the model, perhaps it will, but no one is out to 'defend' the model, but instead find a better one that does fit all the data. The improved model might be just like the old one with minor adjustments, maybe it will be fundamentally different but the point is that the evidence is always the driver.

    There is no one in the world who would characterize themselves as a 'Big Bang Theorist'.
     
    Last edited: May 20, 2008
  15. May 21, 2008 #14
    I don't know where the above quote came from but theorists such as Guth, Gamow, Leamartre, etc. etc. all were part of formulating the BB theory. Granted Hoyle supposedly named the theory. It would be simply semantics to say that they didn't call themselves
    BB theorists. If they didn't say it, it seems likely that's how they were characterized by most.

    Wallace, when a theory is in trouble, I believe, it is forcefully defended. A case in point was
    -- Verschuur when he asserted that intragalactic hydrogen radiates at the same frequency as the supposed CMB. By his published paper in the prestigious Astrophysical Journal, Nov. o7, he asserted that our satellites would not be able to tell the difference between the two therefore the map of the CMB would accordingly not be accurate. This implied for some that there might not be CMB, therefore no BB. Related publications asked the question, Big Bang or Big Goof? The response to this assertion, it seemed, was like a duck on a June bug. To call their response an attack, would not seem to be an overstatement.

    If you've spent your whole life working on and with a theory, it would seem natural that some would aggressively defend their life-long work. The other logic of your comment seems reasonable to me.
     
  16. May 21, 2008 #15

    Chronos

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    Just a side bar: It would be more accurate to characterize metallicity in high-Z entities as an evolutionary mystery. BBT merely constrains the time line. Stellar and galactic evolution are still poorly understood, hence, this a very weak argument against BBT.
     
  17. May 21, 2008 #16

    Wallace

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    Guth etc are theorists that came up with ideas that are part of the Big Bang model. But they are not 'Big Bang Theorists' in the way you used the term, i.e. those whose goal is to defend the Big Bang theory. If new evidence showed that the theory was untenable they wouldn't try and defend it but would try and make a new theory they fit the evidence. Hence they are theorist, not 'Big Bang theorists'.

    There are many many many reasons why intergalactic hydrogen would not give the same signal as the observed CMB. Verschuur's work was not attacked because it was 'anti BB', rather any 'attacks' focused exactly where they should, on the methodology, assumptions and predictions of his work. He made some errors, jumped to too strong conclusions and ignored much of the information present in the CMB that is not explained in his theory. The idea, like any, lives and dies on the evidence, and this one certainly died.

    But people don't spend their whole life working on a theory, the theory changes from day to day. That is to day the 'Big Bang theory' that exists today is different from the one we had last month, which differed from the one before that. The theory is constantly updating and changing.
     
  18. May 21, 2008 #17
    Those observers that asserted metallicity did so by studying the absorption lines of galaxies and determining the elements which when renormalized for the red-shift, seemingly showed elements in the periodic table of iron and heavier. At these great distances critics have asserted that this analysis was misconstrued. Seemingly there would be a good reason to doubt this observation because it would seem to challenge BB cosmology. In the near future either evidence will built up to be beyond dispute, as far as these observation, or numerous additional observations will show that their interpretation was wrong.

    We will soon find out.
     
  19. May 21, 2008 #18

    Wallace

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    The observations may not challenge BB theory, since we don't understand fully how to model the evolution of metallicity. It may well be that when we can model this better we might expect to find the observed metalicity at this high redshift. So it doesn't come down to either the observations or the BB being wrong, it is perfectly plausible that they are both correct.

    Modeling metallicity evolution requires understanding well the formation of the first stars, the formation of galaxies and the formation of AGN. We really only have sketchy ideas about these processes so doing cosmology via metallicity measurements is difficult, since we can't know for sure what we would even expect to see!
     
  20. May 21, 2008 #19
    Wallace, agreed,

    "The observations may not challenge BB theory, since we don't understand fully how to model the evolution of metallicity." But current theory would need to be changed. At the rate that we now see matallicity evolve, according to related theory, it would take 5 to maybe 8 billion years to produce the metallicity that we presently observe within the Milky Way, which is similar to what these observers claimed to see in those distant galaxies.

    Maybe if only very large stars formed in the very beginning. A great deal of Supernovae activity occurred within a billion years or so this might produce this kind of metallicity claimed. This however has been the history and problem with the BB theory. Almost ever year new observations require changes in the theory. Most theorists right now know little about viable alternative theory so it would seem likely that all they would do is keep changing BB theory.

    If you think the BB is correct and don't want to see it replaced then you might hope that there will be no more similar observations, or worse, similar observations at greater distances, that the ones that were already observed are shown to be incorrect interpretations, and that they don't keep finding more and more galaxies at continually greater distances.

    In general, at about 12-13 billion years you would expect to see the "dark ages" according to BB cosmology. If not the estimated age of the universe, according to the BB model, would need to continue going up. They also could change the way they calculate the distance of galaxies, or could propose that the red-shifts are magnified in some way by a Dark Energy effect or other alterations of theory.
     
  21. May 21, 2008 #20
    Don't worry PanTheory; Big Bang "theorists" will find the way to adjust this and all others parameters not in line with theory: age universe don't fit in ? No problem, they lower Hubble's constant value or insert things like 'cosmological constant', ecc..well, in october Hubble telescope should have a new powerful 'eye', the wfc3 that, if I don't mistake, will discover galaxies until a z=10 or so redshift: what it'll happen when and if they'll discover galaxies already well formed at this redshift?
     
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