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![]() "Bjoern Feuerbacher" wrote in message ... George Dishman wrote: "greywolf42" wrote in message .. . For a quick reference, see Perlmutter, Figure 3, Physics Today, April 2003, "Supernovae, Dark Energy, and the Accelerating Universe". http://www.slac.stanford.edu/econf/C...perlmutter.pdf snip Figure 3 is a picture of SN 1998ba. I can only guess that greywolf means figure 1. But even in that figure, I fail to see an exponential relationship between redshift and distance. So I *still* wonder where he gets the claim from that the detected curve is "exponential". The values at the right end of the graph are above a straight line projection of the low z values. That implies higher magnitude for a given redshift or conversely less red shift at a given magnitude. I think he interprets this as a lower redshift than if the predicted redshift were proportional to distance for all values: ... Pure Hubble constant (linear assumption) lies on the straight line. Again, this is just his strawman version in which H is constant in time. Straight line in which figure? Fig. 1 is *not* showing the relationship between redshift and distance! BTW, the term "pure Hubble constant" makes little sense. In *no* version of the BBT *ever*, the Hubble parameter was assumed to be constant *in time*! His entire argument relies on pretending that the relationship Hubble noted can be applied indefinitely. Of course that implies that, at great distances, the frequency would become negative, but it's only a strawman. Aside from punting significant aspects of history; L&S once again trot out an old myth (popularized by Misner, Thorne, and Wheeler; but never quantified), that "As critics still point out, any scattering process with energy transfer from the photon beam to the scattering medium, as required for a redshift, must broaden (deflect) the beam. This effect would cause images of distant galaxies to be fuzzier than their local counterparts, which they are not." The claim of "fuzziness" requires photons to scatter off of interstellar matter like little bowling balls. The last claim is simply wrong. Nowhere in the calculation are the photons treated as "little bowling balls". One uses the known relations for their energies and momenta (E = pc, following from Maxwell's equations, and de Broglie's formulas). I used the Klien-Nishina formula when I looked at the blurring argument earlier this year. I find it hard to understand how the idea could have been seriously considered. Merry Christmas George |
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greywolf42 wrote: IIRC, cosmogenic emissions of the CMBR are a BB assumption. Lucky for us observations of the Sunyaev-Zeldovich effect show that the CMBR is not a local effect. LOL! Here we go again. Another circular claim. And it's Zel'dovich, again! In what way is my comment a circular claim? And I don't care about the apostrophy or not. What fun. Do you mean this effect? http://groups-beta.google.com/group/...4452a1cfe33c0a You mean the one where the values for Ho are around 60-70, about what WMAP shows? I can describe the SZ effect without having to look at a reference to refresh my memory. Can you? If so, please describe it. |
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Greg Hennessy wrote in message
... In article , greywolf42 wrote: IIRC, cosmogenic emissions of the CMBR are a BB assumption. Lucky for us observations of the Sunyaev-Zeldovich effect show that the CMBR is not a local effect. LOL! Here we go again. Another circular claim. And it's Zel'dovich, again! In what way is my comment a circular claim? Your comment isn't circular. The reasoning for the "S-Z effect" is circular. And I don't care about the apostrophy or not. I wasn't commenting on the apostrophe. I was commenting on another Zel'dovich claim being placed out for target practice. Similar to the last time Zel'dovich was offered as an official source for support for the BB theory: http://groups-beta.google.com/group/...80ea678b332834 http://groups-beta.google.com/group/...42e81e40a679dc What fun. Do you mean this effect? http://groups-beta.google.com/group/...4452a1cfe33c0a You mean the one where the values for Ho are around 60-70, about what WMAP shows? I mean the one that didn't match observations, of course. I can describe the SZ effect without having to look at a reference to refresh my memory. Can you? If so, please describe it. Did you have a point to make? -- greywolf42 ubi dubium ibi libertas {remove planet for return e-mail} |
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N:dlzc D:aol T:com (dlzc) N: dlzc1 D:cox wrote in message
news:rbWyd.1801$8e5.1762@fed1read07... Gentlemen: "George Dishman" wrote in message ... "greywolf42" wrote in message ... ... The "formal definition" of the Hubble constant was made by Eddington, in the 1930s. It didn't have an H_0, IIRC. Citation please. Certainly. I don't own a copy of Eddington's book. Neither do I, and I haven't found his paper on-line. I can perhaps complete some references anyway: URL:http://www.iop.org/EJ/abstract/0959-5309/44/1/303 A presidential address, titled "The expanding universe", 1932 (I don't have access) Nor do I. So, this link is worthless to the open public, here. URL:http://www.phys-astro.sonoma.edu/Bru...sts/Eddington/ ... a little tiny bit on his life. Irrelevant. URL:http://www.amazon.com/exec/obidos/tg...02-6313517-538 1757?v=glance&st=* "The Expanding Universe : Astronomy's 'Great Debate', 1900-1931" published in 1933 (and I've seen this date as 1931, 1932, and 1933) ... be sure and click on "more" A good source for a book that will probably will bear on the subject. Does anyone have a copy that they can find a quote for or against either side? -- greywolf42 ubi dubium ibi libertas {remove planet for return e-mail} |
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George Dishman wrote in message
... "greywolf42" wrote in message ... George Dishman wrote in message ... {snip higher levels} Citation please. Certainly. I don't own a copy of Eddington's book. Neither do I, and I haven't found his paper on-line. So, I'll provide this excerpt from "Einstein and the History of Relativity", Howard & Stachel ed. "Cosmology from 1917 to 1960", by George Ellis. Section 2.6.2 begins: "REDSHIFT-DISTANCE RELATION. Meanwhile observations to consolidate the data on the Hubble diagram, confirm the linear velocity-distance relation, and determine the slope of this relation ("the Hubble constant') proceeded apace. The linear relation was criticized by Shapley (1929), but confirmed by de Sitter (1931b). The data were extended by Hubble and Humanson (1931), using a chain of distance indicators and observations extending the redshift range by a factor of 5 to 32 x 10^6 pc. They determined a value of H = 558 km/sec/Mpc for the Hubble constant. ..." "By 1936, Hubble had accumulated considerable data, summarized in his superb book THE REALM OF THE NEBLUAE, determining a value of 526 km/sec/Mpc for the Hubble constant. However, in all this work the interpretation of the observed relation was still uncertain; the velocities presented were regarded as APPARENT VELOCITIES (see Section 2.7). ..." {Italics in original as all capitals, above.} I think it is customary to use /obliques/ to indicate italics but it's less common than say asterisks for bold. That would work, too. But IMHO does't carry the emphasis as well into ASCII. I should also provide summation of the "present day" (1986) understanding of the BB model, from the same source (section titled "preliminaries"): "The present-day state of such a universe is characterized by three parameters: the Hubble constant H_0 - (R*/R)_0, the deceleration parameter q_0 = -(R'/R)_0 (H_0)^-2, and the present total density parameter rho_0 (which may represent contributions from various matter components); these quantities being related to Gamma by q_0 = (kappa rho_0 c^2 / 2 - Gamma) / 3 H_0^2, where kappa is the gravitational constant and c the speed of light." Note the slight difference in terminology between H and H_0 in the different quotes above; by the same author (Ellis). Both are claimed to be the Hubble constant. "H" is apparently not Hubble's variable choice. The key phrase that illustrates my point is "apparent velocities". When Hubble first published, he was noting an entirely empirical relationship. Then we agree entirely! The Hubble constant was not (originally) time-dependent. The latter was only added in the mid-1900s. In a steady state universe, one might expect the redshift from galaxies to be random regardless of distance and solely due to gravitational redshift. Galaxies heavier than ours would show a redshift while those lighter would be blueshifted. Any equation can be approximated as a power series but his data was too scattered to determine the second order coefficient but good enough to rule out a non-zero first order term. That alone was worthy of publication. Yes. Even though Wirtz was the first to publish such a relation. Hubble just confirmed Wirtz' observations. To go beyond the observation would mean making an assumption about the cause and something other than speed would extrapolate differently. Yes. A naive extrapolation would be that the speed of a galaxy remained constant over time. But the (original) "hubble constant" made no such assumptions. It was simply empirical. With that model separations would be zero at some finite time in the past. At half that time, all the galaxies would have the same speed as at present but be at half their present distance. The Hubble constant would then have twice the present value. Your logic is impeccable -- within the "naive" theory you are discussing. However, if you consider the effect of gravity, the speeds in the past would be higher, meaning the Hubble constant would be even higher. That means that Hubble would have been aware that the value he published would vary with time. If Hubble had been 'naive' enough to assume that redshifts are always due to velocities. However, as noted above, Hubble never made that assumption. He always qualified his redshifts as "apparent velocities." Ellis's use of H in the initial text relating to Hubble's determination of the first order coefficient You contradict the text. Ellis' quote was explicitly for the "Hubble constant" -- not a "first order coefficient." but H_0 when discussing the equations that involve the time dependence is entirely understandable. Of course it is "understandable" that way. However, it is not what was written. I am aware he showed the low z limit was proportional from observation but I haven't seen his formal statement of the law for other than the low-z case. Eddington didn't *have* one for other than what we call the 'low-z case' today. That's the point. That's my point too. Hubble's data covered such a small range of time that treating it as a constant was legitimate, but trying to suggest higher order coefficients could be determined from data with such a large spread would not have survived peer review. Again, Hubble *never* assumed that his data was speed. If you wanted to extrapolate from the low-z data to a general equation based on expansion, then you would use GR and in that H would be time dependent. Only if you assumed that redshift was always and only due to expansion/speed. I don't know who first did that. And that *IS* the core of our disagreement. Certainly your previous citation shows that Mattig did so in the 1950's, but I expect it was done long before that. I don't believe anyone ever published a version in which H was independent of time before Guth suggested inflation as a solution for the problems with the CMBR. My citation indicates that Mattig was one of the first. So far, your suspicions are just that. and now pretends that he thinks it a later addition to avoid admitting his argument is baseless. To which "definition" were you referring? Citation please. OK, I've provided a citation last round, and this round. Where is yours? snip However, the Mattig equations relate distance to observables which is not the Hubble Law so your quote is relevant anyway. I await your citation on when the change occurred. My argument is that there there never was a change. But you have no citations to support your claim. Even assuming constant speed and a linear relation between speed and distance, the Hubble constant varies with time. According to your modern theory, of course. I can't offer you a citation to prove that nothing suggesting otherwise was published. I guess one approach might be to look at Alan Guth's paper to see if he discusses any prior work on exponentially increasing speed (which is what a non-time varying Hubble Constant implies). Well, I gave you a secondary citation, above, that contradicts your point. Our disagreement in this thread revolved around whether the "Hubble constant" has "always" (i.e. from first mention of the term) been considered time-dependent. I don't see any advantage in us going around in this fashion again. So, if you (or someone else) finds an actual citation to H as a function of time -- prior to Eddington's 1933 book -- I'll agree that you are correct. snip The object of science is to compare theory with observation. Yet, Bjoern is well aware that the redshift-distance curve deviates away from the old BB predictions. .... Bjoern is well aware that the redshift-magnitude curve deviates from the simpler prediction but that isn't a redshift-distance curve. ???? It is just as much a redshift-distance curve as Hubble's initial straight-line (and all other, subsequent lines/curves). The luminosity (magnitude) is related to distance in standard-candle fashion. The missing link is how tired light predicts the magnitude will vary with distance. Already provided, numerous times. Why do you say it is "missing?" If you are saying it is just inverse square and the energy reduction due to red-shift then you have said that before but I thought you were also saying there was a reduction due to extinction and you haven't given details of that. There always is a reduction due to extinction, in any observation. However, the details of extinction are a graduate-level class in themselves. Extinction must be considered in making use of any 'standard candle' methodology. Or for any determination of absolute luminosity. {snip the "non-linear" misunderstanding} snip The cause is fractional removal of energy with incremental distance (the physical cause of the fractional removal varies with the theory). The resulting formula is I = I_0 exp (-mu x). OK, I thought you relied on a degree of extinction as well. No. Extinction (scattering and absorption by matter) is separate from tired light theory. Just like it is separate from standard candle assumptions. snip more on this - my mistake snip Tolman Test. You might like to find out about it but I don't want to be guilty of what I discussed with Bjoern, changing the subject before we sort out the details. Note the Tolman Test is very difficult and not very strong Well, in your view, *DO* the "macroscopic properties" disprove any version with exponential energy removal? (Regardless of whether you made this claim earlier, or not.) In my view, it falsifies Lerner's "intergalactis fog" as the source of the CMBR, it probably falsifies TVF's thermal equilibrium with a corpuscular aether ("Elyson particles") though that is perhaps easier to falsify by observing red shift at frequencies below the CMBR peak, and it falsifies Aladar's integrated starlight. Is that a 'yes' or a 'no?' (It was a general question. Not a request for a list of different theories that you consider disproven by different effects.) More to the point, I believe it could falsify your aether defect theory if you were to discuss it in sufficient detail to allow a quantitative analysis. That would depend on to which "macroscopic properties" you were referring. I also wouldn't consider my theory an 'aether defect' theory. But that's just word choice. Aside from punting significant aspects of history; L&S once again trot out an old myth (popularized by Misner, Thorne, and Wheeler; but never quantified), that "As critics still point out, any scattering process with energy transfer from the photon beam to the scattering medium, as required for a redshift, must broaden (deflect) the beam. This effect would cause images of distant galaxies to be fuzzier than their local counterparts, which they are not." The claim of "fuzziness" requires photons to scatter off of interstellar matter like little bowling balls. Yes, that's why they said "any SCATTERING process ...". It is not based on a single tired light assumption ... anywhere. It applies to those that used scattering to redden the light. But *NO* tired light theory uses scattering! A scattering theory would not be called "tired light". Tired light theories are called that because the light *itself* (photon or wave) loses energy *intrinsically.* Scattering processes are normal extinction. I disagree but it is perhaps just terminology. Extinction is discussed by Perlmutter ss "grey dust". The normal dust scattering reddens the light from distant objects by scattering blue more than red, but that is an intensity effect that leaves spectral lines unshifted. I think some people have suggested that small-angle scattering can reduce the energy of individual photons moving spectral lines and it is this variant of tired light that Wright was addressing. Let's look at Ned's statement in his webpage (November, 2004 version): "There is no known interaction that can degrade a photon's energy without also changing its momentum, which leads to a blurring of distant objects which is not observed. The Compton shift in particular does not work." Note that Ned's argument is not limited simply to Compton *variants* of tired light. His argument is explicit tha changes in momentum *ALWAYS* lead to blurring. This claim was made in MTW. And MTW -- in turn -- took it from Zel'dovich. Who had no real support for his claim, either. Ned's original page merely referred one to MTW. Now, Ned attempts to address the Compton shift: "The wavelength shift per scattering is proportional to 1-cos(theta) which is about 0.5*theta^2. Thus there can be no redshift due to the Compton effect unless there is a change in the direction of propagation. The change in angle per scattering could be less if there were more electrons (but Kierein already needs 1000 times too many electrons), but this would lead to more scatterings, and with more scattering the variances of the angles would add up to the same smearing." Of course, Ned has no support for this false claim. While a single-scatter event does follow Ned's equation, the multiple-scattering proposed by actual proponents of Compton scattering does *NOT* "add up to the same smearing". The proof of this is trivial. Take a double scatter, and assume that it is in the same direction as the first scatter (even this is *VERY* improbable), and use Ned's own equation. The scattering shift would be: 0.5 theta/2^2 + 0.5 theta/2^2 = 0.5 theta^2 (1/4+1/4) Precisely half the value of Ned's original single-scatter event -- which Ned says will be unchanged by multiple-scatter events. Of course, a random-walk anaysis could be done to see what the actual "smearing" might be. But Ned's analysis is completely false -- even for Compton electrons. Ned has simply tried to recreate Zel'dovich's old claim. But in so doing, he doesn't bother to address those little realities that Zel'dovich also ignored. The "tired light" description in my experience is a generic term that includes both the types using intrinsic energy loss as well as though in which some external agent is involved. That may explain why you didn't understand my talking of subsets earlier. I understand that your "experience" lumps strawman arguments with the actual theories. That *IS* the purpose of a strawman argument, after all. To confuse the issue, allowing an attack on a simpler (but ficticious) target. Which is why I have pointed out (repeatedly) that scattering has nothing whatsoever in common with tired light. Referentially or physically. The only people that even CALL photon scattering a "tired light" theory are people like Ned Wright -- who only use the claim as a strawman. I haven't looked at who suggested it but the first link I found on trying gives a number of pointers: http://www.eitgaastra.nl/timesgr/part1/2.html "According to Zwicky's tired light hypothesis the vibrations of light are steadily slowed down over long periods of time travelling through the universe, and so the redshift is the result of fatigue." That is what you seem to regard as tired light, A very imprecise summation of Zwicky. And it makes no distinction about the source of the redshift. however the page goes on to say: "[May 2003: Last year I noticed that many people have suggested the same tired light idea, i.e. light loses energy because of interaction with other (gravity/ether) entities in extragalactic space, see for example professor Assis2, professor Ghosh3, Dr. Van Flandern9 and various authors in Pushing Gravity5. End May 2003]" Also vague. As we see, below, Assis does not call all non-standard redshift "tired light." and specifically: "[October 2003: Also a mechanism like Compton scattering may be classified as a tired light concept75. I'm aware that this is the standard strawman classification. But I haven't read Mitchell, W. C. "Bye Bye Big Bang Hello Reality", either. Compton scattering is scattering of photons by particles (like electrons and protons) distributed in space, which are believed to result in energy loses and wavelengths that are redshifted in proportion to distance travelled. See also an article by Assis and Neves76 (next to Mitchell's book75) if you want to know more about the history and variety of tired light concepts. End October 2003]" Assis and Neves sounds like a reasonable reference: Assis, A.K.T., Neves, M.C.D. "The redshift revisited," Astrophysics and Space Science, Vol. 227, 13-24 (1995). However, the work is primarily a theoretical evaluation of steady-state cosmology versus big bang cosmology. It does give a series of statements that purport to summarize different proposals (numbered by me, not Assis): 1) "Louis de Broglie states a 'photon aging' due to a continuous loss of energy by the photon." 2) "Findlay-Freundlich believed in a photon-photon interaction in the intense radiation field of stars." 3) "Marmet believes in a redshift produced by inelastic collisions between photons on atoms and molecules." 4) "Reber and Kierein pointed out the Compton effect." 5) "Vigier and Monti proposed the resistivity of the intergalactic medium." 6) "Arp believes in an effect due to the age of celestial bodies." This is a listing of non-standard theories of the origin of redshift. It most certainly is not a listing of "tired light" theories. There *IS* a difference! Not all non-standard theories are tired light theories. Only numbers 1 and 5 are tired light theories. I think we can safely agree that 6 has nothing to do with tired light. Numbers 2, 3, and 4 -- while not standard cosmology -- rely upon the standard assumption that photons are perfect (and unlike any other waves in known science). "[May 2004: Professor Wright rules out Compton shift as a tired light model option, because Compton shift (for instance by electrons) would change the momentum of a photon, which would lead to a blurring of distant objects which is not observed94. He may be right about this. As we've seen above, Ned Wright's claim can be trivially disproven by his own assumptions and equations. However, tired light caused by ether/gravity particles is something completely different" Which is why I insist upon being correct in my use of terminology. Compton scattering (or any such scattering-off-matter process) does not result from a "tired light" hypothesis. It assumes that photons are perfect. Specifically, that they don't "tire" from mere propagation. So I think Tired Light is a more all-encomapssing term. That *IS* the purpose of creating such strawmen in the first place. Let's briefly examine the claim in item 4), above: "Reber and Kierein pointed out the Compton effect." We find no reference given for "Kierein" in Assis. (Kierein can be found at http://www.angelfire.com/az/BIGBANGisWRONG/index.html) Kierein does not use the term "tired light," in any variant. For Reber Assis gives: Reber, G., 1986, "Intergalactic Plasma", IEEE Trans. on Plasma Sci., Vol PS-14, pp 678-682. Only the abstract is available online: "Radio astronomy observations at 144-m wavelength suggest a plasma filling intergalactic space. This plasma may have one electron and proton pair per 100 cu cm. The plasma radiates hectometer waves by free-free transitions. The energy of electrons is replenished from visible light. It interacts with electrons by compton transitions. Accordingly, light tires as it travels through intergalactic space. Such is manifest by a shift in spectral lines toward the red proportional to distance. There is no need for an expanding universe." So, indeed, here a proponent using the term "light tires", while seriously proposing a compton effect for the redshift-distance relation! Though Reber seems to be definitely in the minority among proponents. -- greywolf42 ubi dubium ibi libertas {remove planet for return e-mail} |
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George Dishman wrote in message
... "greywolf42" wrote in message ... George Dishman wrote in message ... snip H_0 has the empirical value 71km/s per MPc which means dE/E is about 0.024% per MPc hence R is about 4.2GPc. Ah! Now I see where you are going. I think you are approaching this a bit sideways, but we should be able use this approach. However, my objection above to your use of H_0, was because H_0 is a theoretical value of the BB theory, not an empirical relation. The value isn't theoretical at all, in the sense that it could not be predicted from theory alone. But it isn't observable, either. H_0 contains "velocities". The observable is redshift. The empirical version would have units of delta lambda over lambda per MPc. (What is actually measured is *redshift* versus distance -- not speed per distance.) Exactly. Having made the measurement of redshift versus distance, in a model that explains the redshift by expansion or motion, We don't use models to make measurements. the measurements can most meaningfully be expressed as speed per distance while in a tired light interpretation the same information makes more sense in the form of a characteristic distance, or mu if you like, but it is easy to switch between those units. That's why I said the values were "related". The measurements can most meaningfully be expressed as just the way they were measured. But since you are then working with dE/E, we don't need to worry about the difference, here. snip And every photon loses about 63% of its energy every 4.2GPc, true? The current value of the slope of H_0 includes some specific BB assumptions. The best current value uses the angular power spectrum measured by WMAP and that method I agree is likely only to be applicable in a BB model. However, the older technique of measurements of nearby source for which distances can be found from the distance ladder using parallax, Cepeids and so on is equally valid for determining the constant in tired light models. The difference is that the uncertainty will be higher. The uncertainty in the observation of redshift vs. distance is unchanged. Regardless of how the WMAP theoreticians tweak their computer models. However, for the purposes of this exercise, I will accept your values are in the ballpark (roughly a factor of 2, if I converted correctly). That's another test you can apply to a tired light model. A factor of 2 is probably about as much as the uncertainty would allow but it would be hard to say without looking at the detail of the determination so I'm happy to accept that for the moment. The point is, that tired light theoreticians usually don't require that *ALL* the redshift be due to tired light. We try to avoid the trap that caught the big bangers. I.O.W., the redshift-distance relation may include contributions from different effects (at least in theory). Which could shift the onset of the nonlinear deviation. (For example, a combined Vigier-tired-light and plasma-"fireworks"-expanding-galaxies model.) Sidenote: LeSagians and tired light types usually use the variable mu; which may be calculated from material/aether properties (EM and gravitational). We typically don't use the resulting characteristic distance, R (which is back-calculated, or ad hoc). R and mu are inversely related. Your last two sentences appear to be in conflict. If mu can be derived from the theory, then just tkae the uinverse Tired light theories do not deal with universes. That's the big bang. and you have a theoretical value for R. That can then be compared to the observed value described above as a test of the theory. Neither value is ad hoc. The ad hoc referred to the use of tired light theory *solely* to explain the redshift (the way the big bang started). Values -- per se -- are never ad hoc. It is how they are used that obtains the ad hoc description. {brought over from parallel thread} Agreed, and since the value is now being measured by observation, it clearly meets your criterion. The point is, that neither the shape, nor value was predicted by the BB. It is another ad hoc fit to the BB. The shape of the curve *was* predicted by *all* tired light theories. The value was predicted by some. Ok, you have been reading the posts between Bjoern and me so can you clarify that. Yes, I've amused myself watching you and Bjoern pat each other on the back. You have said the exponential form fits the measurements, but in most tired light theories the energy is exponential with distance while what is observed is redshift versus magnitude or some other indirect measure of distance. You are correct that what is observed is redshift versus some indirect measure of distance (since we can't do parallax that far). Since energy is exponential with distance in tired light theories, so is redshift. Precisely which relationship between _measured_ values is predicted by tired light theories? The relationship between redshift and actual distance will be exponential. That is, at the low-redshift (low z) distances, you will have an apparently linear relation that is equal to the first part of the exponential series expansion. This relation will begin to deviate from linear as higher-order terms become important at longer distance. The entire curve will be exponential. Using your data, above, dE/E is about 0.024% per MPc. And every photon loses about 63% of its energy every 4.2GPc. -- greywolf42 ubi dubium ibi libertas {remove planet for return e-mail} |
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In message , greywolf42
writes Which is why I insist upon being correct in my use of terminology. Compton scattering (or any such scattering-off-matter process) does not result from a "tired light" hypothesis. It assumes that photons are perfect. Specifically, that they don't "tire" from mere propagation. So I think Tired Light is a more all-encomapssing term. That *IS* the purpose of creating such strawmen in the first place. Let's briefly examine the claim in item 4), above: "Reber and Kierein pointed out the Compton effect." We find no reference given for "Kierein" in Assis. (Kierein can be found at http://www.angelfire.com/az/BIGBANGisWRONG/index.html) Kierein does not use the term "tired light," in any variant. For Reber Assis gives: Reber, G., 1986, "Intergalactic Plasma", IEEE Trans. on Plasma Sci., Vol PS-14, pp 678-682. Only the abstract is available online: "Radio astronomy observations at 144-m wavelength suggest a plasma filling intergalactic space. This plasma may have one electron and proton pair per 100 cu cm. The plasma radiates hectometer waves by free-free transitions. The energy of electrons is replenished from visible light. It interacts with electrons by compton transitions. Accordingly, light tires as it travels through intergalactic space. Such is manifest by a shift in spectral lines toward the red proportional to distance. There is no need for an expanding universe." So, indeed, here a proponent using the term "light tires", while seriously proposing a compton effect for the redshift-distance relation! Though Reber seems to be definitely in the minority among proponents. You keep using the word "light", but hasn't a cosmological red shift also been demonstrated at radio wavelengths? -- What have they got to hide? Release the ESA Beagle 2 report. Remove spam and invalid from address to reply. |
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![]() "Jonathan Silverlight" wrote in message ... In message , greywolf42 writes snip So, indeed, here a proponent using the term "light tires", while seriously proposing a compton effect for the redshift-distance relation! Though Reber seems to be definitely in the minority among proponents. You keep using the word "light", but hasn't a cosmological red shift also been demonstrated at radio wavelengths? Yes, in fact the paper I cited earlier this year covers a frequency range of about 10^6 to 1 IIRC. The CMBR itself peaks in the microwave band. I am certainly using 'light' to mean EM in general in this context and I think greywolf is too. The phrase "Tired Light" is historical and refers to the phenomenon rather than the frequency band. George |
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In article ,
greywolf42 wrote: Your comment isn't circular. The reasoning for the "S-Z effect" is circular. What is circular about the reasoning for the S-Z effect? Let's start with on the same page. The following site seems best of a quick scan: http://www.mpifr-bonn.mpg.de/staff/mthierbach/sz.html Well, you proved you can look up the S-Z effect on a web page. That's something I guess. So much for the "effect." Now as to the application: "Observations of the CMB with radio telescopes (low frequencies) towards clusters of galaxies should show a diminution of the brightness temperature. The value depends on the properties of the intracluster gas (temperature, density, gas distribution), of course and is very small (~0.1...1*10-3 Kelvin). ... detection of the SZ effect verifies the cosmological origin of the CMB. Furthermore, combining the radio with X-ray observations of the measured cluster allows one to determine the distance of the cluster, and so to determine the value of the famous Hubble constant H0 ...). " The Hubble constant is used to determine the diminution of brightness. Then that is used to determine the Hubble constant. quot erat demonstrandum False. The "diminution of brightness" is an observable. You can then use this observed value to determine a value for the Hubble parameter. In actual fact, the variants are simply down in the noise of the data (10^-4 kelvin). You seem quite fond of claiming astronomical observations are noise. A good place to see this is the following page: http://cfa-www.harvard.edu/~aas/tenmeter/sz.htm Note the three levels of "corrections" that must be added ... including an ad hoc "optical depth" correction and ad hoc peculiar motion correction. I don't know why you think corrections predicted by the theory are "ad hoc", but they are needed for accurate work, and do not indicate a flaw with the procedure. In short it isn't the *idea* that is circular (hot electrons altering the CMBR curve, via multiple compton effect collisions). Well, here we agree, the S-Z effect is not a result of circular reasoning. I also have my doubts about photons that move from "scattering events", then only interact where we want them to (in specific "hot" regions, but not in intervening "cool" regions). Well, I don't know why you claim we "want" the scatterings in any particular place, but you only get the scatterings in hot regions because that is were the relativistic electrons are. You don't have relativistic electrons in cold regions. Because they are in reference to Zel'dovich's hand-waving style of argumentation. Well, as written, this is a ad hominem argument. Considering the person you are accusing of "hand-waving" is Zeldovich, I had a good laugh over it. The copy of the Sunyaev-Zeldovich paper is located at http://members.cox.net/~greg.hennessy/sz.pdf. Tell me what you think is "hand-wavy" about it. The theory predicts a decrement in the microwave background behind clusters of galaxies. I believe you mean "in the same direction as clusters of galaxies?" No, I don't mean that. If you understand the S-Z effect, you know it predicts a decrement in the background behind a cluster as compared to the background not behind a cluster. A decrement in the surface brightness is observed. And the value of this "decrement" is what? Please provide numbers, statistical significance, and citation. I think you'll find that it merely noise processing. A pretty good listing is located at http://nedwww.ipac.caltech.edu/level...w/Birk9_1.html. What part of this do you think doesn't match observations? Circularity doesn't mean that it doesn't "match". It means that the "matching" is illusory. In your last post you claimed it didn't match observations. Now you claim it does match, but the match is illusory. Please pick a stance and stick with it. I can describe the SZ effect without having to look at a reference to refresh my memory. Can you? If so, please describe it. Did you have a point to make? Yes, my point is I don't think you know what the S-Z effect is, nor why it is important to if the microwave background is a local effect or not. Then instead of simply claiming that I don't understand, why don't you demonstrate your knowledge of the S-Z effect, and how it shows that microwave background is not a local effect? We observe a decrement in the brightness tempature in the background when seen behing clusters. Since clusters are non-local, this proves that the background is non-local. Happy? |
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Greg Hennessy wrote in message
... In article , greywolf42 wrote: Your comment isn't circular. The reasoning for the "S-Z effect" is circular. What is circular about the reasoning for the S-Z effect? Let's start with on the same page. The following site seems best of a quick scan: http://www.mpifr-bonn.mpg.de/staff/mthierbach/sz.html Well, you proved you can look up the S-Z effect on a web page. That's something I guess. So much for the "effect." Now as to the application: "Observations of the CMB with radio telescopes (low frequencies) towards clusters of galaxies should show a diminution of the brightness temperature. The value depends on the properties of the intracluster gas (temperature, density, gas distribution), of course and is very small (~0.1...1*10-3 Kelvin). ... detection of the SZ effect verifies the cosmological origin of the CMB. Furthermore, combining the radio with X-ray observations of the measured cluster allows one to determine the distance of the cluster, and so to determine the value of the famous Hubble constant H0 ...). " The Hubble constant is used to determine the diminution of brightness. Then that is used to determine the Hubble constant. quot erat demonstrandum False. The "diminution of brightness" is an observable. *Apparent* brightness is an observable. "Diminution" from an otherwise expected value requires a theory for the expected value. You can then use this observed value to determine a value for the Hubble parameter. In actual fact, the variants are simply down in the noise of the data (10^-4 kelvin). You seem quite fond of claiming astronomical observations are noise. Only when we claim results in the region that is below the physical resolution of our instruments (i.e. the CMBR). And the CMBR is not necessarily an astronomical observation. A good place to see this is the following page: http://cfa-www.harvard.edu/~aas/tenmeter/sz.htm Note the three levels of "corrections" that must be added ... including an ad hoc "optical depth" correction and ad hoc peculiar motion correction. I don't know why you think corrections predicted by the theory are "ad hoc", but they are needed for accurate work, and do not indicate a flaw with the procedure. Well, these are 'corrections' needed to make the observations match theory. And the value for the optical depth and peculiar motion is not determined by any independent method, but by how one can make the results match theory. That's what makes them ad hoc. Ad hoc does not mean unreasonable. In short it isn't the *idea* that is circular (hot electrons altering the CMBR curve, via multiple compton effect collisions). Well, here we agree, the S-Z effect is not a result of circular reasoning. The idea isn't. The application is circular, however. I also have my doubts about photons that move from "scattering events", then only interact where we want them to (in specific "hot" regions, but not in intervening "cool" regions). Well, I don't know why you claim we "want" the scatterings in any particular place, but you only get the scatterings in hot regions because that is were the relativistic electrons are. You don't have relativistic electrons in cold regions. But you have non-relativistic electrons in cold regions. Which are assumed (by the S-Z methodologies) to have no effect whatsoever. In short, the S-Z theorists assume that the CMBR is affected solely by hot electrons, but never by cold electrons .... which make up the vast majority of electrons encountered by CMBR photons (from BB and S-Z theory). {'invisibly' snipped higher levels replaced, for later reference} =================== I wasn't commenting on the apostrophe. I was commenting on another Zel'dovich claim being placed out for target practice. Similar to the last time Zel'dovich was offered as an official source for support for the BB theory: http://groups-beta.google.com/group/...80ea678b332834 http://groups-beta.google.com/group/...42e81e40a679dc Since neither of those two url's have anything to do with the S-Z effect I don't know why you think they are at all relavent. =================== Because they are in reference to Zel'dovich's hand-waving style of argumentation. Well, as written, this is a ad hominem argument. It appeared that way only because you {invisibly} snipped the prior portions of the exchange. After first mistaking my comment for a complaint about your spelling of Zel'dovich. The original comment was an ironical laugh about big bangers on the group trotting out an authority that had been recently shown to be totally ignorant of the realities of astronomical observation. Zel'dovich really truly believed that stellar images on photographic plates were mathematical points (at least in 1963). And that basic misunderstanding was the foundation of his 'hand-wavy' style. Considering the person you are accusing of "hand-waving" is Zeldovich, I had a good laugh over it. The copy of the Sunyaev-Zeldovich paper is located at http://members.cox.net/~greg.hennessy/sz.pdf. You may want to check your source file. For some reason, I can only read pages 1-9 from that download file (I tried twice). Could you verify that all 17 pages are there? I obtained another copy from ADS (with all 17 pages). Tell me what you think is "hand-wavy" about it. AFAICT, the S-Z "effect" is a miniscule temperature shift (temperature fluctuations of relic radiation) on the order of 10^-4 or -5. It is this effect that S&Z spend all their time calculating. I only see one mention in the S-Z paper of what might be what you call "decrements" or diminution of brightness. This is a single sentence on page 5: "The value delta T over T mentioned above is the change of temperature measured by an observer moving together with the plasma: an observer on Earth also measures a change of intensity (fluctuation) due to the Doppler effect which equals delta T over T = (u / c) cos theta, where u is the velocity of the plasma and theta is the angle between the velocity and the direction of the observer." The above sentence is a classic hand-wave. Either that, or it's a poorly-worded reference to an effect derived by Sakharov (i.e. not the S-Z effect). I don't see any mention of intensity decrements in either the abstract, introduction, discussion (where details of predictions for delta T over T exist), or conclusion sections. Did I miss something? The theory predicts a decrement in the microwave background behind clusters of galaxies. I believe you mean "in the same direction as clusters of galaxies?" No, I don't mean that. If you understand the S-Z effect, you know it predicts a decrement in the background behind a cluster as compared to the background not behind a cluster. I understand that many people claim this as a "prediction" of the S-Z effect. Again, how do you observationally determine whether you are observing CMBR from "behind" a galaxy cluster, rather than from in front? All we observe are angular locations on the celestial sphere. A decrement in the surface brightness is observed. And the value of this "decrement" is what? Please provide numbers, statistical significance, and citation. I think you'll find that it merely noise processing. A pretty good listing is located at http://nedwww.ipac.caltech.edu/level...w/Birk9_1.html. I get an error that http://nedwww.ipac.caltech.edu/ and all permutations cannot be found. Are you sure this is the link you wanted? What part of this do you think doesn't match observations? Circularity doesn't mean that it doesn't "match". It means that the "matching" is illusory. In your last post you claimed it didn't match observations. Now you claim it does match, but the match is illusory. Please pick a stance and stick with it. I haven't changed "stance", I was discussing two references. Specifically: =============== greywolf42: Do you mean this effect? http://groups-beta.google.com/group/...4452a1cfe33c0a or http://groups-beta.google.com/group/...6741eab7ee267f Greg: {after "invisibly" snipping the second link} You mean the one where the values for Ho are around 60-70, about what WMAP shows? greywolf42: I mean the one that didn't match observations, of course. =============== I was pointing out the references, above, that the S-Z effect was not matching BB theory. Current papers are fully circular, as I have pointed out. {snip higher levels} Yes, my point is I don't think you know what the S-Z effect is, nor why it is important to if the microwave background is a local effect or not. Then instead of simply claiming that I don't understand, why don't you demonstrate your knowledge of the S-Z effect, and how it shows that microwave background is not a local effect? We observe a decrement in the brightness tempature in the background when seen behing clusters. How do we "see behind" a cluster? Or rather, how do you determine whether you are seeing "behind" or just seeing in the same direction as? Since clusters are non-local, this proves that the background is non-local. Happy? Yes, thanks. It's been a wonderful holiday season, so far. -- greywolf42 ubi dubium ibi libertas {remove planet for return e-mail} |
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