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#281 |
Illuminator
Join Date: Oct 2009
Posts: 4,830
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computing lookback times from redshifts
References
Cappi's Equations Cappi's Equation (1) The Robertson-Walker metric can be written as ds2 = c2dt2 - R2(t) [ dr2 + Sk2(r) dΩ]where
On the other hand, Cappi's Sk(r) notation actually appears in the paper, and probably contributed to the divide-by-zero error in equation (6). Density Fractions Cappi writes Ωi for the first three fractions below, with i ranging over the subscripts in those three fractions, but his equations are easier to understand if written out (as in what follows).
ΩR is the radiation or relativistic mass density, as a fraction of the critical density. ΩΛ is the dark energy density, as a fraction of the critical density. Ωk = 1 - ΩM - ΩR - ΩΛ is the so-called curvature parameter. For flat space (k=0), Ωk = 0. For positively curved (closed, k=+1) space, Ωk < 0. For negatively curved (open, k=-1) space, Ωk > 0. Equations (4) and (6) are problematic, so I won't discuss them further outside of the following spoiler. Cappi's Equation (5) Unlike Cappi, I'm writing this out in full: E(z) = sqrt (Ωk(1+z)2 + ΩM (1+z)3 + ΩR(1+z)4 + ΩΛ)Cappi's Equation (7) The lookback time is t(z) = (1/H0) ∫0z dz' / [(1+z) E(z')] When faced with integrating the reciprocal of a square root of a polynomial in (1+z), I usually fall back on numerical integration. For several unrealistically simple models, however, it's easy to find a closed form for t(z). Lookback Time for Unrealistically Simple Models Completely Empty Universe with Negative Curvature With parameters
c t(z) = (c/H0) (z/(1+z)) Note, however, that space is negatively curved in this model. From Cappi's Ωk = 1 = k c2 / (HR)2and a bit of algebra, we get R0 = c / H0as the present-day radius of curvature for this model. With H0 approximately 70 km/s/Mpc, that radius of curvature is about 14 billion light years. If space were really that curved, we'd have noticed. Ωk=1 is hundreds of times more curvature than would be consistent with the Planck mission's observations:
Originally Posted by Wikipedia
Einstein-de Sitter Universe With parameters
Once again, applying a tiny bit of algebra and calculus to Cappi's equation (7) yields t(z) = (2/(3H0)) [1 - (1+z)-3/2]which implies t(z) < 2/(3H0) for all finite redshifts. With H0 ≈ 70 km/s/Mpc, that means the universe could not be more than about 9.33 billion years old. Radiation Universe With parameters
t(z) = (1 / (2 H0)) [z(1+z) / (1+z)2]implying such a universe could not be more than about 7 billion years old. Dark Energy Universe With parameters
t(z) = (1/H0) log (1+z)where log(1+z) is the natural logarithm of 1+z. As will be seen, that signifies a rapidly expanding universe. More Realistic Models of the Universe It looks as though the class of models considered in Cappi's paper best fit the universe in which we live with parameters such as these:
A Table of Lookback Distances This table shows distances obtained by multiplying the speed of light times lookback times for various models and red shifts, taking H0=70 km/s/Mpc. Distances are stated in billions of light years. Rows marked with (*) were calculated using the closed form solutions for simple models; all other rows were calculated using numerical integration. Code:
ΩM 0 1 0 0 0.2 0.3 0.4 ΩΛ 0 0 1 0 0.8 0.7 0.6 ΩR 0 0 0 1 0 0 0 Ωk 1 0 0 0 0 0 0 z = 0.1 1.27 1.24 1.33 1.21 1.31 1.30 1.29 z = 0.2 2.32 2.22 2.54 2.13 2.46 2.42 2.39 z = 0.3 3.22 3.03 3.66 2.85 3.49 3.42 3.35 z = 0.4 3.99 3.69 4.70 3.43 4.41 4.28 4.18 z = 0.5 4.66 4.25 5.67 3.89 5.22 5.05 4.90 z = 1 (*) 7.00 6.03 9.70 5.25 z = 1 7.00 6.03 9.70 5.25 8.19 7.73 7.36 z = 2 9.46 7.65 15.6 6.32 11.3 10.4 9.75 z = 3 10.7 8.29 19.7 6.67 12.7 11.6 10.8 z = 4 11.4 8.63 22.9 6.83 13.4 12.2 11.3 z = 5 11.7 8.70 25.1 6.80 13.6 12.3 11.4 z = 10 12.8 9.18 33.6 7.08 14.5 13.0 12.1 z = 20 13.4 9.34 42.6 7.13 14.9 13.3 12.3 z = 30 13.6 9.38 48.1 7.14 15.0 13.4 12.4 z = 40 13.7 9.40 52.0 7.14 15.0 13.5 12.4 z = 50 13.8 9.41 55.1 7.14 15.0 13.5 12.4 z = 100 13.9 9.43 64.6 7.14 15.1 13.5 12.4 z = 1000 14.1 9.43 96.7 7.14 15.1 13.5 12.5 z = 1000 (*) 14.0 9.33 96.7 7.00 z = 10000 (*) 14.0 9.33 128.9 7.00 |
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#282 |
Philosopher
Join Date: Aug 2002
Location: Denmark
Posts: 6,786
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W.D.Clinger, thanks for this huge and interesting post!
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#283 |
Illuminator
Join Date: Nov 2020
Posts: 3,318
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Cappi's paper isn't anything special. It just explains his cosmo calculator:
http://www.bo.astro.it/~cappi/cosmotools Which I made an interactive version of here: https://mikehelland.github.io/hubble...other/lcdm.htm
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Code:
if (Omega_L > 0. && Omega_k == 0.) { DC = ch0 * sumint(z1); DL = DC * z1 } if (Omega_L > 0. && Omega_k < 0.) { curv = Math.sqrt(-Omega_k) r = sumint(z1); DC = ch0 * Math.sin(r * curv) / curv DL = DC * z1 } if (Omega_L > 0. && Omega_k > 0.) { curv = Math.sqrt(Omega_k) r = sumint(z1); DC = ch0 * sinh(r * curv) / curv DL = DC * z1 } if (Omega_L == 0. && q0 > 0) { q0sq = q0 * q0 a = 1. - q0 + q0 * z + (q0 - 1.) * (Math.sqrt(2. * q0 * z + 1.)) DL = ch0 * a / q0sq DC = DL / z1 } if (Omega_L == 0. && q0 == 0) { DL = ch0 * z * (1. + z / 2.) DC = DL / z1 }
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FWIW, H0 never changes, so the 0 isn't actually necessary.
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Why do you use 70? Is it because FLRW doesn't hold up with the measured value?
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Does Hubble Tension Signal a Breakdown in FLRW Cosmology? https://arxiv.org/abs/2105.09790 |
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#284 |
Illuminator
Join Date: Oct 2009
Posts: 4,830
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I had not looked at Cappi's code or calculator at all. In the code you quoted, he has three separate calculations for the three cases, so his code does not actually match the equations in his paper. That is a good thing, because he messed up his equations (4) and (6) by trying to cram all three cases into a single equation.
H is the Hubble parameter, which change with time. H0 is the value of the Hubble parameter at the present day, which is a constant. The subscript is necessary so readers will know whether I'm talking about the Hubble parameter (which changes with time) or the Hubble constant. I used 70 km/s/Mpc because there is still a lot of uncertainty even in recent estimates of the Hubble constant, and 70 is a nice round number that lies within the range of uncertainty for many of those estimates. Furthermore, H0 ≈ 70 km/s/Mpc was implied by Mike Helland's computations in which his computed distances converge to 14 billion light years as the redshift z increases without bound. As for why Mike Helland assumed H0 ≈ 70 for his own calculations, but is now making an issue of my adoption of that same estimate, readers are free to draw their own conclusions. Cappi's equations are based upon straightforward FLRW models, and all calculations compatible with Cappi's equations and calculator (such as Mike Helland's own calculations) also assume FLRW models. As I have said, mainstream cosmologists are willing to consider effects that elaborate upon the basic FLRW models. One example of that willingness is the preprint cited by Mike Helland in his most recent contribution to this thread. |
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#285 |
Illuminator
Join Date: Nov 2020
Posts: 3,318
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Since the paper was merely documentation for his code, I think you should have.
I posted it in full in post 205: http://www.internationalskeptics.com...&postcount=205 Apparently you like to not read things and then judge them.
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Read. Think. Understand. |
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#286 |
Illuminator
Join Date: Oct 2009
Posts: 4,830
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Note: In several previous posts, I wrote t1 for the present day and t0 for the earlier time at which redshifted photons were emitted. That was inconsistent with the standard convention, in which t0 is the present day and t1 the earlier time at which redshifted photons were emitted. In what follows I am following the standard convention, in which t1 < t0.
Your very own equation contradicts you. Your equation relating distance to redshift is d = (c/H0) (z / (1+z))Equivalently, since you obtain the distance by multiplying the lookback time t by the speed of light c, t = (1/H0) (z / (1+z)) = t0 - t1The redshift z is defined by the equation 1 + z = a(t0) / a(t1) = λ(t0) / λ(t1) = f(t1) / f(t0)where
H = (da/dt1) / a(t1) Those three equations imply da/dt1 = H0 a(t0)(which is, surprisingly, a constant) which implies in turn that the value of the Hubble parameter is given by H(t1) = H0 (1 + z)where
H(t1) = H0 (1 + z)it is obvious that the value of the Hubble parameter changes over time in Mike Helland's model. I found it surprising that, according to Mike Helland's equation, the Hubble parameter was greater in the past and is decreasing at the present day. That is a consequence of Mike Helland's selection of a very peculiar FLRW model in which the universe is entirely devoid of matter, radiation, and dark energy, but space is strongly curved in the negative direction. It should be noted that I am not accusing Mike Helland of being aware that his equation implicitly assumed that model. He was aware that his equation relating distance to redshift assumed ΩM = ΩΛ = 0, which was already unrealistic, but his recent posts suggest he was at least as surprised as anyone else to learn that his equation assumed an FLRW model with a substantial amount of negative spatial curvature. |
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#287 |
Illuminator
Join Date: Nov 2020
Posts: 3,318
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#288 |
Illuminator
Join Date: Nov 2020
Posts: 3,318
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How is it this equation had never been discovered before?
I will tell you. WWII In the 1920's cosmological redshift was discovered. But it was very very small. Now, you could say an electron has -1 charge, and a proton has a +1 charge. Inherently, we would assume charges can be arbitrarily negative or positive. Let's say the same about redshifts. Red being positive and blue being negative is arbitrary. But it isn't. The entire domain in the positive equals, reversed, only equal up to -1. ![]() ![]() In the 1920's and 1930's this would have been prudent. The redshifts aren't that large. No one expected them to be z=1, much less z=10. In December of 1941, Hubble announced to the world that the expanding universe idea was wrong. But this was a week after Pearl Harbor. The word's most well known astronomer was assigned to a wind tunnel to study ballistics for the war effort. Years later, no one questioned the expanding universe, much less than quantification of redshift. The steady state universe was an expanding one, btw, if anyone thought that would be worth bringing up. |
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#289 |
Illuminator
Join Date: Oct 2009
Posts: 4,830
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In my previous post, I wrote:
I shouldn't have been surprised by that. As explained by Wikipedia, with italicized "not" as in the original:
Originally Posted by Wikipedia
This is madness: (ETA: In the context of that sentence, Mike Helland is saying the Hubble parameter H does not change over time in his model. In the past, Mike Helland has often appeared to be confused about the distinction between the Hubble parameter H and the Hubble constant H0, and it is possibly that he was confused when he wrote that sentence or is hoping the possibly deliberate ambiguity of "the Hubble term" will confuse others.) It is a mathematical fact that, when we combine the Helland equation d = (c/H0) (z/(1+z))with the two mainstream physics equations that define the redshift z and the Hubble parameter H, we find that the value of the Hubble parameter changes with time in whatever model Mike Helland thinks he's using. We don't need to discuss the details of Mike Helland's model, because the time-varying Hubble parameter follows directly from the Helland equation and the mainstream definitions of z and H. By saying "The Hubble term does not change in my model", Mike Helland is telling us that he rejects at least one of these three equations:
By rejecting one or more of those equations, Mike Helland is abandoning at least one of these three claims:
Because claims 1 and 2 are tenable in that sense, Mike Helland could have declared victory. With claim 3, however, his second claim collapses. Regardless of the details of Mike Helland's model, claims 1 and 2 support a mathematical proof that claim 3 is false. Mike Helland doesn't have many options here. He can abandon claim 1, he can abandon claim 2, or he can abandon claim 3. If he persists in claiming all 3, then Mike Helland is arguing with high school algebra and calculus. "Matter doesn't [a]ffect redshift" is not consistent with mainstream physics. It seems therefore that Mike Helland is abandoning his claim 2 above. Despite his recent repetitions of claim 2: |
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#290 |
Illuminator
Join Date: Nov 2020
Posts: 3,318
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2 and 3. Since space isn't expanding in my model, anything with the scale factor is abandoned.
My claim was that my equation predicts the same lookback times as an FLRW model where gravity doesn't counteract redshifts. A little context would be helpful here. In 1915 Einstein came up with general relativity. It was around 1919 that he applied the theory to the universe as a whole. At the time, Babe Ruth played for the Red Sox, and galaxies hadn't been discovered yet. So he was applying GR to a field of stars. He noted this would collapse. Where does it collapse? Toward us? Seems a bit anti-Copernican. In any case, we're making an assumption here. Let me elaborate. Imagine you're watching a play, and the actors say their lines and make their motions. Now imagine the same play where the stage is expanding, and the actors are all moving away from each other. Do the actors still say their lines and move about as they did before? Or do they realize they are moving away from each other, and then move toward each other to try to stay where they were? Applying GR to the universe as a whole assumes the latter. Space isn't just expanding, but the things in it are counteracting the expansion. If we assume the former, that space expands, and the actors (which include gravity and electromagnetism) play their roles with this new dynamic of spacetime rather than against it, you get a universe that always expands and will never collapse (negative curvature). And you eliminate the need for dark energy entirely. In FLRW models, gravity does counter act redshifts, assuming the matter density is greater than zero. I'm not advocating any FLRW model. In those models, we don't exist:
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Here's a quick recapp of my position. Redshift is traditionally quantified as: 1+z = Eemit / EobsAnd its relation to distance is: d = cz / H0But this is only valid when z<<1 (much less than one). So we can invert it: 1+b = Eobs / EemitAnd then: d = -bc / HSince 1+b=1/(1+z), then b=1/(1+z)-1=-(z/(1+z)), so: d = z/(1+z) * c/H This stands separate from GR and FLRW. But the lookback times are identical to FLRW when the matter density of the universe doesn't counteract its expansion. |
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#291 |
Illuminator
Join Date: Oct 2009
Posts: 4,830
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We have witnessed the collapse of Mike Helland's claim that Helland physics is consistent with mainstream physics.
Mike Helland has abandoned claim 2: By rejecting two of the most important mainstream equations concerning the relationship between redshift and the expansion of space, Mike Helland has abandoned his claim that Helland physics is consistent with mainstream physics. I'm glad we were finally able to put an end to that charade. |
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#292 |
Illuminator
Join Date: Nov 2020
Posts: 3,318
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#293 |
Illuminator
Join Date: Nov 2020
Posts: 3,318
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I did find this:
![]() https://arxiv.org/abs/astro-ph/9306002 I think what's interesting about that is: 1 + z = Eemit / EobsBut, if they had chose to quantify redshift as negative blueshift, they would have found: 1 + b = Eobs / EemitI think the best way to quantify it though would be as an energy scalar Q: Q = Eobs / EemitThe 1+z and 1+b formulas give valid result between -1 and infinity. On the other hand Q is always positive, and is directly related to the energy of a photon. Seems to more closely follow nature than arbitrarily preferring redshift or blueshift to be positive or negative. |
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#294 |
Illuminator
Join Date: Oct 2009
Posts: 4,830
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correcting an editing error
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#295 |
Illuminator
Join Date: Nov 2020
Posts: 3,318
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#296 |
Illuminator
Join Date: Oct 2009
Posts: 4,830
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If you'd been paying attention, you'd have read this ten days ago: And you'd have read this five days ago: And just last night, you could have found the excerpt quoted immediately above by following the link in this paragraph you quoted: ETA: As I noted earlier this morning, the highlighted parameter should have been Ωk. |
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#297 |
Illuminator
Join Date: Nov 2020
Posts: 3,318
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#298 |
Illuminator
Join Date: Oct 2009
Posts: 4,830
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Mike Helland needs some help with arithmetic.
No. I am comparing the observed value of Ωk = 0.0007±0.0019 to your assumption that Ωk = 1. 0.0007 + 0.0019 = 0.0026 0.0007 - 0.0019 = -0.0012 1 / 0.0026 ≈ 384.6 1 / -0.0012 ≈ -833.3 To be clear, I am not accusing you of being aware that your Helland equation, like the values you calculated using Cappi's calculator with ΩM = ΩΛ = ΩR = 0, assumed Ωk = 1. To the contrary, I think it's pretty clear that you have been more or less completely clueless concerning Cappi's paper (which you cited repeatedly and quoted) and concerning Cappi's calculator (which you relied upon repeatedly, as its agreement with your Helland equation was the entire basis for your claim that your equation matched calculations based on mainstream physics). You didn't realize you were assuming Ωk = 1, so you didn't realize you were assuming a model with hundreds of times more curvature than is consistent with observation. But your cluelessness does not excuse the fact that your equation and calculations assumed a degree of negative curvature that is hundreds of times greater than would be consistent with observations made by the Planck mission. |
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#299 |
Illuminator
Join Date: Nov 2020
Posts: 3,318
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That's pretty funny. If you use 0.0007 its thousands of times off. And if you use 1 * 10-45 its 45 orders of magnitude off, and then there's also a vertical asymptote in the domain too, which is actually what its expected to be. That's why I wondered about the hundreds thing. It's a pretty arbitrary claim.
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Here is an expanding universe with no matter to counteract it (red line). ![]() That's Pure Expansion. Here's the same universe with matter and gravitation that counteracts expansion (red line): ![]() That's Expansion + Attraction. We know the universe must be older than 9 billion years, so that's clearly wrong. We can add dark energy to sort of right the wrong there (red line): ![]() That's Expansion + Attraction + Repulsion. In order, you have negative curvature, then positive curvature, and then none (or very very little). However, since my equation (black line) is not based on GR, and since I doubt the universe is expanding, and I doubt that gravity affects redshifts, and thus I doubt the need for dark energy, you get this universe: ![]() This universe has light that redshifts. No curvature or FLRW necessary. (edit: and I don't mean it has zero curvature. I'm mean the concept is absent in this treatment of redshift.) As distance measurements continue to advance further out, the slight differences between the predictions of my equation, and those of the mainstream LCDM (ΩM=0.3 and ΩΛ=0.7) will be testable by observation. I get that most people believe in the CMB because its evidence of the big bang. But since I doubt all that, why should I believe it? Do you know specifically how measurements of the CMB are made, and how you arrive at Ωk = 0.0007±0.0019? Seems about akin to looking at the coals of campfire, and proclaiming you can tell what stories were told around it. |
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#300 |
Illuminator
Join Date: Oct 2009
Posts: 4,830
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My statement was conservative, not arbitrary. The Ωk = 1 you assumed when using Cappi's calculator is at least several hundred times any curvature that would be consistent with the Planck observations.
It is the spatial expansion predicted by mainstream physics for a universe totally devoid of matter and energy, but with negative spatial curvature that is hundreds of times (at least!) greater than would be consistent with observations. It is not the spatial expansion predicted by Helland physics, because Helland physics rejects the concept of spatial expansion. That's Helland physics. As indicated by the phrases I highlighted both above and below, Helland physics is based on one person's personal incredulity and ignorance of mainstream physics, including his rejection of general relativity. You are the world's foremost authority on Helland physics, so you can make up whatever stories you like. You have yet to suggest a reason for anyone else to pay the slightest attention to Helland physics. |
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#301 |
Illuminator
Join Date: Nov 2020
Posts: 3,318
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I don't reject GR.
GR predicts an accurate orbit for Mercury and GPS satellites, using metrics that are not FLRW. When Einstein and Friedmann were applying GR to the universe as a whole, galaxies had not yet been discovered. It was a field of stars. For FLRW to work, there can be no empty space and there can be no bodies (rocks, planets, stars, galaxies, etc). Clearly it does not represent reality.
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https://en.wikipedia.org/wiki/Lambda...del#Challenges Code:
5.1 Lack of detection 5.2 Violations of the cosmological principle 5.2.1 Violations of isotropy 5.2.2 Violations of homogeneity 5.3 El Gordo galaxy cluster collision 5.4 KBC void 5.5 Hubble tension 5.6 S8 tension 5.7 Axis of evil 5.8 Cosmological lithium problem 5.9 Shape of the universe 5.10 Violations of the strong equivalence principle 5.11 Cold dark matter discrepancies 5.11.1 Cuspy halo problem 5.11.2 Dwarf galaxy problem 5.11.3 Satellite disk problem 5.11.4 High-velocity galaxy problem 5.11.5 Galaxy morphology problem 5.11.6 Fast galaxy bar problem 5.11.7 Small scale crisis 5.12 Missing baryon problem 5.13 Unfalsifiability |
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#302 |
Penultimate Amazing
Join Date: Jun 2003
Posts: 53,389
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__________________
"As long as it is admitted that the law may be diverted from its true purpose -- that it may violate property instead of protecting it -- then everyone will want to participate in making the law, either to protect himself against plunder or to use it for plunder. Political questions will always be prejudicial, dominant, and all-absorbing. There will be fighting at the door of the Legislative Palace, and the struggle within will be no less furious." - Bastiat, The Law |
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#303 |
Illuminator
Join Date: Oct 2009
Posts: 4,830
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You don't realize you're rejecting general relativity. Not realizing that you are rejecting GR is not the same as not rejecting GR.
Yes, the Schwarzschild model is an exact solution of the Einstein field equations, just as the FLRW models are exact solutions of those same equations. Scientists understand that a model that serves as a suitable idealization for one set of circumstances may not be a suitable idealization for other sets of circumstances. Scientists understand that the FLRW models are idealized models, and are quite willing to consider perturbations, extensions, and other tweaks that may improve the usefulness of those models. More generally:
Originally Posted by W.D.Clinger
Here are a couple of the more obvious tests we might apply when trying to decide between mainstream and Helland physics:
Real scientists welcome challenges, and (as I stated above) are quite willing to consider perturbations, extensions, and other tweaks that may improve the usefulness of idealized models that succeed in predicting/explaining the gist of observed phenomena but may fall short when it comes to more specialized details. With regard to the challenges cited above, Helland physics has nothing to offer. Mike Helland has yet to articulate any reason for anyone to pay the slightest attention to Helland physics. |
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#304 |
Illuminator
Join Date: Nov 2020
Posts: 3,318
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The general theory of relativity seems to be a bit special in this regard, that it's not a single equation, like Newton's law of gravity, but a 4 dimensional Pythagorean theorem in non-Euclidean geometry that acts almost like an operating system given a coordinate system and metric.
GTR itself does not rely on any particular metric, including FLRW, being accurate representations of reality.
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Being in disagreement with observation is. And LCDM has that in spades. |
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#305 |
Illuminator
Join Date: Nov 2020
Posts: 3,318
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Ok. So what scale?
https://en.wikipedia.org/wiki/Lambda...ical_principle The Giant Arc is 1 billion parsecs long. So I'm guessing more than that?
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But the equation that W.D.Clinger has dubbed the Helland equation does not change the speed of light. |
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#306 |
Illuminator
Join Date: Oct 2009
Posts: 4,830
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No one with any serious knowledge of science in general, or general relativity in particular, would have written this:
Maxwell's equations, as taught in freshman physics, consist of four equations:
So Mike Helland is asserting his ignorance of Maxwell's equations as well as his ignorance of the fundamental equation(s) of general relativity. As for the idea that Einstein's field equations are "a 4 dimensional Pythagorean theorem in non-Euclidean geometry", well, no. Even apart from the fact that Pythagoras died more than a century before Euclidean geometry became a thing, and a couple of thousand years before non-Euclidean geometry was recognized as legitimate, Einstein's field equations are not a theorem of any branch of mathematics. Einstein's field equations express a theory about the real world, not a theorem that can be proved from geometrical axioms. |
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#307 |
Illuminator
Join Date: Nov 2020
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#308 |
Illuminator
Join Date: Nov 2020
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Maxwell had 20 equations. Heaviside made them into 4.
But go on. Tell me I am ignorant over and over.
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#309 |
Illuminator
Join Date: Oct 2009
Posts: 4,830
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What part of "as taught in freshman physics" are you failing to understand?
So says the originator and, so far as I can tell, sole advocate of Helland physics. Until evidence for such claims is provided, it is fair to note that the sole advocate of Helland physics has yet to articulate any reason for anyone to pay the slightest attention to Helland physics. |
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#310 |
Illuminator
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#311 |
Illuminator
Join Date: Nov 2020
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For context, what you refer to Helland physics is something I came up with a month ago and introduced in this thread:
http://www.internationalskeptics.com...0&postcount=81 As for the problems with LCDM and how "Helland physics" resolves them (excluding dark matter issues):
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The size of things is a non-issue for my hypothesis.
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In my model, the CMB isn't what LCDM says it is, and it does not tell us the rate of expansion. So ~74 km/s/Mpc, the measured rate of expansion, is the only valid one, and thus there is no tension.
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My model doesn't predict how much H, or He, or Li is around. It predicts redshifts and distances and lookback times. So the chemical make up of the universe is a non-issue.
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#312 |
Illuminator
Join Date: Oct 2009
Posts: 4,830
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I was referring to your claim, quoted above, that "Helland physics...resolves nearly every one of those issues except those related to dark matter."
But that claim wasn't very specific, so I guess you have a point. Not the sort of point in which anyone should take pride, but I guess any kind of point would be a start. For context, conspiracy theorists and crackpots like to pretend their "theory" is the only viable alternative to the windmill they're assaulting, so they gleefully point to every flaw in the finishing of that windmill as if that flaw were evidence for their "theory". Mike Helland is doing a lot of that in what I'm quoting below, but he also goes beyond the usual nonsense by ignoring the purpose or, at times, the very existence of the windmill. In his remarks I have highlighted in blue, Mike Helland wants us to think Helland physics is superior to mainstream physics because Helland physics doesn't even try to deal with empirical facts that have been predicted or explained, however imperfectly, by mainstream cosmology. We don't often see people come right out and say "my theory is better because it has so little to say", but that's pretty much what Mike Helland is saying here. |
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#313 |
Illuminator
Join Date: Nov 2020
Posts: 3,318
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Ok.
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I said the distance relationship is" d = -(1/(1+z)-1) c/H0You said I should write it as: d = z/(1+z) c/H0Which means to me, that's not the Helland equation. That's the Helland/Clinger equation. Agree? |
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#314 |
Philosopher
Join Date: Aug 2002
Location: Denmark
Posts: 6,786
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Mike Helland, you blame Lambda-CDM for not being able to predict certain variations in the CMB, but Helland physics ignores the CMB completely. How can that be better?
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Steen -- Jack of all trades - master of none! |
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#315 |
Illuminator
Join Date: Nov 2020
Posts: 3,318
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Not sure I get this. LCDM make predictions. They aren't all right.
That's an established fact. Imagine you ordered a glass of water. When it arrived, the server tipped it over and spilled half of it on your lap. Then poked a few holes in the bottom of the cup before you received it. That's the CMB (excess energy at the beginning) and redshift (photons leaking energy). I doubt that's real. The photons redshift (empirical fact) and the energy lost is observed as the CMB. |
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#316 |
Philosopher
Join Date: Aug 2002
Location: Denmark
Posts: 6,786
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Steen -- Jack of all trades - master of none! |
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#317 |
Schrödinger's cat
Join Date: May 2004
Location: Malmesbury, UK
Posts: 15,323
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It's not hard to grasp.
1. LCDM makes predictions about the CMB, some of which (though not all) have proved correct 2. Helland physics makes no predictions about the CMB whatsoever That makes LCDM the superior description of the universe. If you could use Helland physics to make more accurate predictions about the CMB than LCDM does you might have something worth examining more closely. But you can't, so you don't. |
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"If you trust in yourself ... and believe in your dreams ... and follow your star ... you'll still get beaten by people who spent their time working hard and learning things" - Terry Pratchett |
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#318 |
Illuminator
Join Date: Nov 2020
Posts: 3,318
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#319 |
Illuminator
Join Date: Nov 2020
Posts: 3,318
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#320 |
Illuminator
Join Date: Nov 2020
Posts: 3,318
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