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Old 6th April 2021, 10:02 PM   #1
Lukraak_Sisser
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I don't think space is expanding Part II

Mod Info Continued from here: http://www.internationalskeptics.com...d.php?t=348218 As usual the split point is arbitrary and participants are free to respond to posts from the original thread.
Posted By:Agatha



Originally Posted by Mike Helland View Post
If you think the redshifts tell the story of how the universe started and how it will end, nothing I say will ever change your mind.

It's not just an observed phenomenon to you. It's a creation story.
I always find it interesting how those with alternative models accuse others of dogma and religion, while they are the ones that refuse to accept that their model might be wrong and ignore all criticism.
The fallback position of those who cannot defend themselves.

Mike, your theory is wrong.
Maybe, just maybe it is possible that expanding space is also wrong, but even if it is (and no observation so far has shown it to be), your theory will never replace it, as it fails at every basic level.
If it can be taken apart on a website by people just spending some of their free time on it, it will be shattered the moment you try to actually engage scientists.

To put it in a programming analogy, you are the equivalent of a manager who coded a few lines of BASIC when he was young, who now tells the lead programmer of his company that his brilliant simple solution can be used to optimize the whole IT structure of the company, while ignoring all input from those that actually know what they are talking about.

Last edited by Agatha; 7th April 2021 at 01:39 PM.
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Old 6th April 2021, 10:03 PM   #2
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Ps. I am not implying that posters here are not scientists, but rather that the discourse here is far more cordial than actually trying to get something published.
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Old 6th April 2021, 10:05 PM   #3
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Exclamation Some "dt" idiocy and adds ignorance of mathematics to his pit of ignorance

Originally Posted by Mike Helland View Post
Well, doing it the calculus way, you're looking for the limit as dt approaches zero.

But using small values of dt in a computer program will approximate it just fine.
7 April 2021: Some "dt" idiocy and adds ignorance of mathematics to his pit of ignorance

The "calculus way" is to actually solve the integral! There is also numerical integration which is good at approximating integration over smooth functions. There is even https://www.wolframalpha.com/ for those who do not know calculus.
Guessing at a value of delta-t (which is not dt) and vaguely hoping that it will give the correct integration is abysmal mathematics.
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Old 6th April 2021, 10:29 PM   #4
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Exclamation Mike Helland's new deep ignorance that we must actually see things before they exist

Originally Posted by Mike Helland View Post
The redshift distance relation is stated in Hubble's law, v=H0D.

That seemed to be fine from 1929 to 1998, when the acceleration of the redshifts was firmly established.
Some history followed by repeating his ignorant fantasies.
v=c-HD has nothing to do with Hubble's law. Galaxies close to us are not moving away close to the speed of light ! v is not the v in Hubble's law. H his nothing to do with Hubble. That equation is his seemingly abandoned changing speed of light fantasy that does not cause redshift. The frequency of light does not depend on speed.

7 April 2021: Mike Helland's new deep ignorance that we must actually see things before they exist .
We have never seen dark energy. Whether is causing the acceleration of the expansion of the universe has properties that ensure we cannot see it! But we can measure what it does. We can see that the effect has been in GR since its beginning (a non-zero cosmological constant).
There are other examples such as neutrinos, quarks, black holes, and the hot dense state of the early universe!

7 April 2021: Mike Helland's ignorance about the actually "observed" inflation and dark energy.

10 March 2021: Mike Helland makes a high school science error (Therefore "c - c/(1+HD)2" is a high school science error).
10 March 2021: The total idiocy that he can change the units of Hubble's constant!
21 March 2021: A deeply ignorant "v = c/(1+ D/H}2 fantasy from Mike Helland (even ignorant about his own fantasies !).
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Old 7th April 2021, 02:03 AM   #5
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Originally Posted by Reality Check View Post
7 April 2021: Mike Helland's new deep ignorance that we must actually see things before they exist .
We have never seen dark energy. Whether is causing the acceleration of the expansion of the universe has properties that ensure we cannot see it! But we can measure what it does.
And therefore the awards are deserved.
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Old 7th April 2021, 02:15 AM   #6
Mike Helland
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Originally Posted by Lukraak_Sisser View Post
I always find it interesting how those with alternative models accuse others of dogma and religion, while they are the ones that refuse to accept that their model might be wrong and ignore all criticism.
The fallback position of those who cannot defend themselves.

Mike, your theory is wrong.
Maybe, just maybe it is possible that expanding space is also wrong, but even if it is (and no observation so far has shown it to be), your theory will never replace it, as it fails at every basic level.
If it can be taken apart on a website by people just spending some of their free time on it, it will be shattered the moment you try to actually engage scientists.

To put it in a programming analogy, you are the equivalent of a manager who coded a few lines of BASIC when he was young, who now tells the lead programmer of his company that his brilliant simple solution can be used to optimize the whole IT structure of the company, while ignoring all input from those that actually know what they are talking about.
Let's say there's a galaxy observed with z=2.

Show me how you calculate it's distance.
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Old 7th April 2021, 02:55 AM   #7
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Originally Posted by Mike Helland View Post
If you think the redshifts tell the story of how the universe started and how it will end, nothing I say will ever change your mind.

It's not just an observed phenomenon to you. It's a creation story.
On their own, red shifts donít. They are just one piece of the puzzle.

But for some reason, itís the only piece you want to play with. And nothing anyone has said has gotten through to you. You refuse to learn.
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Old 7th April 2021, 01:45 PM   #8
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Crisis in a cosomology thread!

This thread has become long so I have opened a continuation thread here: http://www.internationalskeptics.com...d.php?t=350705
Posted By:Agatha
Contrary to this observation, I don't think the thread is expanding. Rather, I subscribe to a "tired idea" hypothesis, which predicts that the ideas will get blurrier and blurrier as time goes on. And this is exactly what is observed.
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Old 7th April 2021, 02:26 PM   #9
Reality Check
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Originally Posted by Mike Helland View Post
And therefore the awards are deserved.
Some nonsense in reply to 7 April 2021: Mike Helland's new deep ignorance that we must actually see things before they exist .

Awards are deserved when people establish the existence of something with conclusive physical evidence even if we cannot see it directly in instruments.
The discoverers of dark energy got the Nobel Prize a decade after the 1998 discovery. That discovery did not spring out of nowhere. Scientists knew in the 1980's that GR without a cosmological constant did not match a series of observations. In 1987 the Supernova Cosmology Project was started. 11 years later we get the 1998 discovery by two independent groups. The other group was the High-Z Supernovae Search Team including Adam Riess and Brian Schmidt.
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Old 7th April 2021, 02:31 PM   #10
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Exclamation An irrelevant and ignorant distance to a galaxy at z = 2 question from Mike Helland

Originally Posted by Mike Helland View Post
Let's say there's a galaxy observed with z=2.

Show me how you calculate it's distance.
8 April 2021: An irrelevant and ignorant distance to a galaxy at z = 2 question from Mike Helland.
Lukraak_Sisser wrote about the dogma and religion of those with alternative models. Scientists know what science is and that is is not curve fitting with no science. Scientists know science and tend to abandon their invalid ideas by themselves. Scientists are in a community of scientist who review each others idea. Scientists are confident and brave enough to publish their ideas to be criticized by their peers and many others.
We have an enormous body of evidence that the universe is expanding which Mike Helland still cannot understand ! We plug z = 2 into the model and get the distance. Otherwise there is no way to determine its distance from its redshift.
This post shows Mike Helland insisting on not learning about cosmology.
Quote:
If you think the redshifts tell the story of how the universe started and how it will end, nothing I say will ever change your mind.

It's not just an observed phenomenon to you. It's a creation story.
Redshift does not tell anyone how the universe started. It just says that the universe is expanding. No one can observe the extremely early universe, e.g. inflation starting at ~ 10−36 seconds. The best we can do is get to ~1 second with the cosmic neutrino background. The Big Bang theory does not include any creation (if any!) of the universe.

Last edited by Reality Check; 7th April 2021 at 02:46 PM.
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Old 7th April 2021, 05:36 PM   #11
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Originally Posted by Reality Check View Post
We plug z = 2 into the model and get the distance. Otherwise there is no way to determine its distance from its redshift.
I'd like to see someone try to do that, using dark energy.

Here's my version:



25 * (Math.sqrt(1+2) - 1) = 18.3 Gly

The lamda-CDM model predicts just south of that.

https://www.wolframalpha.com/input/?...rameter+%3D+74
implied age of universe | 13.1 billion years
time ago (lookback time) | 9.88 billion years
time since big bang | 3.19 billion years
distance (comoving) | 16.4 billion ly (light years)
5020 Mpc (megaparsecs)
1.55◊10^23 km (kilometers)
9.62◊10^22 miles
fraction of total observable radius | 0.368
scale factor | 0.333 ◊ current value
(using additional parameters from 5-year WMAP data)
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Old 7th April 2021, 06:46 PM   #12
Reality Check
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Exclamation Mike Helland writes idiocy about the calculation of distance from z

Originally Posted by Mike Helland View Post
I'd like to see someone try to do that, using dark energy....
8 April 2021: Mike Helland writes idiocy about the calculation of distance from z.

Deep ignorance about even the value of the Hubble constant. The Hubble constant is not 74. It is either around 67 or 73.

He did a calculation at wolframalpha where there are options to include dark energy density, matter density and radiation density. One click adds the measured density parameters, Another click computes!
https://www.wolframalpha.com/input/?...rameter+%3D+73 with dark energy density = 0.726, matter density = 0.253, radiation density = 0.0000839708.

Comoving distance = 16.8 billion light years for 73, 18.3 billion light years for 67.

8 April 2021: Ignorance of basic mathematics or science: 18.3 is not close to 16.5 and debunks his equation !
His value of 18.3 billion light years is nowhere near the calculated value of 16.5 billion light years for a Hubble constant of 74.
If he had done proper curve fitting to the data then the values should be similar. They are not. I expect he has done no curved fitting at all! He has made up a formula. Seen that it sort of matches the data by eye and has the ignorant idea that his curve fits the data. He has just illustrated that is an ignorant idea.

Mike Helland's hypocrisy of using the Lambda-CDM model that he states is wrong ! The title of this thread is "I don't think space is expanding Part II". The Lambda-CDM model is of an expanding universe with two of the unseen things he does not believe in - dark energy and dark matter. He explicitly stated that he believes dark energy does not exist so he would set dark energy = 0. He has not mentioned dark matter yet but this is a person who wrote he cannot believe in unseen things.

Last edited by Reality Check; 7th April 2021 at 06:51 PM.
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Old 7th April 2021, 06:50 PM   #13
Mike Helland
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Originally Posted by Reality Check View Post
8 April 2021: Mike Helland writes
He did a calculation at wolframalpha where there are options to include dark energy density, matter density and radiation density. One click adds the measured density parameters, Another click computes!
Yes.

Now how do you do that computation?

Without using wolfram alpha.

Quote:
8 April 2021: Ignorance of basic mathematics or science: 18.3 is not close to 16.5 and debunks his equation !
His value of 18.3 billion light years is nowhere near the calculated value of 16.5 billion light years for a Hubble constant of 74.
That is correct.

These are predictions.

Your model has the data taking a hard right.

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Old 7th April 2021, 07:08 PM   #14
Reality Check
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Exclamation An ignorant and idiotic "how do you do that computation?" question from Mike Helland

Originally Posted by Mike Helland View Post
Yes....
8 April 2021: An ignorant and idiotic "how do you do that computation?" question from Mike Helland.
Repeating his ignorance of cosmology. He should have learned physics and cosmology before making up his fantasies. I do not need to do the computation. It is found in the textbooks and other sources he never bothers to learn.

8 April 2021: Mike Helland writes idiocy about the calculation of distance from z.
An idiotic "Yes" to 8 April 2021: Ignorance of basic mathematics or science: 18.3 is not close to 16.5 and debunks his equation !

8 April 2021: A possibly lying graph with "Lambda-CDM" dots from a person ignorant of astronomy and especially cosmology!
No citation to the source of those "Lambda-CDM" dots. A fantasy about his made up formula giving a prediction. A scientific prediction uses a scientific theory to make testable, falsifiable predictions.
At best what he has is a "forecast" - an extension of a curve that may or may not obey the rules that govern the data it fits. A hypothetical example from the current crisis. Back in March 2020 with the first Covid-19 cases, an ignorant person might have fitted a curve to the data and perhaps come to the consolation of tens of millions of deaths in the next year. They would have ignored the real world where health care measures and eventually vaccines would take the edge off a rapidly rising curve.

Last edited by Reality Check; 7th April 2021 at 07:20 PM.
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Old 7th April 2021, 07:12 PM   #15
Mike Helland
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Originally Posted by Reality Check View Post
8 April 2021: An ignorant and idiotic "how do you do that computation?" question from Mike Helland.
Repeating his ignorance of cosmology. He should have learned physics and cosmology before making up his fantasies. I do not need to do the computation. It is found in the textbooks and other sources he never bothers to learn.

8 April 2021: Mike Helland writes idiocy about the calculation of distance from z.
An idiotic "Yes" to 8 April 2021: Ignorance of basic mathematics or science: 18.3 is not close to 16.5 and debunks his equation !

8 April 2021: A possibly lying graph with "Lambda-CDM" dots from a person ignorant of astronomy and especially cosmology!
No citation to the source of those "Lambda-CDM" dots.
Wolfram alpha.

If you can show me how to compute them myself, that'd be cool.
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Old 7th April 2021, 07:22 PM   #16
theprestige
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Originally Posted by Mike Helland View Post
Wolfram alpha.

If you can show me how to compute them myself, that'd be cool.
One of the points made repeatedly in this thread is that until you learn the body of knowledge that supports your being able to compute them yourself, you are not yet ready to do the kind of physics you are attempting here.
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Old 7th April 2021, 07:39 PM   #17
Reality Check
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Exclamation The persistent ignorance that shows it is useless to try to educate Mike Helland

Originally Posted by Mike Helland View Post
...If you can show me how to compute them myself, that'd be cool.
We know it is useless explaining anything to Mike Helland since this thread at least has shown it is a waste of time. He will ignore it and repeat his debunked and ignorant fantasies yet again.
An easy to understand example. The CMB has physical features that show it must be cosmological. He has known this for many weeks. He still repeats a ignorant fantasy that the CMB is emitted from photons (starlight) redshifting.
I suspect that his website still has the ignorance that was corrected weeks ago, e.g. the stupidity of photons leaving a null geodesic when by definition that is what they always follow!

The pit of ignorance, errors and fantasies that Mike Helland is digging himself into gets deeper.
29 March 2021: Mike Helland states his "decelerating photon" fantasy violates the laws of physics.
29 March 2021: Mike Helland starts a new "expanding time hypothesis" fantasy.
30 March 2021: "I am thinking of the CMB as the radiation itself." idiocy from Mike Helland.
31 March 2021: Mike Helland persists in his fantasies about the CMB when he knows it is cosmological.
31 March 2021: "The energy budget of the expanding universe is quite, um, nonsensical" + "excess energy from the beginning of time" fantasies from Mike Helland.
31 March 2021: "This predicts mature galaxies in the "early" universe" idiocy when he has no predictions !
31 March 2021: "inflation has the entire universe popping into existence" ignorance from Mike Helland.
31 March 2021: "What value of H0 gives you 13.8 billion years" ignorance from Mike Helland
6 April 2021: Some ignorant nonsense about a galaxy with z=11 and a cartoon
6 April 2021: After weeks, Mike Helland is still abysmally ignorant about photons and the CMB !
6 April 2021: An irrelevant display of ignorance and gibberish about GR from Mike Helland.

7 April 2021: Mike Helland's ignorance about the actually "observed" inflation and dark energy.
7 April 2021: Mike Helland's new deep ignorance that we must actually see things before they exist .
7 April 2021: Deeper into his pit of fantasy and ignorance with "The current theory is busted."

8 April 2021: An ignorant and idiotic "how do you do that computation?" question from Mike Helland.
8 April 2021: Mike Helland writes idiocy about the calculation of distance from z.
8 April 2021: Ignorance of basic mathematics or science: 18.3 is not close to 16.5 and debunks his equation !
8 April 2021: A possibly lying graph with "Lambda-CDM" dots from a person ignorant of astronomy and especially cosmology!

Last edited by Reality Check; 7th April 2021 at 07:50 PM.
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Old 7th April 2021, 07:39 PM   #18
Mike Helland
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Originally Posted by theprestige View Post
One of the points made repeatedly in this thread is that until you learn the body of knowledge that supports your being able to compute them yourself, you are not yet ready to do the kind of physics you are attempting here.
Well, this is simple enough:

25 * (Math.sqrt(1+2) - 1)

Have you personally computed the distance to galaxies using dark energy parameters?

Has anyone here?
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Old 7th April 2021, 07:50 PM   #19
Reality Check
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Exclamation Repeats his demand that we personally do a calculation

Originally Posted by Mike Helland View Post
Has anyone here?
Repeats his demand that we personally do a calculation when he knows wolframalpha exists ! And that the calculation debunks his made up formula.
8 April 2021: Ignorance of basic mathematics or science: 18.3 is not close to 16.5 and debunks his equation !
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Old 7th April 2021, 08:07 PM   #20
theprestige
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Originally Posted by Mike Helland View Post
Well, this is simple enough:

25 * (Math.sqrt(1+2) - 1)

Have you personally computed the distance to galaxies using dark energy parameters?

Has anyone here?
Well, E=mc^2 is pretty simple, too. But until you actually master the physics behind it, you won't be able to do anything useful, or even intelligible with it. Not at the level you're trying to play at, anyway.
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Old 7th April 2021, 08:57 PM   #21
Mike Helland
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Originally Posted by Reality Check View Post
Repeats his demand that we personally do a calculation when he knows wolframalpha exists ! And that the calculation debunks his made up formula.
8 April 2021: Ignorance of basic mathematics or science: 18.3 is not close to 16.5 and debunks his equation !
How does that debunk anything?

We need to measure the distance to a z=2 galaxy, and that should tell us which model is right.
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Old 8th April 2021, 05:31 AM   #22
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Originally Posted by theprestige View Post
Well, E=mc^2 is pretty simple, too. But until you actually master the physics behind it, you won't be able to do anything useful, or even intelligible with it. Not at the level you're trying to play at, anyway.
E=mc2 is famous because of the atomic bomb, but Einstein's field equations are the fundamental equations of general relativity:

Rμν - ĹRgμν + Λgμν = 8πTμν

Those equations are the starting point for the calculation mentioned here:

Originally Posted by Mike Helland View Post
Have you personally computed the distance to galaxies using dark energy parameters?

Has anyone here?
Yes.

Some years ago, in this subforum, I used the Einstein field equations to derive a special case (for flat spacetime and zero cosmological constant) of the FLRW solutions. The mass/energy density ρ is a parameter of those solutions, and dark energy is part of that density parameter, and the Hubble parameter is one result of that computation.

That calculation was a nice exercise in first-year calculus, so Mike Helland won't understand it. Here's an outline of the calculus involved:

Originally Posted by W.D.Clinger View Post
Finally, we are ready to calculate. Here's what we need to do:
  1. Calculate the 64 partial derivatives of gμν.
  2. Use those partial derivatives and the contravariant gμν to calculate the 64 Christoffel symbols.
  3. Calculate the 256 partial derivatives of those Christoffel symbols.
  4. Use those partial derivatives and Christoffel symbols to calculate the 16 components of the Ricci tensor.
  5. Compute the 16 components of the mixed Ricci tensor by raising one of its indices.
  6. Calculate the Ricci scalar.
  7. Plug the results of those calculations into Einstein's field equations.
  8. Apply some straightforward calculus and algebra to those equations.
It's not quite as tedious as it sounds. Not quite. Not if you pay attention to the hints.

That post contained a couple of minor errors, of which the most embarrassing was

Originally Posted by W.D.Clinger View Post
The highlighted abbreviation should have been "MTW" (Misner, Thorne, and Wheeler). I made that mistake consistently throughout the post.

Here's how the Hubble parameter falls out of that derivation:

Originally Posted by W.D.Clinger View Post
I'll take this opportunity to summarize the key equations.

First Friedmann equation for flat space and zero cosmological constant:
3 ȧ2/a2 = 8πρ
Second Friedmann equation for flat space and zero cosmological constant:
3 ä / a = - 4π (ρ + 3p)
Equation for the rate at which density decreases with expansion:
ρ̇ = - 3 (ȧ / a) (ρ + p)
That last equation holds even without the assumptions of flat space and zero cosmological constant.

By the way, that (ȧ / a) that pops up in two of those three equations is called the Hubble parameter. Its value is closely related to the age and ultimate destiny of the universe.

Last edited by W.D.Clinger; 8th April 2021 at 05:39 AM. Reason: elided a redundant phrase
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Old 8th April 2021, 08:25 AM   #23
Mike Helland
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Originally Posted by W.D.Clinger View Post
Rμν - ĹRgμν + Λgμν = 8πTμν

Yes.

Some years ago, in this subforum, I used the Einstein field equations to derive a special case (for flat spacetime and zero cosmological constant) of the FLRW solutions. The mass/energy density ρ is a parameter of those solutions, and dark energy is part of that density parameter, and the Hubble parameter is one result of that computation.
Well, that's pretty awesome.

Can I ask you then, can the cosmological constant be zero and the dark energy input non-zero?

Is it the case where both a dark energy term and a cosmological constant are needed, or does dark energy make the cosmological constant non-zero?

*edit* An if hypothetically you wanted to calculate the distance of a galaxy z=2 that way, how long would it take? A couple hours? Most of a day?

Last edited by Mike Helland; 8th April 2021 at 08:29 AM.
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Old 8th April 2021, 09:29 AM   #24
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First, a correction: In my previous post, I wrote "flat spacetime" when I meant "flat space".

Originally Posted by Mike Helland View Post
Well, that's pretty awesome.
There was a lot of really good stuff in that old thread, contributed by people like DeiRenDopa, sol invictus, ctamblyn, edd, ben m, Roboramma, lpetrich, and so on. You would do well to read through that thread, taking care to ignore Farsight's posts.

Ziggurat, hecd2, and several others have contributed some good stuff to this thread as well. You should pay more attention to them.

Originally Posted by Mike Helland View Post
Can I ask you then, can the cosmological constant be zero and the dark energy input non-zero?
Yes. My derivation covers that situation under the additional assumption of flat space, and I gave you a link to a Wikipedia article that covers the generalization to non-flat space.

Originally Posted by Mike Helland View Post
Is it the case where both a dark energy term and a cosmological constant are needed, or does dark energy make the cosmological constant non-zero?
That's to be settled by observation. The FLRW solutions allow dark energy in the mass/energy parameter, or in the cosmological constant, or in both together (which is the most general of those situations).

Originally Posted by Mike Helland View Post
*edit* An if hypothetically you wanted to calculate the distance of a galaxy z=2 that way, how long would it take? A couple hours? Most of a day?
I'm not at all sure you understand that z=2 specifies a specific redshift, and that such a redshift does not by itself determine the distance to a light source with that redshift. To calculate a distance, you would need some additional assumptions, such as a value for Hubble's parameter.

Someone who accepts Hubble's Law and mainstream estimates for the Hubble parameter would be able to calculate the distance corresponding to z=2 in a matter of seconds, using nothing more than a slide rule. The Friedmann equations aren't needed for that calculation, and become relevant only when you want to understand the relationship between Hubble's parameter and other parameters that include dark energy; that relationship is part of the science that contributes to mainstream estimates of dark energy.

Considerable research has gone into estimating Hubble's parameter, but you have been rejecting much of the science on which that research is based. In particular, you have been advocating ideas that are completely incompatible with relativity (and several other major areas of physics). I therefore have absolutely no idea of how you would go about forming any kind of scientific basis for calculating the distance to a light source with redshift z=2. Judging by what you have written in this thread and its predecessor, you don't either.
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Old 8th April 2021, 09:58 AM   #25
Mike Helland
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Originally Posted by W.D.Clinger View Post
There was a lot of really good stuff in that old thread, contributed by people like DeiRenDopa, sol invictus, ctamblyn, edd, ben m, Roboramma, lpetrich, and so on. You would do well to read through that thread, taking care to ignore Farsight's posts.

Ziggurat, hecd2, and several others have contributed some good stuff to this thread as well. You should pay more attention to them.
Thanks.

My calculations and hypotheses have changed quite a bit, thanks to their input.

It might seem like I learn nothing, as I plow ahead. But I don't think that's true.

Quote:
That's to be settled by observation. The FLRW solutions allow dark energy in the mass/energy parameter, or in the cosmological constant, or in both together (which is the most general of those situations).
Very interesting. Thank you.

Quote:
Considerable research has gone into estimating Hubble's parameter, but you have been rejecting much of the science on which that research is based.
Ok, to be fair, rather than say "rejecting", I'm open to the possibility the history of the universe can be derived from the CMB, and I'm open to the idea the CMB does not tell us the history of the universe.

Quote:
In particular, you have been advocating ideas that are completely incompatible with relativity (and several other major areas of physics). I therefore have absolutely no idea of how you would go about forming any kind of scientific basis for calculating the distance to a light source with redshift z=2. Judging by what you have written in this thread and its predecessor, you don't either.
Ok. Check this out.

What I did is made a model of a photon and targets in space in space and they all move away at Hubble's law, and calculate the z based on the expansion of space stretching the wavelength.

https://mikehelland.github.io/hubbles-law/test.htm

Then I made another model where the targets are stationary, but the photon moves at v=c-HD. This makes the same z's.

I can just put the z I'm looking for the z input box on that page, and it'll report the distance at that z.

Here, I notice that v=c/(1+z), so c/(1+z)=c-HD.

I solve that for D = (c - c/(1+z))/H

So instead of running my program for all possible values of z until I get to where I want, I can just use that equation to punch in z.

That should legit for a basic expanding universe. That must be well known.

Annnnyyways, we notice that the universe is not simply expanding. It's accelerating in its expansion.

So, I look at v=c-HD, and say "how do I make this redshift less as z gets larger (*edit* D gets larger)", and it turns out v=c/(1+HD)2 works.



H is not H0, by the way. In that specific formulation, H is inverse distance. So I changed it to v=c/(1+D/H)2 using plain old distance for units of H.

Then I made a model

In this case, the same pattern where v=c/(1+z) persists.

So now, 1+z=(1+D/H)2

I can plug in any z where we have observational data, and get the right answer as the standard model.

Where we don't have z-distance data, this hypothesis predicts something very different than the standard model.



Since the slow photon is counter to physics, the hypothesis is instead framed as time dilation of cosmologically redshifted photons.





For an original frequency ν and original wavelength λ, the new frequency ν' is:



So, if my calculations are right, this redshift distance relation ought to put out the same distances for z<1 as the standard model, when you include dark energy.

Last edited by Mike Helland; 8th April 2021 at 10:12 AM. Reason: changed 1's to c's
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Old 8th April 2021, 11:15 AM   #26
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Before going on, I should retract this paragraph:

Originally Posted by W.D.Clinger View Post
Someone who accepts Hubble's Law and mainstream estimates for the Hubble parameter would be able to calculate the distance corresponding to z=2 in a matter of seconds, using nothing more than a slide rule. The Friedmann equations aren't needed for that calculation, and become relevant only when you want to understand the relationship between Hubble's parameter and other parameters that include dark energy; that relationship is part of the science that contributes to mainstream estimates of dark energy.
A redshift of z=2 is large enough to invalidate low-redshift approximations that make it easy to calculate proper distance using nothing more than a slide rule. Furthermore, the Friedmann equations are certainly relevant when the calculation involves large redshifts. For a derivation of Hubble's law from the FLRW models, see
Edward Harrison. The redshift-distance and velocity-distance laws. The Astrophysical Journal, 403:28-31, 1993 January 20.
From the abstract:
Originally Posted by Harrison
The distinction between Hubble's linear redshift-distance z(L) law and the linear velocity-distance V(L) law that emerged later is discussed, using first the expanding space paradigm and then the Robertson-Walker metric. The z(L) and V(L) laws are theoretically equivalent only in the limit of small redshifts....

Turning now to Mike Helland's post above, with my highlighting:

Originally Posted by Mike Helland View Post
Here, I notice that v=c/(1+z), so c/(1+z)=c-HD.

At small redshifts, v≈cz. Somehow, Mike Helland was able to "notice" that "v=c/(1+z)". If I were mathematically inclined, I might notice that Mike Helland's equation is very much at odds with the small-redshift approximation, and would therefore have reason to doubt whether Mike Helland's equation is remotely accurate.

Consider, for example, the tiniest shift possible: z=0. The v≈cz approximation says z=0 corresponds to a recessional velocity of zero. Mike Helland's equation says z=0 corresponds to a recessional velocity of v=c.

ETA: Now that I've spent some time laughing about this, I think Mike Helland is using v to stand not for recessional velocity, which is the meaning of v in Hubble's law, but for the speed of a photon that is just plumb tuckered out after travelling a distance D.

Last edited by W.D.Clinger; 8th April 2021 at 11:36 AM. Reason: see ETA
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Old 8th April 2021, 11:35 AM   #27
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Originally Posted by W.D.Clinger View Post
For a derivation of Hubble's law from the FLRW models, see
Edward Harrison. The redshift-distance and velocity-distance laws. The Astrophysical Journal, 403:28-31, 1993 January 20.
Thanks.

Quote:
Consider, for example, the tiniest shift possible: z=0. The v≈cz approximation says z=0 corresponds to a recessional velocity of zero. Mike Helland's equation says z=0 corresponds to a recessional velocity of v=c.
v in these hypotheses is the speed of the photon. v=c when D=0 and decreases as D increases:

vlight=c-HD (simple)

or

vlight = c/(1+D/H)2 (accelerating).

And, like I said, since a slow photon is no good, the revised hypothesis has no v, it's about a dynamic experience of time, rather than changing velocity.
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Old 8th April 2021, 11:52 AM   #28
Mike Helland
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Originally Posted by W.D.Clinger View Post
ETA: Now that I've spent some time laughing about this, I think Mike Helland is using v to stand not for recessional velocity, which is the meaning of v in Hubble's law, but for the speed of a photon that is just plumb tuckered out after travelling a distance D.
The idea is that EM radiation starts to fall off in a different way at huge distances and we observe that as redshift.

In an attempt to make this fit better with the laws of physics, the photon doesn't actually change velocity (according to its experience of time), but its experience of time changes based on how many millions of light years its traveled.

Here's what I'm saying, the redshifts and time delays of a basic expanding universe can be made three different ways:

A: Expanding space (v=H0D)
B: Expanding time (Δt'= Δt-HD)
C: Decelerating photon (vlight=c-HD)

Based on what we know now about redshifts and distance, a linear expansion rate is not good enough. B and C can be easily adapted to the new data using an inverse square law.

But, even if the interpretation of redshifts I'm using is all wrong, the redshift-distance relation I have seems to work for the data we have, and it makes predictions that differ from the standard model where we don't have data.
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Old 8th April 2021, 12:46 PM   #29
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Originally Posted by Mike Helland View Post
Thanks.



v in these hypotheses is the speed of the photon. v=c when D=0 and decreases as D increases:

vlight=c-HD (simple)

or

vlight = c/(1+D/H)2 (accelerating).

And, like I said, since a slow photon is no good, the revised hypothesis has no v, it's about a dynamic experience of time, rather than changing velocity.
As usual, you are too ignorant to realize that your own equations cannot possibly be correct.
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Old 8th April 2021, 01:00 PM   #30
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Originally Posted by Crossbow View Post
As usual, you are too ignorant to realize that your own equations cannot possibly be correct.
The units of the constant in these non-standard z-distance relations are not the standard km/s/Mpc.

*edit* And the units in the linear and non-linear variations are not the same either.

Last edited by Mike Helland; 8th April 2021 at 01:01 PM.
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Old 8th April 2021, 02:49 PM   #31
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Originally Posted by Mike Helland View Post
Thanks.



v in these hypotheses is the speed of the photon. v=c when D=0 and decreases as D increases:

vlight=c-HD (simple)

or

vlight = c/(1+D/H)2 (accelerating).

And, like I said, since a slow photon is no good, the revised hypothesis has no v, it's about a dynamic experience of time, rather than changing velocity.
Once again you show that you do not understand how units work.
In order for the first equation to work the H*D equation MUST give m/s, as otherwise you cannot subtract.
In which case your second equation becomes nonsense.

On the other hand if you make D/H unitless as is needed in your second equation then your first equation becomes nonsense.

Since you are incapable of basic mathematics, why would anything you claim to calculate be something that the rest of the world should listen to?
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Old 8th April 2021, 02:49 PM   #32
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Originally Posted by Crossbow View Post
As usual, you are too ignorant to realize that your own equations cannot possibly be correct.
Actually this is Mike Helland's idiocy of using an "H" symbol that is not Hubble's constant, or anything to do with Hubble or cosmology or physics !
A high school math student would use a, b, c, d, etc. when fitting an arbitrary equation to data. A high school science student might avoid "c" so that it is not confused with the speed of light.
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Old 8th April 2021, 02:56 PM   #33
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Exclamation An idiotic "How does that debunk anything" question rom Mike Helland

Originally Posted by Mike Helland View Post
How does that debunk anything?
9 April 2021: An idiotic "How does that debunk anything" question rom Mike Helland.
8 April 2021: Ignorance of basic mathematics or science: 18.3 is not close to 16.5 and debunks his equation !
The real world physics found from the supernova data gets 16.5 billion light years. This is not his 18.3 billion light years found by fitting the same data !

Followed by "We need to measure the distance to a z=2 galaxy, and that should tell us which model is right." stupidity. Galaxies do not just exist at z = 2! We can do the same for galaxies in his data and get the same result - his curve fitting does not match the real universe.

Last edited by Reality Check; 8th April 2021 at 02:59 PM.
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Old 8th April 2021, 03:18 PM   #34
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Exclamation An incorrect statement when he has a history of not learning

Originally Posted by Mike Helland View Post
It might seem like I learn nothing, as I plow ahead. But I don't think that's true. ....
9 April 2021: An incorrect statement when he has a history of not learning and still has not learned textbook physics or even what physics is !

There is open-minded and there is a mind so open that its brain falls out .
Mike Helland has still not learned that curve fitting is mathematics, not physics. Physics is when the equation for the curve is derived from physical laws and fits the data.
Mike Helland has still not learned that the CMB must come from a universe in a hot dense state. The CMB can only exist in an expanding universe.
Mike Helland has still not learned that v=c-HD does not produce any z at all. The wavelength of photos only depends on their energy. Ditto for any v(x) equation he makes up.
Mike Helland has still not learned about basic relativity Thus "time dilation of cosmologically redshifted photons" is nonsense. Time dilation does not magically appear . Time dilation is relative to an observer's speed and gravitational field. Photons have a "clock" with an undefined time.
Mike Helland has still not learned about scientific scholarship. When you have a plot of data it is standard to cite the sources of the data source along with the graph.
Mike Helland has still not learned about Google or Wikipedia . List of most distant supernovae has SN UDS10Wil at z= 1.914. It is possible that this 2013 observation has had its distance determined from its light curve.

Last edited by Reality Check; 8th April 2021 at 03:32 PM.
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Old 8th April 2021, 04:28 PM   #35
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Originally Posted by Mike Helland View Post
The units of the constant in these non-standard z-distance relations are not the standard km/s/Mpc.

*edit* And the units in the linear and non-linear variations are not the same either.
And nonsense posting like this only serves to show just how completely ignorant you are about this subject.
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Last edited by Crossbow; 8th April 2021 at 05:18 PM. Reason: Typo correction
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Old 8th April 2021, 05:09 PM   #36
W.D.Clinger
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Originally Posted by Crossbow View Post
As usual, you are too ignorant to realize that your own equations cannot possibly be correct.
Originally Posted by Mike Helland View Post
The units of the constant in these non-standard z-distance relations are not the standard km/s/Mpc.

*edit* And the units in the linear and non-linear variations are not the same either.
Originally Posted by Lukraak_Sisser View Post
Once again you show that you do not understand how units work.
In order for the first equation to work the H*D equation MUST give m/s, as otherwise you cannot subtract.
In which case your second equation becomes nonsense.

On the other hand if you make D/H unitless as is needed in your second equation then your first equation becomes nonsense.

Since you are incapable of basic mathematics, why would anything you claim to calculate be something that the rest of the world should listen to?
Originally Posted by Reality Check View Post
Actually this is Mike Helland's idiocy of using an "H" symbol that is not Hubble's constant, or anything to do with Hubble or cosmology or physics !

Hubble's law is expressed by the equation v=HD. That equation mentions three letters. Mike Helland has assigned nonstandard meanings to two of those letters (v and H), has given two entirely different nonstandard meanings to the letter H within the space of a single post, and probably doesn't comprehend the standard meaning of the letter D. (Comprehension would require some understanding of the distinction between proper and co-moving distance.)

For some purposes, miscommunication is a feature, not a bug.
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Old 8th April 2021, 05:14 PM   #37
Mike Helland
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Originally Posted by Lukraak_Sisser View Post
Once again you show that you do not understand how units work.
In order for the first equation to work the H*D equation MUST give m/s, as otherwise you cannot subtract.
In which case your second equation becomes nonsense.

On the other hand if you make D/H unitless as is needed in your second equation then your first equation becomes nonsense.

Since you are incapable of basic mathematics, why would anything you claim to calculate be something that the rest of the world should listen to?
Those are alternative, competing hypotheses.

They aren't both meant to be true.
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Old 8th April 2021, 05:19 PM   #38
Mike Helland
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Originally Posted by Reality Check View Post
Actually this is Mike Helland's idiocy of using an "H" symbol that is not Hubble's constant, or anything to do with Hubble or cosmology or physics !
A high school math student would use a, b, c, d, etc. when fitting an arbitrary equation to data. A high school science student might avoid "c" so that it is not confused with the speed of light.
Sure.

v=H0D
vlight=c-aD
Δt'= Δt-bD
Δt'= Δt/(1+D/d)

There. I used a, b, and d instead of H.

Happy?
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Old 8th April 2021, 06:36 PM   #39
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Originally Posted by Mike Helland View Post
Happy?
Not happy that it took you so long to understand a simple concept. Happy that you now understand that you are just doing curve fitting with no physics. This is not cosmology or physics.
Unhappy that you are repeating the delta t (""time dilation of cosmologically redshifted photons" is nonsense") idiocy. More idiocy is your delta t equation magically appearing in a graph of distance versus z with supernova data.

The fundamental things you need to understand are.
  • Your guessed at functions say nothing physical about the Big Bang or indeed any universe.
    There is still an enormous body of physical evidence that the universe is expanding.
  • The meaning of the word hypotheses when you write "Those are alternative, competing hypotheses." !
    A scientific hypothesis is an "educated guess" with the potential to lead to a scientific theory. They start with knowing the physics involved which you obviously do not.
    Ignorant guesses are not hypotheses. Guessing at functions to fit data are not hypotheses.

Last edited by Reality Check; 8th April 2021 at 06:49 PM.
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Old 8th April 2021, 06:41 PM   #40
Mike Helland
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Originally Posted by Reality Check View Post
There is still an enormous body of physical evidence that the universe is expanding.
20 years ago I would have been right there with you.

The redshifts, the CMB, and the apparent evolution of galaxies throughout time.

Since then we've gotten the Hubble tension, the CMB anomalies, and unexpectedly massive, dusty, ordered galaxies have been found at incredible distances.

A little skepticism wouldn't hurt.
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