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Biggest problem I have with this and many ATM theories is this: they go backwards.
Let me explain: Theory attempts to explain unusual data. Fine. Theory argues with existing data and interpretations... well, okay.... Theory says everyone else is wrong and nothing can ever be predicted. Well, hold on there partner. The reason one is developing a theory is so that one can make predictions, not to explain why they can't be made ever. Allow me to expound on a few heavyweights and regulars: Ashmore and his paradox: No distances can be known, nor can anything be ascertained from spectra, luminosity, or parallax. The conclusion based on refusing to accept the concept of an expanding universe, rather than on new prediction or attempts at better prediction. No conclusions can be drawn, therefore the theory cannot be refuted or falsified. There is no difference in appearance between Ashmore's universe and the one we're observing, other than in his universe attempts at prediction based on physical experiment and extrapoloation fail. Halton Arp: No hard and fast rules exist for what one should see near any given galaxy, other than x number of galaxies look like they support it, and it gives no predictions. It also reduces the ability of any other cosmological theories to make predictions. No conclusions can be drawn, and most data has to be thrown away, as redshift is arbitrary, and "looks like" trumps empirical measurement and statistical analysis. By the way, a recent study done has come up with a reason why one would see more quasars around galaxies- gosh, it's because of gravitational lensing. Link here:Lensing of quasars based on large scale survey Arp may have been right about quasars appearing disproportionally around galaxies, but his explanations and further extrapolation were pure blue sky. Other even more esoteric theories such as electric universe theories and the like also suffer from this. If gravity is electric, why doesn't my toaster float? Without an explanation for even that simple thought experiment, it flows down the tubes of arbitrary plumbing faster than most. This whole rigamarole of denial and misdirection gives ATM ideas a bad name. Predict. Dammit, I'd better repeat that. Predict, make testable and useful differentiations between current theory and your expected results, and admit when you are wrong. My own theory is in its fifth incarnation after simple attempts at prediction through basic thought expeirment failed, and I was forced to conclude that the theory was therefore wrong, and useless in its then current form. That should be the watchword of any ATM attempts: Predict! Don't just make up a reason why everyone else is wrong about current data interpretations. It really enhances the perception that ATM is all cranks and kookoo, and vice-versa... And the next time I see someone martyring themselves on the cross of Galileo just because a flaw was pointed out in their theory... (His grave, by the way, is a perfect hollowed cylinder at this point from all the spinning he's done. I've seen it!) This unwarrented rant brought to you by a sick child and too much time spent up helping said sick child play "ToonTown" to help him feel better. |
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This appears to be a fair description of the mechanism Ashmore is trying to describe, but Ashmore's electrons are in intergalactic plasma, so they aren't ever 'sitting still', they are very hot. We know from observation that electrons in both cold and hot plasmas perform SHM.
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there is no governor anywhere |
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It's where I address your misconception about this "SHM".
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papageno "Why waste time learning, when ignorance is instantaneous?" - Hobbes (Calvin and Hobbes) "It's all about context!" - Vince Noir (The Mighty Boosh) "I've never heard of such a brutal and shocking injustice that I cared so little about!" - Zapp Brannigan (Futurama) "...because the logic of the lines traced from reality is as poor of aesthetic value as it is strict in consistency. " - Paolo Bozzi (Naive Physics - free translation) |
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I have a ping pong ball in a pipe (electron bound in an atom) If I hit that ball, it is likely that it will hit a ball on the other end of the pipe at the same angle. Now, take a free-rolling ping pong ball. I hit that ball- it is much less constrained, so it is likely to hit at a not perfect angle. Hence, scattering. It's that simple. That's the difference that Ashmore is denying. If plasmas behaved like Ashmore wants, many things around us would be observably different. And no, physics does not suddenly change outside of earth just because Ashmore wants it to. For instance, fire would be able to refract images like a lens, not based on refractive differences due to air temperature. Fire and plasma balls and other plasma phenomena would behave like glass, complete with refractive indicies and the like. I could focus a beam of light with an electron gun (free electrons in a plasma state) - which you really can't do. |
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64 km/s/Mpc = 64 km/(s Mpc) 1 km = 1000 m and 1 Mpc = 3.08568025 x 10^22 m. => 64 km/(s Mpc) = 64 * 1000 m/(s * 3.08568025 x 10^22 m) Metres cancel out. => 64 * 1000 * 1/(s * 3.08568025 x 10^22) = 2.07 x 10^-18 1/s
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"Stupidity gets denser in a crowd" - Old Finnish saying. [My website and My BLOG] [Nimblebrain forums] |
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The largest crutch of expanding-space is Hubble's redshift=distance relation, which can be interpreted in many ways (none of which entirely fit observation). Ashmore's tired-light is one of the many alternatives to expanding space. Good point about Arp, nothing solid can come out of his work yet unfortunately. I think he is on the right track though, looking for strange objects that defy explanation is a great way to probe the limits of theory. ![]() Quote:
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These analogies do not work when you consider the motion of charge carriers, and analogies with gases are used. So, yes the behavior of charge density can be separated from the microscopic motion of the charge carriers. That was the point of my analogy with sound waves in air. If you like, you could use water: under the microscope you can observe directly Brownian motion, and sound waves do not affect the Brownian motion of single water molecule. Quote:
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But if I explain why Mursula's wording is misleading, then I am wrong. Quote:
But in principle, yes the basic plasma oscillation would the whole big honkin' volume. (Conceptually, this is no more exotic than the polarizability of atoms.) Quote:
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The charge carriers are indistinguishable from each other. Sop it is possible to separate the behavior of the charge density from the motion of charge carriers. Quote:
Also, thanks to Ashmore's references, the SHM at high temperature occurs when they shoot the plasma with a big honkin' laser: it is a forced oscillation. EDIT to add: it is a forced oscillation because the electric field from the high-power laser light makes them oscillate. The electrons would not oscillate on their own. *We can get plasma-like behavior in condensed matter. Debye worked on electrolytic solutions, electrons in metals have plasma-like behavior.
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papageno "Why waste time learning, when ignorance is instantaneous?" - Hobbes (Calvin and Hobbes) "It's all about context!" - Vince Noir (The Mighty Boosh) "I've never heard of such a brutal and shocking injustice that I cared so little about!" - Zapp Brannigan (Futurama) "...because the logic of the lines traced from reality is as poor of aesthetic value as it is strict in consistency. " - Paolo Bozzi (Naive Physics - free translation) |
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"The facts gentlemen, and nothing but the facts, for careful eyes are narrowly watching." Isaac Asimov |
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It can't be the first, for obvious reasons. It can't be the second either, because in that case the photon would also inherit some of the electron's momentum (afterall, the electron wouldn't be still, would it?), and that would also cause scattering, as below. ![]() So how does a moving electron emit a photon so that the photon keeps going in exactly the same direction, taking it's own momentum into account? Edited to add diagram Edited again to add: I just realised the diagram does not show the effect of the second 'emission rebound' on the electron's velocity, but still the effect on the photon is the same. |
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If you or he could come up with an explanation for redshift that didn't require that we either ignore what we see in everyday life, or require that the rest of the universe is "different" than earth and required its own arduously rewritten laws to account for every difference needed to support Ashmore's theory, it might work. And, well, redshift is not a crutch. It is an observation, one of many, for which expanding space theory makes useful predictions, which are oddly enough borne out by supernova durations (in other words, it is a relativistic effect whatever the mechanism, not just a light phenomenon). Arp, Ashmore, and others don't predict relativistic effects, or allow for them for that matter. |
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I don't believe that Arp or Ashmore say anything about relativity at all. Their theories do not apply to relativity anymore than Darwin's.
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Delays in the rise and fall of brightness of supernova with redshift are indicative of a relativistic cause. Neither Arp nor Ashmore account for an increasing delay in rise and fall of supernova brightness with distance. They do not address ALL of the observations, just the ones they think they can pick at. The Arp and Ashmore redshift theories fail to account for observation, in critical ways. While expanding space does not account for all observation (accelerating expansion, for instance) it does *predict* crucial observations, such as time dilation in supernova brightness (it appears to take longer for a supernova to brighten then dim). To add to this, Ashmore's disagrees with local observation of plasma, light, and diffraction/diffusion. That is much more fundamental than a disagreement with mechanism of redshift; his disagrees with basic look-out-the-window observation of everyday phenomena. Arp's disagrees with itself, and makes no valuable predictions. In the end, it is Ashmore's and Arp's theories that have a single crutch upon which to stand: interpretation of redshift. Their mechanisms don't work unless all of physics up until now is wrong. And I mean ALL: you can't rely on shift in volume of an approaching then receeding object without calculating its intrinsic shift, based on some arbitrary and incalculable supposition. Also, your TV no longer works, fire turns into a disco-ball lightshow, and our eyes need to be corrected to see the sun as it appears rather than how Ashmore says we should see it. |
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I didn't dispute the numbers, but the method of seeing importance where there is none. For every 3 dollars I have, you give me 1 dollar a year. Is that the same as: you give me 1/3 a year? I don't think so. And if for every kg weight I have now, I'll gain a kilo every three year, that gives me 1/3 a year as well. Does that mean you can compare them? I guess you can, but I wouldn't try to find any significance in it, and this example (while of course fiction) is of two entities that have more to do with one another than Lyndon's.
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Knowledge is a curse, but ignorance is worse |
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Oh... sorry... as you were... :-s |
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Here is the correct proof of the theorem that Compton scattering of a photon without changing the direction results in no change in energy for the photon, that is, no redshift. We use a metric with signature +--- and units in which c=1 throughout.
Let k be the four-momentum of the photon and p be the four-momentum of the electron after scattering. Let k' and p' be the four-momenta of the photon and electron before scattering. Conservation of four-momentum (which means both energy and momentum conservation) implies: k + p = k' + p', or k - k' = p' - p . Square both sides, remembering that k^2 = k'^2 = 0 since they are photons and p^2 = p'^2 = m^2 where m is the mass of the electron and find: -2*k*k' = 2*m^2 - 2*p*p' . Now k may be decomposed into its time-like and space-like parts as k=k*(1, n), where is a unit vector in the direction of motion of the photon, and likewise p may be decomposed as p=m*gamma*(1, beta) where beta is v/c, that is, the velocity vector of the electron in units of c, and gamma = sqrt(1-beta^2). k' and p' may be expressed similarly. Written out this way the previous equation becomes: -2*k*k'*(1-n*n') = 2*m^2*(1 - gamma*gamma'*(1- beta*beta')). Without loss of generality we can work in the frame where the initial electron is at rest, that is beta' = 0 and gamma' = 1. We then have: -2*k*k'*(1-n*n') = 2*m^2*(1 - gamma). Now what happens if we make the assumption that there is no scattering of the photon, that is, that its direction remains unchanged? This means that n = n' and the left hand side of the equation is zero: 0 = 2*m^2*(1 - gamma), therefore gamma = 1 and beta = 0 for the scattered electron as well. In this frame that we have chosen this means that the four-momenta p and p' obey p = p' = m*(1, 0) so that p' - p = k - k' = 0. A four-vector that is zero in one frame is zero in all frames. The momentum and energy of the photon is thus unchanged by the scattering, therefore no redshift. QED.
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Microsoft is over if you want it. The bar has been lowered for the promotion of ATM ideas; the bar for the acceptance of ATM ideas must remain high. I now officially condemn CM's skits as smartaleck, ignorant, sophomoric, inflammatory and and a poor reflection on the level of discussion in BAUT. -- Bob Angstrom |
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This misses the point. Call it what you like; when you have an interaction between a photon and an isolated electron, you cannot get any energy transferred to the electron unless the photon changes direction. This follows from conservation of energy and momentum, just as Celestial Mechanic has shown. If the electron was bound to a nucleus, then you could have inelastic collisions with the electron jumping an energy level. But electrons by themselves don't have energy levels. In a thick plasma, you might involve other particles as well. But in the IGM, the electron is around about a meter away from any other particles. Cheers -- Sylas |
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You might be interested in what Ned Wright has to say about this: Quote:
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"Stupidity gets denser in a crowd" - Old Finnish saying. [My website and My BLOG] [Nimblebrain forums] |
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You can remove the units, but you cannot compare the two equations apart from the abstract (numerological) sense. In my example in my previous post, I gain 1/3 a year two times, but I don't gain 2/3 a year. Even though you can strip the units, you cannot do as if they don't exist or are meaningless. They limit you severely in what you can do with the results. I expressed my problems with his comparison of the two equations in the wrong way, but that doesn't change my fundamental problems with it. Thanks for the explanation though and the patience, as your attitude is a lot more helpful.
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Knowledge is a curse, but ignorance is worse |
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Being able to derive the accepted value for the Hubble constant confirms this. Quote:
Cheers, Lyndon |
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"Stupidity gets denser in a crowd" - Old Finnish saying. [My website and My BLOG] [Nimblebrain forums] |
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Do you see my point now? So, how do particles in a (ionized) gas oscillate about an equilibrium position? Quote:
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Have you read proper textbooks, like the references given by Mursula himself at the beginning of his lecture notes? Quote:
Plasma: light interacts with free electrons, which are charges (electric monopoles). In the former case, the electron is bound to a positive charge; in the latter, it is not. Ashmore's "analogy" is wrong because he equates atoms with free electrons. Quote:
Why don't you work out the average energy for Coulomb interaction in a typical IG plasma, and compare it to the average kinetic energy of an electron in that plasma? Quote:
Ashmore's out-of-context quotes? Have you read proper textbooks? My claim is based on my understanding of physics*, and I explained it extensively in this and the other thread. Quote:
20-page-long lecture notes? Did you read the textbooks Mursula references? Let's see what Feynman has to say: Quote:
If you did, you would realize that the harmonic motion you talk about is the result of the electric forces that keep an electron from flying away from the volume containing the plasma. Let's assume that your plasma is contained in a volume with well defined boundaries. What happens if an electron crosses those boundaries, leaving the volume. This volume would now have a net positive charge, which attracts the electron back into the volume. Imagine that the electron has enough momentum to overshoot the volume of the plasma, and crosses the boundary on the opposite side. Again the net positive charge would attract the electron back into the volume. This is the "simple harmonic motion" your citations talk about, and it is described in terms of macroscopic parameters such a the electron density. It occurs over length-scales comparable to the size of the volume occupied by the plasma, not on a microscopic scale. (I explained this in the other thread already.) *(which includes having studied and being tested on plasma-like behavior of electrons in metals, and a nice experiment in a teaching lab where we observed the effects of exciting plasmon in piece of metals)
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papageno "Why waste time learning, when ignorance is instantaneous?" - Hobbes (Calvin and Hobbes) "It's all about context!" - Vince Noir (The Mighty Boosh) "I've never heard of such a brutal and shocking injustice that I cared so little about!" - Zapp Brannigan (Futurama) "...because the logic of the lines traced from reality is as poor of aesthetic value as it is strict in consistency. " - Paolo Bozzi (Naive Physics - free translation) |
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Hadn't seen that one. I will have a look. |
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In the meantime let’s have a proper look at the situation. For absorption. By Newtonian mechanics. Photon frequency, f, wavelength λ, comes in and is absorbed by an electron initially at rest. Momentum, p = h/ λ = mv where m is the mass of the electron and v the recoil velocity. V = h/m λ . KE = mv^2/2 = h^2/2m λ^2. The plasma is in a state of thermal equilibrium where the rate at which it receives energy from the photons is equal to the rate at which it is given off as CMB (by bremstrahhlung). So lets work out the wavelength of a CMB photon produced by a redshifted photon of light (λ = 5x10-7 m). Energy = h^2/2m λ^2 = 9.6x10^-25J = hc/ λ tells us that the wavelength would be 0.21m ie in the microwave. To get CMb photons of wavelength 2.1mm we need the incoming photon to be in the UV. After the delay, the original photon is then re-emitted so let’s work out the energy lost on re-emission. Sylas feels that he has a monopoly on relativity so let’s work it out that way here – just for him. Consider our stationary electron of mass M(0), emitting a photon of energy Q (=hf). Let the recoiling electron have M’ (and rest mass M(0)’) and velocity v E = M(0)c^2 = M’c^2 + Q =E’ + Q p = 0 = M’v – Q/c = p’ – Q/c ie E’ = M(0)c^2 – Q cp’ = Q So (M(0)’c^2)^2 = (E’)^2 – (cp’)^2 = (M(0)c^2 – Q)^2 – Q^2 Or (M(0)’c^2)^2 = (M(0)c^2)^2 – 2M(0)c^2Q …………….(1) We can write M(0)’c^2 = M(0)c^2 - Q(0) where Q(0) is the total energy release. So (M(0)’c^2)^2 = (M(0)c^2)^2 – 2M(0)c^2Q(0) + Q(0)^2 Combining this with equation (1) gives Q = Q(0)(1 – Q(0)/2M(0)c^2) When we multiply out the bracket we can clearly see that the energy lost in recoil is Q(0)^2/2M(0)c^2 where Q(0) is the total energy available and approximately hf for the incoming photon (we can do it exactly but this is sufficient for here – the difference is that lost in absorption) Energy lost on re-emission = Q(0)^2/2M(0)c^2 = (hf)^2/2M(0)c^2 = h^2c^2/2M(0)c^2 λ^2 Or energy lost = h^2/2M(0) λ^2 Note that this is the same answer that we got with Newtonian mechanics and results in a second CMB photon being emitted on re-emission. So I don’t see how Sylas and CM feel it is impossible, it is just accepted physics. As a consequence, this Tired light theory not only explains the Hubble constant but also the CMB – plasma can emit Black body radiation. Cheers, Lyndon PS let me of any typos. |
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This is a consequence of the conservation of energy and momentum. Quote:
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If you really had a clue about the physics you are talking about, you would not need this excuse to avoid the issue. Quote:
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papageno "Why waste time learning, when ignorance is instantaneous?" - Hobbes (Calvin and Hobbes) "It's all about context!" - Vince Noir (The Mighty Boosh) "I've never heard of such a brutal and shocking injustice that I cared so little about!" - Zapp Brannigan (Futurama) "...because the logic of the lines traced from reality is as poor of aesthetic value as it is strict in consistency. " - Paolo Bozzi (Naive Physics - free translation) |
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See, that's the problem. Your idea would have DISTINCT effects on what we see currently. I.e.: According to your own summation of your postulated effect: I should be able to use an electron gun to focus a light beam. I can't do that. Please explain. Or get out of the pool. Quote:
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