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In article ,
robert bristow-johnson wrote: i thought (my amateur understanding) the other thing about quasars is that they are moving away from us real fast, putting them near the edge of our observable universe (and putting them back in time quite a bit). Not really. The redshifts of quasars - and thus their distances and ages - vary quite a lot. Here's a nice picture that illustrates this: http://www.2dfquasar.org/wedgeplot.html taken from the 2dF quasar redshift survey. You'll see there are plenty of quasars between 2 and 12 billion light-years away. I don't know why there's an apparent shortage of closer ones! The shortage of more distant ones happens for the reason you suggest: anyway, wouldn't it take a lot of time for a black hole to get that big, to eat everything else in reach, etc.? i thought that black holes represented something more "mature" in the universe than what distant (and young) quasars would be. WMAP data puts the universe at 13.7 billion years old - an implausibly precise figure, but that's what they say! The first stars formed around 200 million years after that. As far as I can tell after a few minutes searching, the oldest known quasar formed about a billion years after the Big Bang, with a redshift of 5.82: http://antwrp.gsfc.nasa.gov/apod/ap000419.html But, I don't think there are many this old. |
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John Baez wrote:
Not really. The redshifts of quasars - and thus their distances and ages - vary quite a lot. Here's a nice picture that illustrates this: http://www.2dfquasar.org/wedgeplot.html taken from the 2dF quasar redshift survey. Yes, it is nice. It rather shows that Arps redshift periodicity in quasars does not exist. You'll see there are plenty of quasars between 2 and 12 billion light-years away. I don't know why there's an apparent shortage of closer ones! ... Well, either we live at an exceptionally interesting time when the number of quasars is far less than in any other time, or there is something wrong with the assumptions. When this is combined with the very large scatter of quasar brightness versus redshift we can easily come to the conclusion that for quasars the redshift is not a reliable measure of distance. As Arp has argued, and as supported by a very reasonable theory by Narlikar (based on particles having a mass that depends on their region of "communication" with other matter), quasars may very well have an additional component to their redshift resulting from their young age. Yes, *young*, because they are ejected from galaxies along the axes according to Arp. Such an understanding explains a host of facts that are inexplicable in models in which redshift is a reliable measure of distance for quasars and galaxies: 1. The wide scatter of quasar brightness versus redshift. It shows the unreliablity of the redshift as a measure of redshift for quasars. 2. The lack of low redshift quasars, because they all have an additional "internal" redshift (in Arp's nomenclature). 3. The much greater number of quasars found near large close spiral galaxies, especially near the axes where they are ejected according to Arp. Burbidge has done a study confirming this. 4. A study that attempted to disprove this was a 1978 article in the Astrophysical Jouirnal 223:747-757, "The Nature of QSO Redshifts", Alan Stockton demonstrated that *some* quasars are at the same distance as galaxies with the same redshift. However his data shows that the suppossedly line of sight pairings of galaxies with quasars (i.e with different redshift) also prove that they are not at different distances. This is because the separations are smaller for higher redshifts, exactly what would be expected for true pairs at the same distance, but not for random line of sight pairs. See my web page at http://ray.tomes.biz/bigbangbung.html for more details and graphics. The only reasonable conclusion is that Arp has got some things right but not all of them. -- Ray Tomes http://ray.tomes.biz/ http://www.cyclesresearchinstitute.org/ |
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Ray Tomes wrote:
John Baez wrote: Not really. The redshifts of quasars - and thus their distances and ages - vary quite a lot. Here's a nice picture that illustrates this: http://www.2dfquasar.org/wedgeplot.html taken from the 2dF quasar redshift survey. Yes, it is nice. It rather shows that Arps redshift periodicity in quasars does not exist. You'll see there are plenty of quasars between 2 and 12 billion light-years away. I don't know why there's an apparent shortage of closer ones! ... The common thinking is that many galaxies goes through a state early in their lifes when they develop a quasar in their lifes. During this state a massive black hole in the galactic nucleus is accreting the surrounding matter be it stars or gas, but as the density drops in the neighbourhood of the black hole the activity will drop and the galactic nucleus will settle down in a more quiescent state. Therefore we expect that young galaxies are more active than the middle-age galaxies that we see around us today. Well, either we live at an exceptionally interesting time when the number of quasars is far less than in any other time, or there is something wrong with the assumptions. When this is combined with the very large scatter of quasar brightness versus redshift we can easily come to the conclusion that for quasars the redshift is not a reliable measure of distance. As Arp has argued, and as supported by a very reasonable theory by Narlikar (based on particles having a mass that depends on their region of "communication" with other matter), quasars may very well have an additional component to their redshift resulting from their young age. Yes, *young*, because they are ejected from galaxies along the axes according to Arp. There are severe problems with this explanation. Firstly if the quasars are actually ejected from galaxies, then we would expect to see some blue-shifted quasars, or at least we should be able to see galaxy-quasar pairs in which the quasar has a smaller redshift than the galaxy, but such pairs are not observed. Secondly, in the last 25 years a number of gravitational lenses have been observed. The classical kind of a gravitational lens consists of a galaxy that is lensing the light from a distant quasar, such that we see several images of the quasar surrounding the galaxy. We always find in these lenses that the redshift of the quasar is significantly larger than that of the galaxy, which is in complete accord with that the redshift is a good estimator of the distance to both the galaxy and the quasar. Ulf Torkelsson |
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Let Mas'r Legree alone, for breakin' in! De debil
heself couldn't beat Mas'r at dat!" said Quimbo. "Wal, boys, the best way is to give him the flogging to do, till he gets over his notions. Break him in!" "Lord, Mas'r'll have hard work to get dat out o' him!" "It'll have to come out of him, though!" said Legree, as he rolled his tobacco in his mouth. "Now, dar's Lucy,--de aggravatinest, ugliest wench on de place!" pursued Sambo. "Take care, Sam; I shall begin to think what's the reason for your spite agin Lucy." "Well, Mas'r knows she sot herself up agin Mas'r, and wouldn't have me, when he telled her to." "I'd a flogged her into 't," said Legree, spitting, only there's such a press o' work, it don't seem wuth a while to upset her jist now. She's slender; but these yer slender gals will bear half killin' to get their own way!" "Wal, Lucy was real aggravatin' and lazy, sulkin' round; wouldn't do nothin,--and Tom he tuck up for her." "He did, eh! Wal, then, Tom shall have the pleasure of flogging her. It'll be a good practice for him, and he won't put it on to the gal like you devils, neither." "Ho, ho! haw! haw! haw!" laughed both the sooty wretches; and the diabolical sounds seemed, in truth, a not unapt expression of the fiendish character which Legree gave them. "Wal, but, Mas'r, Tom and Misse Cassy, and dey among 'em, filled Lucy's basket |
#5
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sobs and tears and shouts of all present.
Many, however, pressed around him, earnestly begging him not to send them away; and, with anxious faces, tendering back their free papers. "We don't want to be no freer than we are. We's allers had all we wanted. We don't want to leave de ole place, and Mas'r and Missis, and de rest!" "My good friends," said George, as soon as he could get a silence, "there'll be no need for you to leave me. The place wants as many hands to work it as it did before. We need the same about the house that we did before. But, you are now free men and free women. I shall pay you wages for your work, such as we shall agree on. The advantage is, that in case of my getting in debt, or dying,--things that might happen,--you cannot now be taken up and sold. I expect to carry on the estate, and to teach you what, perhaps, it will take you some time to learn,--how to use the rights I give you as free men and women. I expect you to be good, and willing to learn; and I trust in God that I shall be faithful, and willing to teach. And |
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Ulf Torkelsson wrote:
There are severe problems with this explanation. Firstly if the quasars are actually ejected from galaxies, then we would expect to see some blue-shifted quasars, or at least we should be able to see galaxy-quasar pairs in which the quasar has a smaller redshift than the galaxy, but such pairs are not observed. No we wouldn't. The reason is that in this hypothesis of Narlikar and Arp, newly created matter that exists in quasars at the time of ejection has much lower energy, mass and frequencies than normal matter, i.e all spectral lines are moved considerably to the red. This variation may be a factor of 3 or more and so far exceeds any velocity component which is likely to be less than a .01 variation in z. As the quasar ages it comes into contact with surrounding matter (at the speed of light interactions) and this brings its matter into line with that surrounding matter. This appears to happen in a series of discrete jump in redshift ultimately becoming very close to galaxy redshifts. Arp has found cases where quasar pairs are found along opposite axes of large spirals and might have relative redshifts of e.g. 1.3 and 0.3 with the pairs having extremely similar values to each other. Secondly, in the last 25 years a number of gravitational lenses have been observed. The classical kind of a gravitational lens consists of a galaxy that is lensing the light from a distant quasar, such that we see several images of the quasar surrounding the galaxy. We always find in these lenses that the redshift of the quasar is significantly larger than that of the galaxy, which is in complete accord with that the redshift is a good estimator of the distance to both the galaxy and the quasar. For the above reason that the "internal" frequency is always a redshift, quasars will always have an equal or higher redshift than a galaxy at the same distance. To distinguish between the theories you need to find instances of quasars making gravitational lenses of galaxies. If Arp and Narlikar are right then there could be cases of quasars lensing galaxies with lower redshifts. The idea that all quasars are new galaxies is supported by Arp and Narlikar, except that the quasar ages are much less than is generally assumed based on redshift = distance. It is still the case that quasars evolve to galaxies. The larger galaxies are older in this theory and we do find support for this from the fact that the larger members of clusters generally are slightly bluer than the average member. In standard cosmology this is unexpected because if anything the larger galaxies would be more massive and possibly have a small gravitational redshift. To come back to the original topic - quasars with no host galaxy are the earliest stage when they have just been ejected from a galaxy, and when they have the highest internal redshift. -- Ray Tomes http://ray.tomes.biz/ http://www.cyclesresearchinstitute.org/ |
#7
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Ray Tomes wrote:
Ulf Torkelsson wrote: There are severe problems with this explanation. Firstly if the quasars are actually ejected from galaxies, then we would expect to see some blue-shifted quasars, or at least we should be able to see galaxy-quasar pairs in which the quasar has a smaller redshift than the galaxy, but such pairs are not observed. No we wouldn't. The reason is that in this hypothesis of Narlikar and Arp, newly created matter that exists in quasars at the time of ejection has much lower energy, mass and frequencies than normal matter, i.e all spectral lines are moved considerably to the red. This postulate does not have any basis in conventional physics. Matter behaving this way has never been studied in a laboratory. This variation may be a factor of 3 or more and so far exceeds any velocity component which is likely to be less than a .01 variation in z. As the quasar ages it comes into contact with surrounding matter (at the speed of light interactions) and this brings its matter into line with that surrounding matter. This appears to happen in a series of discrete jump in redshift ultimately becoming very close to galaxy redshifts. Arp has found cases where quasar pairs are found along opposite axes of large spirals and might have relative redshifts of e.g. 1.3 and 0.3 with the pairs having extremely similar values to each other. This just shows that you can explain any observed phenomenon by postulating some new physics. Secondly, in the last 25 years a number of gravitational lenses have been observed. The classical kind of a gravitational lens consists of a galaxy that is lensing the light from a distant quasar, such that we see several images of the quasar surrounding the galaxy. We always find in these lenses that the redshift of the quasar is significantly larger than that of the galaxy, which is in complete accord with that the redshift is a good estimator of the distance to both the galaxy and the quasar. For the above reason that the "internal" frequency is always a redshift, quasars will always have an equal or higher redshift than a galaxy at the same distance. To distinguish between the theories you need to find instances of quasars making gravitational lenses of galaxies. If Arp and Narlikar are right then there could be cases of quasars lensing galaxies with lower redshifts. I am afraid that you are missing my point here. My point is that in all gravitational lenses the lens is at a lower redshift than the lensed object. This gives a strong support to that the redshift is a good indicator of distance for both galaxies and quasars. The fact that we have never observed a high-redshift quasar lensing a lower-redshift quasar is a weak point for the Arp-Narlikar mechanism, though you may argue that that is because a quasar without a host galaxy would be much lighter than an ordinary galaxy. Then again quasars in general do have host galaxies, which is also a weak point for a mechanism that postulates that quasars are ejected from galaxies. The idea that all quasars are new galaxies is supported by Arp and Narlikar, except that the quasar ages are much less than is generally assumed based on redshift = distance. It is still the case that quasars evolve to galaxies. This begs the question where the quasars find the material to make galaxies. Are we to postulate that they create that material on their own out of nothing? The larger galaxies are older in this theory and we do find support for this from the fact that the larger members of clusters generally are slightly bluer than the average member. This is a highly contentious statement for several reasons. Firstly it is patently wrong to claim that older galaxies are bluer than younger galaxies. Young galaxies are blue because they contain plenty of hot massive stars with short life times, while these stars are absent from older galaxies, which are therefore redder. Secondly there are several types of clusters of galaxies. Some small clusters like our local cluster are dominated by a few large spiral galaxies. Spiral galaxies are in general bluer than elliptical galaxies, since there is still star formation going on in spiral galaxies, while elliptical galaxies are almost devoid of gas from which new stars may be formed, and are therefore redder. On the other hand there are large clusters which are dominated by elliptical galaxies, in some cases one giant cD galaxy, which has grown to an enormous size by capturing smaller galaxies in its surroundings. In standard cosmology this is unexpected because if anything the larger galaxies would be more massive and possibly have a small gravitational redshift. This effect is completely negligible. The gravitational field that you need to achieve that effect is way beyond what is reasonable for any galaxy. To come back to the original topic - quasars with no host galaxy are the earliest stage when they have just been ejected from a galaxy, and when they have the highest internal redshift. it used to be true that we observed quasars at higher redshifts than galaxies, but that changed with the Hubble Deep Field, and we are now observing galaxies at equal or even higher redshifts than quasars, so I cannot find that there is any observational support for this idea. Ulf Torkelsson |
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Ulf Torkelsson wrote:
This begs the question where the quasars find the material to make galaxies. Are we to postulate that they create that material on their own out of nothing? The larger galaxies are older in this theory and we do find support for this from the fact that the larger members of clusters generally are slightly bluer than the average member. This is a highly contentious statement for several reasons. Firstly it is patently wrong to claim that older galaxies are bluer than younger galaxies. Young galaxies are blue because they contain plenty of hot massive stars with short life times, while these stars are absent from older galaxies, which are therefore redder. etc. etc. The details and mechanism of the ejection are not yet important here (and I think the models proposed are wrong, although Narlikar's C field is an interesting theory), only the hypothesis of association of galaxies and quasars of disparate redshift, and the theories will wait on the statistical evidence, if only the problem would be studied in earnest. A cursory glance at Arp's catalog will convince you that we are barely off square one. -drl |
#9
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In article , Ulf Torkelsson
writes: As Arp has argued, and as supported by a very reasonable theory by Narlikar (based on particles having a mass that depends on their region of "communication" with other matter), quasars may very well have an additional component to their redshift resulting from their young age. Yes, *young*, because they are ejected from galaxies along the axes according to Arp. There are severe problems with this explanation. Firstly if the quasars are actually ejected from galaxies, then we would expect to see some blue-shifted quasars, or at least we should be able to see galaxy-quasar pairs in which the quasar has a smaller redshift than the galaxy, but such pairs are not observed. Secondly, in the last 25 years a number of gravitational lenses have been observed. The classical kind of a gravitational lens consists of a galaxy that is lensing the light from a distant quasar, such that we see several images of the quasar surrounding the galaxy. We always find in these lenses that the redshift of the quasar is significantly larger than that of the galaxy, which is in complete accord with that the redshift is a good estimator of the distance to both the galaxy and the quasar. Thirdly, taking the ejection scenario at face value, one could observe a proper motion. As far as I know, no such proper motions (i.e. that indicate ejection from a nearby galaxy) have been observed. |
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Ray Tomes wrote in support of Halton Arp's theory - that
quasar redshifts are caused by newly created matter having longer wavelength spectral lines due to its constituent particles being less massive, due to mass being a property acquired by Machian particles which connect the particle to other matter in a sphere which grows at the speed of light after the particle's creation. However there's no evidence at all that newly created matter is any different from the old stuff - and everything to the contrary. Arp's theory has been rejected by most astronomers for this reason and others, such as his theory being incompatible with the vast amount of evidence showing that quasars and the like are powered by black-holes and their accretion discs. If you are in trying to explain quasars as being closer then usually believed, and can't figure out how the light could have been made in this redshifted state, then what is needed is a "redshift mechanism" which affects the light in transit. There's plenty of plasma or gas the light travels through where the average inter-particle spacing is longer than the coherence length of the light in question. So the wavefront (which is about as long in the direction of travel as the "coherence length") is basically travelling at full light speed through vacuum until part of it encounters a lone electron, proton, ion etc. Since we know the cloud of protons, ions and electrons slows down the light somewhat, we must conclude that the wavefront is slowed down by individual protons, ions and electrons, one at a time, creating a slight dimple in the otherwise flat wavefront as it propagates through space. In other words, these sparse plasmas are an inhomogeneous media. Since light carries momentum, anything which slows down the light gets at least a temporary kick of momentum, and can so be expected to move in the direction of the light. If you can figure out how such an interaction can leave the travelling wavefront somewhat redshifted, then you have a plasma redshift mechanism which would radically alter how we interpret the light which falls into our telescopes. I can't see a way of doing this with the traditional idea of a "photon" starting in one place, spreading out in space and eventually, entirely on its own, delivering its packet of energy to another place. Ari Brynjolfsson's "Plasma Redshift of Photons" theory apparently works on this basis, but I don't understand it: http://arxiv.org/abs/astro-ph/0401420 An alternative is the "photon" notion of electromagnetic radiation is to see the radiation itself as unquantitized, despite the observations that the way it is generated and absorbed does involve quanta proportional to frequency. In this model, the waves carry the probability of quanta being delivered, and so they carry energy, momentum etc. - but they are not individual "photons". Then all that is required is a mechanism by which these em waves are generally lengthened as they travel through sparse plasma. Such a theory, combined with the theory that the Universe is not expanding al-la Big Bang, would require that there be little or no observable redshift in signals such as narrow-bandwidth long wavelength microwave emission and absorption signals. So we would expect differing redshift between microwave signals observed with VLB to redshift of optical wavelengths from the same object. (Also, if the VLB signals come from clouds at the end of jets and most of the optical redshift happens nearer the core than the clouds.) It would require that there be less redshift for coherent signals such as emission and absorption lines in IR, optical etc. wavelengths where the coherence length of these signals gets close to or exceeds the average inter-particle spacing of the plasma it is passing through. Then, a good way of explaining high redshift quasars is that they are surrounded by a denser (than the inter-cluster medium) plasma, probably due to gravitational attraction, and that this redshifts the light we see from it at a more rapid rate per parsec than the ordinary inter-cluster medium. (In this model, the Lyman-alpha forest would be caused by a bunch of neutral hydrogen clouds embedded, and relatively close together, in this halo of plasma.) A plasma-redshift explanation for the cosmological redshift only needs to produce about one part in 14 billion per year travelling through the inter-cluster medium. If your plasma redshift model deposits energy in this plasma, then you can explain the inter-cluster medium being exceedingly hot - heated by dim starlight passing through it, and having virtually no way of cooling itself radiatively because the particles are so sparse they hardly ever come together in a coulomb interaction. Then you can explain the way clusters are like the soapy water between bubbles - the voids are exceedingly hot and therefore at a relatively high pressure, corralling the galaxies and their denser, cooler, gravitationally bound coronae, into the corners between the bubbles. The same process of heating and momentum deposition would probably also explain the heating and acceleration of the solar corona and wind. There are a whole series of problems with this, and I won't go on about it here. Unfortunately, due to lack of time and my own limited knowledge, I am not able to answer properly the thoughtful criticisms offered here in the past. I am not suggesting this is solid science, yet. I am addressing Big Bang critics, not supporters. I wish Big Bang critics would leave the Machian mass theory of quasars behind and work on something more promising, such as plasma redshift. I am not surprised that a "naked quasar" has been found. I think they are not so big or far away as usually believed, and that they are not necessarily found in the middle of huge galaxies. Maybe some of them are relatively close - just black holes which were ejected from galaxies after close encounters with other dense objects, and they go on to live a lonely life travelling through and between clusters, concentrating and devouring the otherwise sparse plasma in their general vicinity. - Robin http://astroneu.com |
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