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Static universe - reply
On Apr 8, 6:49*pm, Eric Gisse wrote:
On Apr 7, 11:52 pm, davd wrote: [...] 1) Your 'analysis' of the Tolman surface brightness test from Lubin & Sandage amounts to reading their conclusion and saying 'nuh-uh!' You even *admit* that if the evolutionary relationship cited in the paper was used, that the agreement was excellent. Which in the very next sentence, without justification, you toss out the window to argue that there is no agreement. I am only taking the trouble to reply to you because the moderator said that "there is quite a lot of well-reasoned content". This is a complete misrepresentation of what I said. Let me repeat. Doesn't seem all that complete. Except for a very small disagreement about some numerical values which is irrelevant to the final analysis I completely agree with Lubin & Sandage's analysis including the *required luminosity evolution. What I disagree with them is that this evolution is reasonable. Yes, you disagree. You do not give a credible reason as to why the evolutionary models are incorrect, you just toss them out and use the raw value then proclaim victory. The disagreement is made slightly less credible by you not understanding that the (1+z)^-4 factor in the apparent luminosity comes from. It is two factors of (1+z)^-2, each from time dilation and expansion. Misrepresenting and misunderstanding a theory then basing further claims off that is a very dubious and dishonest proposition. It is funny that I state this in the paper! Furthermore is the fact that the nearby galaxies are brightest cluster galaxies (BCG) whereas the distant galaxies are normal cluster galaxies. It is well known that BCG galaxies are significantly larger and brighter than the expected largest member of a cluster. They did not discuss this so that I presume that they thought that the Kormendy correction (the strong dependence of luminosity on absolute galactic radius) would take care of the BCG mismatch. Using the BB angular size function the distant galaxies are on average approximately 0.26 time the size of the nearby galaxies which is much smaller than that expected from the BCG discrepancy. The ratio is 0.36 if a (1+z) factor is removed from the BB angular size function. With this correction I showed that the observed exponent for the surface brightness as a function of redshift is 1.03+\-0.16 which is in excellent agreement withe the expected value of one. And your justification for arbitrarily tinkering with the functions is what, exactly? Arbitrary tinkering? It is clearly explained Keep in mind your 'expected value' does not agree with the raw value either, so you'll need a nice large correction for your theory. It does agree within the paradigm of a static universe. Lubin & Sandage did examine a particular model for a tired light cosmology and claimed that it was inconsistent. My approach is much simpler and shows that a tired light cosmology can be completely consistent with these surface brightness observations. Finally the observed exponent using BB is 2.16+\-0.13 to be compared with an expected value of 4. This requires a luminosity evolution exponent of 1.84 which is very large. Without strong outside evidence this seems unlikely. Your entire argument rests on the wishing and hoping that there are zero evolutionary differences for multiple different galactic clusters. You have not justified your claim that it is 'very large', at least in the sense that you think it is larger than it ought to be. What do you mean by "zero evolutionary differences for multiple different galactic clusters" What about galaxy interactions. It seems that a significant number of galaxies have had collisions that may have reset their evolutionary clock. There's a difference of /_\z ~ 0.1 between each cluster. Short of looking it up myself to confirm, I can tell you that those clusters are not gravitationally bound and are rather distant to the tune of ~billion light years. That would be a radial distance, at least. Exactly how distant would require a literature search, but I am convinced that they are far enough away that there's no sane reason to argue that they are all at the exact same point in their evolutionary history which is EXACTLY what you are trying to argue whether you know it or not. ??? 2) Your 'analysis' of the various CMBR temperature measurements at non- local distances is literally nothing but you saying 'but physics is hard! I don't believe you!' What utter rubbish! You have failed to understand the argument that I made. What argument? Not a rhetorical question. There is no reasoned argument for me to 'not understand'. You point out that the column densities of the plasma need to be reasonably well known, then you wander off and say 'well in MY THEORY, light behaves in a fashion NEVER BEFORE SEEN in a plasma so I am going to be skeptical! Not a verbatim quote, but close enough. You use your theory to inject false uncertainty in multiple independent measurements at various redshifts, using arguments that do not have any basis in current electromagnetic theory. If we are arguing about which cosmological theory best fits the observations we must be consistent about keeping each argument within its own paradigm. It is this self consistency that is important. Seriously. This is your argument. No discussion of possible systematic errors, or how sensitive the observation is to various assumed models or even if that could be a factor. Just 'this is hard' and then you move on. 3) Your entire SN1a discussion is rather odd. I remember seeing some figures regarding Kowalski, et. al., ApJ (2008) before in a previous unrelated discussion. I could have SWORN that there were a rather solid amount of data points extending up to z=1.6. The project website and the relevant data slide (http://supernova.lbl.gov/Union/figur...agramSlide.pdf ) makes me wonder what's going on as the Union1 data set goes up to z=1.6. Clearly you have failed to properly read the axis label it is 2.5log(1+z) and not z. I noticed that. Not relevant. What is relevant is immediately previous was your cutoff of data points at z = 1.139 in the binning discussion. You repeat the explicit Only for that particular argument about expected densities. nature of the cutoff again in Table 6. Now if you'd like to argue you did, in fact, use the whole data set you'll seriously need to rewrite that section. Like, for example, why you need to bin the data and cut it off at arbitrary redshifts and magnitudes when the point of the exercise is to test the validity of a certain power law argument whose relevance is somewhat cryptic. Especially when you write this: "The results for bin six show that 33 out of 50 supernovae had an apparent magnitude brighter than the cut-o ff". What IS your point in that section, anyway? You don't even show the binning, or explain why the bin sizes are meaningful, or justify the procedure at all. You pick an arbitrary cutoff, and some members of a particular bin go past it. I'm just not seeing the significance. If you read the paper the binning is described in the description for table 6. Later usage refers directly to this description. If I have to go through the dataset myself to figure out what the hell you are talking about, you need to revisit your presentation of the material. You then argue that, in a bizarre and nonsensical fashion, that the lack of high-z supernovae is a problem for the concordance cosmology. Which struck me as odd not just because that's wrong, but because in the previous breath you were pointing out that there haven't been a large amount of searches for high-z supernovae. I never said that! Via Section 4.3.1: Exhibit A: "The results for bin one are not unexpected. It simply shows that there have been many more searches done for supernovae at nearby redshifts." [You never actually show the binning] See above. Exhibit B: "The problem with the BB results is that there is a dramatic shortage of supernovae in the high redshift bins." Now you probably could argue that you never actually SAID that there have not been a lot of high-z supernovae searches but I thought the implication was somewhat reasonable. You are arguing out of both sides of your mouth, to hedge your bets. You know damn well that quality light curves from high-z type 1a events are hard to find. If supernovae are well above the apparent magnitude cutoff why should observations of the light curve be difficult. [...] I note that you fail to criticize the analysis for gamma ray bursts, galaxy luminosity functions and quasar luminosity functions. I'm grabbing the low hanging fruit. I don't see the point of engaging an argument about a facet of the subject I don't understand too well when you have multitudes of problems in the areas I do know reasonably well. How convenient. Since the analyses for these objects are independent of each other a significant disagreement of any one of them with expansion is a serious problem for the current cosmological model. You don't even have an analysis in the cases I've looked at - you just take published papers and say 'nuh-uh'. |
#2
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Static universe - reply
On Apr 13, 5:29 am, davd wrote:
On Apr 8, 6:49 pm, Eric Gisse wrote: On Apr 7, 11:52 pm, davd wrote: [...] 1) Your 'analysis' of the Tolman surface brightness test from Lubin & Sandage amounts to reading their conclusion and saying 'nuh-uh!' You even *admit* that if the evolutionary relationship cited in the paper was used, that the agreement was excellent. Which in the very next sentence, without justification, you toss out the window to argue that there is no agreement. I am only taking the trouble to reply to you because the moderator said that "there is quite a lot of well-reasoned content". This is a complete misrepresentation of what I said. Let me repeat. Doesn't seem all that complete. Except for a very small disagreement about some numerical values which is irrelevant to the final analysis I completely agree with Lubin & Sandage's analysis including the required luminosity evolution. What I disagree with them is that this evolution is reasonable. Yes, you disagree. You do not give a credible reason as to why the evolutionary models are incorrect, you just toss them out and use the raw value then proclaim victory. The disagreement is made slightly less credible by you not understanding that the (1+z)^-4 factor in the apparent luminosity comes from. It is two factors of (1+z)^-2, each from time dilation and expansion. Misrepresenting and misunderstanding a theory then basing further claims off that is a very dubious and dishonest proposition. It is funny that I state this in the paper! Well, yes, otherwise I wouldn't be commenting on it. You claim there is one factor of (1+z) each from time dilation and expansion, and two from aberration. That's just wrong. Furthermore is the fact that the nearby galaxies are brightest cluster galaxies (BCG) whereas the distant galaxies are normal cluster galaxies. It is well known that BCG galaxies are significantly larger and brighter than the expected largest member of a cluster. They did not discuss this so that I presume that they thought that the Kormendy correction (the strong dependence of luminosity on absolute galactic radius) would take care of the BCG mismatch. Using the BB angular size function the distant galaxies are on average approximately 0.26 time the size of the nearby galaxies which is much smaller than that expected from the BCG discrepancy. The ratio is 0.36 if a (1+z) factor is removed from the BB angular size function. With this correction I showed that the observed exponent for the surface brightness as a function of redshift is 1.03+\-0.16 which is in excellent agreement withe the expected value of one. And your justification for arbitrarily tinkering with the functions is what, exactly? Arbitrary tinkering? It is clearly explained Yes, it is clearly explained that the number you picked gives you the answer you want. Beyond that, you have no actual justification. Keep in mind your 'expected value' does not agree with the raw value either, so you'll need a nice large correction for your theory. It does agree within the paradigm of a static universe. For the most literal value of 'static', where nothing ever moves or evolves through time. Because that's the only way it makes sense, given the redshift difference of 0.1 between each of the Tolman test galaxies. Lubin & Sandage did examine a particular model for a tired light cosmology and claimed that it was inconsistent. My approach is much simpler and shows that a tired light cosmology can be completely consistent with these surface brightness observations. Finally the observed exponent using BB is 2.16+\-0.13 to be compared with an expected value of 4. This requires a luminosity evolution exponent of 1.84 which is very large. Without strong outside evidence this seems unlikely. Your entire argument rests on the wishing and hoping that there are zero evolutionary differences for multiple different galactic clusters. You have not justified your claim that it is 'very large', at least in the sense that you think it is larger than it ought to be. What do you mean by "zero evolutionary differences for multiple different galactic clusters" What about galaxy interactions. It seems that a significant number of galaxies have had collisions that may have reset their evolutionary clock. To the same value? Across multiple galaxies? Don't think so. There's a difference of /_\z ~ 0.1 between each cluster. Short of looking it up myself to confirm, I can tell you that those clusters are not gravitationally bound and are rather distant to the tune of ~billion light years. That would be a radial distance, at least. Exactly how distant would require a literature search, but I am convinced that they are far enough away that there's no sane reason to argue that they are all at the exact same point in their evolutionary history which is EXACTLY what you are trying to argue whether you know it or not. ??? Fine, small words: Galaxies far apart live different lives. 2) Your 'analysis' of the various CMBR temperature measurements at non- local distances is literally nothing but you saying 'but physics is hard! I don't believe you!' What utter rubbish! You have failed to understand the argument that I made. What argument? Not a rhetorical question. There is no reasoned argument for me to 'not understand'. You point out that the column densities of the plasma need to be reasonably well known, then you wander off and say 'well in MY THEORY, light behaves in a fashion NEVER BEFORE SEEN in a plasma so I am going to be skeptical! Not a verbatim quote, but close enough. You use your theory to inject false uncertainty in multiple independent measurements at various redshifts, using arguments that do not have any basis in current electromagnetic theory. If we are arguing about which cosmological theory best fits the observations we must be consistent about keeping each argument within its own paradigm. It is this self consistency that is important. Yeah, well, you don't get to just go up and say a bunch of independent measurements from multiple authors are not credible 'because my theory doesn't agree with them'. No, saying 'but the measurement is hard!' doesn't discredit the result either, it just means it is worth thinking about the assumptions used. Typically it is observation that discredits theory, but perhaps I was taught the scientific theory incorrectly. You have no credible reason to disregard the observations, but you do so anyway purely because it proves your theory false. Now remind me, what's the difference between a scientist and a crank? [...] Exhibit B: "The problem with the BB results is that there is a dramatic shortage of supernovae in the high redshift bins." Now you probably could argue that you never actually SAID that there have not been a lot of high-z supernovae searches but I thought the implication was somewhat reasonable. You are arguing out of both sides of your mouth, to hedge your bets. You know damn well that quality light curves from high-z type 1a events are hard to find. If supernovae are well above the apparent magnitude cutoff why should observations of the light curve be difficult. Quick primer on Type 1a supernovae. The reason they are ever-so-handy is that, within a relatively tight margin, they have a constant absolute luminosity. Now, the amazing thing about an expanding universe is that if you have a little SN1a blinker out there at increasingly further distances it is going to be increasingly harder to SEE it by virtue of the factor of (1+z)^-4 that drags the apparent luminosity down into the toilet. It is a confirmation of the big bang theory that there are less SN1a's as you go further out, contrary to your goofy belief otherwise, given all other things being equal that they are VERY HARD TO SEE due to a reason I just mentioned. [...] I note that you fail to criticize the analysis for gamma ray bursts, galaxy luminosity functions and quasar luminosity functions. I'm grabbing the low hanging fruit. I don't see the point of engaging an argument about a facet of the subject I don't understand too well when you have multitudes of problems in the areas I do know reasonably well. How convenient. Since the analyses for these objects are independent of each other a significant disagreement of any one of them with expansion is a serious problem for the current cosmological model. Except there isn't disagreement. The only one you can say is even tenuous would be the Tolman surface brightness test, and that's only because of the modeling difficulty of taking into account the evolution of the galaxies. You don't even have an analysis in the cases I've looked at - you just take published papers and say 'nuh-uh'. |
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Static universe - reply
In article , Eric Gisse
writes: Quick primer on Type 1a supernovae. The reason they are ever-so-handy is that, within a relatively tight margin, they have a constant absolute luminosity. Now, the amazing thing about an expanding universe is that if you have a little SN1a blinker out there at increasingly further distances it is going to be increasingly harder to SEE it by virtue of the factor of (1+z)^-4 that drags the apparent luminosity down into the toilet. (1+z)^-4 refers to bolometric surface brightness and is independent of the cosmological model. However, SURFACE brightness isn't an issue in identifying supernovae (though it is if one needs to identify the host galaxy). Supernovae do get fainter at higher redshift, but not as quickly as (1+z)^-4, and the details depend on the cosmological parameters (otherwise we couldn't use them to measure the cosmological parameters). |
#4
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Static universe - reply
On Apr 14, 8:31 am, Eric Gisse wrote:
You claim there is one factor of (1+z) each from time dilation and expansion, and two from aberration. That's just wrong. Since i made a direct quote from Peebles in "Principles of Physical Cosmology", you must believe that he and other authors are also wrong! Yes, it is clearly explained that the number you picked gives you the answer you want. Beyond that, you have no actual justification. Where and what? To the same value? Across multiple galaxies? Don't think so. Of course the why would evolution be a function of z. Fine, small words: Galaxies far apart live different lives. But you require them to have the same dependence of evolution on redshift. Yeah, well, you don't get to just go up and say a bunch of independent measurements from multiple authors are not credible 'because my theory doesn't agree with them'. No, saying 'but the measurement is hard!' doesn't discredit the result either, it just means it is worth thinking about the assumptions used. Typically it is observation that discredits theory, but perhaps I was taught the scientific theory incorrectly. Precisely I have no argument with the observations but you seem to think that they are in excellent agreement with an expanding cosmology. I beg to differ. Show me where my analysis is incorrect. Quick primer on Type 1a supernovae. The reason they are ever-so-handy is that, within a relatively tight margin, they have a constant absolute luminosity. Now, the amazing thing about an expanding universe is that if you have a little SN1a blinker out there at increasingly further distances it is going to be increasingly harder to SEE it by virtue of the factor of (1+z)^-4 that drags the apparent luminosity down into the toilet. Please note that I referred to apparent luminosity. For local supernovae a constant luminosity is the same as constant energy. Where does your luminosity factor come from? Are you confusing supernovae luminosity and surface brightness. It is a confirmation of the big bang theory that there are less SN1a's as you go further out, contrary to your goofy belief otherwise, given all other things being equal that they are VERY HARD TO SEE due to a reason I just mentioned. If their apparent magnitude is well above the magnitude limit of the telescope why are they harder to see. Except there isn't disagreement. The only one you can say is even tenuous would be the Tolman surface brightness test, and that's only because of the modeling difficulty of taking into account the evolution of the galaxies. But I claim that for these objects there is disagreement and I provided an independent analysis for each object. For example the analysis for quasars clearly shows in the figure a very poor agreement with the standard model. [Mod. note: quoted text trimmed. Please do not quote text except where you are directly replying to it -- mjh] |
#5
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Static universe - reply
On Apr 14, 2:10 am, davd wrote:
On Apr 14, 8:31 am, Eric Gisse wrote: You claim there is one factor of (1+z) each from time dilation and expansion, and two from aberration. That's just wrong. Since i made a direct quote from Peebles in "Principles of Physical Cosmology", you must believe that he and other authors are also wrong! Aberration implies *proper motion*. You could make the case that through calculation of luminosity distance, you pick up one factor of (1+z) through time dilation and expansion each. Then through the calculation of angular size you pick up a factor of (1+z)^2 [summarizing a longer argument here], which is something that is correct. However, aberration does not play here. Might want to revisit your source and read the quote and its' context *very* carefully. Yes, it is clearly explained that the number you picked gives you the answer you want. Beyond that, you have no actual justification. Where and what? To the same value? Across multiple galaxies? Don't think so. Of course the why would evolution be a function of z. Fine, small words: Galaxies far apart live different lives. But you require them to have the same dependence of evolution on redshift. Are all the galaxies in the local group at the same points in their evolutionary path? The local group is a gravitationally bound structure, so it is local for cosmological purposes. Yeah, well, you don't get to just go up and say a bunch of independent measurements from multiple authors are not credible 'because my theory doesn't agree with them'. No, saying 'but the measurement is hard!' doesn't discredit the result either, it just means it is worth thinking about the assumptions used. Typically it is observation that discredits theory, but perhaps I was taught the scientific theory incorrectly. Precisely I have no argument with the observations but you seem to think that they are in excellent agreement with an expanding cosmology. I beg to differ. Show me where my analysis is incorrect. The problem is you don't have much in the way of analysis. I'm repeating myself here, which is getting boring. You reject the non-local CMB measurements. It has already been established that there are multiple observations (you have been given three now) with definitive error bars which with the local data point of z=0 is more than sufficient to establish the validity of the CMB being warmer as you look further into the past. You reject the Tolman surface brightness test. It has been established that your argument hinges on the rather dubious notion of no galactic evolution, which the authors kinda seriously disagree with. You reject the SN1a arguments for no rational reason. They do not support the static universe model, no matter how you bin and massage the data. Quick primer on Type 1a supernovae. The reason they are ever-so-handy is that, within a relatively tight margin, they have a constant absolute luminosity. Now, the amazing thing about an expanding universe is that if you have a little SN1a blinker out there at increasingly further distances it is going to be increasingly harder to SEE it by virtue of the factor of (1+z)^-4 that drags the apparent luminosity down into the toilet. Please note that I referred to apparent luminosity. For local supernovae a constant luminosity is the same as constant energy. Where does your luminosity factor come from? Are you confusing supernovae luminosity and surface brightness. Fine, I'll expand the argument further. An object some cosmological distance away has local luminosity "L". The relation between the absolute (local) luminosity and the measured luminosity "F" is L = 4\pi F d_L^2 where d_L is the luminosity distance to the external observer. The quantity 4\pi d_L^2 is the surface area of the sphere that encompasses all the emitted photons, which will be called "A". For non-local distances, the measured luminosity is going to get smaller. One factor of (1+z) each from expansion (directly makes A bigger) and time dilation (which comes from the time dilation of photon emission directly). This gives us F/L = 1 / A (1+z)^2. You can calculate the surface area directly from the FRW metric, but that is more involved than is needed here. Now, this surface area covers _the entire sphere_. We don't observe that - we observe a tiny piece of it. That little window laterally shrinks due to expansion, and if you imagine the window is a small square in (x,y,z) [with z pointing along the line between you and the source] it is rather easy to convince yourself that there is another factor of (1+z) for each side. Thus the falloff in luminosity goes as proportional to (1+z)^-4. It is a confirmation of the big bang theory that there are less SN1a's as you go further out, contrary to your goofy belief otherwise, given all other things being equal that they are VERY HARD TO SEE due to a reason I just mentioned. If their apparent magnitude is well above the magnitude limit of the telescope why are they harder to see. Why are you asking this? An object of absolute luminosity locally and the same object at z = 1 is going to be 1/16 less luminous. The same object at z = 1.5 is about 39 times less luminous. At z = 2, 81 times. Are you still unsure why things that are far away are hard to see? Except there isn't disagreement. The only one you can say is even tenuous would be the Tolman surface brightness test, and that's only because of the modeling difficulty of taking into account the evolution of the galaxies. But I claim that for these objects there is disagreement and I provided an independent analysis for each object. For example the analysis for quasars clearly shows in the figure a very poor agreement with the standard model. I like the bits where you copy and paste from the SDSS data release papers, without quoting. You would have been better off not calling attention to this section. Personally, I find poorly explained graphs rather unconvincing. That, and your principle assumption is dubious at best. Eg, http://arxiv.org/abs/0704.0806 Sure I know you cited DR3 and that's DR5 but I'm too lazy to care right this second. I note two things of worth from the paper: One: The intriguing similarities of language between the abstract and section 4.6 of your paper. Two: Figure 6. That looks a lot more like a Poisson distribution, and most certainly not Gaussian. Doubt the figure has changed significantly since the last few releases... You throw out an arbitrary curve for the "distance modulus" in your Figure 4, except there was absolutely zero discussion of how you obtained the big bang theory's prediction. No external references were cited for that, no discussion of the various cosmological parameters. Nothing. You do not have an analysis to disagree with. It is difficult to take you seriously at this point. [[Mod. note -- 3 excessively-quoted lines snipped here. -- jt]] |
#6
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Static universe - reply
On Apr 14, 1:34 am, Phillip Helbig---undress to reply
wrote: In article , Eric Gisse writes: Quick primer on Type 1a supernovae. The reason they are ever-so-handy is that, within a relatively tight margin, they have a constant absolute luminosity. Now, the amazing thing about an expanding universe is that if you have a little SN1a blinker out there at increasingly further distances it is going to be increasingly harder to SEE it by virtue of the factor of (1+z)^-4 that drags the apparent luminosity down into the toilet. (1+z)^-4 refers to bolometric surface brightness and is independent of the cosmological model. That is incorrect. The factor of (1+z)^-4 proportionality between the absolute luminosity is highly model dependent. Models that don't include expansion have different proportionalities between apparent and absolute luminosity. However, SURFACE brightness isn't an issue in identifying supernovae (though it is if one needs to identify the host galaxy). Supernovae do get fainter at higher redshift, but not as quickly as (1+z)^-4, and the details depend on the cosmological parameters (otherwise we couldn't use them to measure the cosmological parameters). Distances aren't the concern here, its' the luminosity falloff. |
#7
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Static universe - reply
In article
, Eric Gisse writes: (1+z)^-4 refers to bolometric surface brightness and is independent of the cosmological model. That is incorrect. The factor of (1+z)^-4 proportionality between the absolute luminosity is highly model dependent. Models that don't include expansion have different proportionalities between apparent and absolute luminosity. OK, I should have said "within the framework of cosmology based on the Robertson-Walker metric, using the Friedmann-Lema?tre equations etc". No aborigine dream cosmology, no Zeus, no angels pushing crystal spheres. |
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