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Old 16th November 2022, 08:09 AM   #241
Mike Helland
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Originally Posted by steenkh View Post
There is nothing new in the question of the Hubble constant. Is the paper offering tired light as a solution?
This one?

https://arxiv.org/abs/2211.04492

Far from it.

But as far as nothing new, I can predict lookback times using a Hubble's constant that is actually constant.
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Old 16th November 2022, 08:35 AM   #242
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Originally Posted by W.D.Clinger View Post
I was unsure about the highlighted part, and it bothered me that Cappi placed equation (7) after equation (6) when he was so careful to place all of the other equations that you needed before performing the calculation implied by (6) before equation (6). I have now figured out how to calculate the lookback distance according to equation (6) without needing equation (7), and will explain in a few days when I have time to write it up.
That's an interesting observation.

Comparing the paper to his JavaScript implementation you can see that lookback time somewhat stands alone:

Code:
        // Lookback time
        lookback = timeint(1., z1) * Tnorm
        // Angular distance
        DA = DL / (z1 * z1)
        // Lunghezza in primi corrispondente a 1 Mpc.
        angle = (60. / rad) * z1 * z1 / DL;
        // Length in Mpc corresponding to 1 degree on the sky
        R = rad * DL / (z1 * z1);
I look forward to your write up.
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Old 16th November 2022, 10:33 AM   #243
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Originally Posted by Mike Helland View Post
Of course it does. That's why we're talking about it.
Nope, you are talking about a way of describing redshift to explain the evidence it provides for accelerated expansion. The ISW and BAO observations have nothing to do with redshift. So, forget the redshift, you need to deal with them as a minimum before even bothering with redshift.
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Old 16th November 2022, 11:00 AM   #244
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Originally Posted by jonesdave116 View Post
Nope, you are talking about a way of describing redshift to explain the evidence it provides for accelerated expansion.
The discrepancy between expecting a matter dominated model (omegaM=1) and what was observed was significant.

Do you disagree?
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Old 16th November 2022, 09:05 PM   #245
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Originally Posted by Mike Helland View Post
The discrepancy between expecting a matter dominated model (omegaM=1) and what was observed was significant.

Do you disagree?
One would hope to see a discrepancy, since ΩM=1 is not at all consistent with mainstream cosmology's estimates of that parameter.

Are you telling us that Helland physics expects ΩM=1?

Or does Helland physics expect ΩM=0, as you told us you assumed when deriving your Helland equation for a relationship between red shift and distance?
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Old 16th November 2022, 09:38 PM   #246
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Originally Posted by W.D.Clinger View Post
One would hope to see a discrepancy, since ΩM=1 is not at all consistent with mainstream cosmology's estimates of that parameter.

Are you telling us that Helland physics expects ΩM=1?

Or does Helland physics expect ΩM=0, as you told us you assumed when deriving your Helland equation for a relationship between red shift and distance?
Mainstream is that its about 30% matter and 70% dark energy.

Do you disagree?
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Old 17th November 2022, 10:50 AM   #247
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Originally Posted by W.D.Clinger View Post
Mike Helland's equation for calculating distance from red shift does not involve any of the FLRW parameters, which was an extremely strong clue that the Helland equation is not based upon mainstream physics. In a recent post, however, Mike Helland has said his equation assumes a universe devoid of matter, which establishes the value Mike Helland's equation assumes for one of the FLRW parameters....

Helland's equation is
d = (z/(1+z)) c/H0
Originally Posted by W.D.Clinger View Post
(For some reason, Mike Helland stubbornly persists in writing a more complicated equivalent of that equation, perhaps because the more complicated way of writing the equation makes it harder to compare against mainstream equations such as Cappi's.)
Originally Posted by W.D.Clinger View Post
If you are assuming matter doesn't affect redshifts, then you are assuming Helland physics rather than mainstream physics. That is part of why your Helland equation for the relationship between red shift and distance is far less complicated than the mainstream equations for that relationship. (The other reason your equation is less complicated is that it either doesn't take model parameters into account, or it assumes those parameters have whatever fixed values you think they have in Helland physics.)
Originally Posted by Mike Helland View Post
My equation is derived from inverting redshift formulas. That's all.

It could be that it matches a universe where matter doesn't affect redshift is just a bizarre coincidence.
Originally Posted by Mike Helland View Post
I can predict lookback times using a Hubble's constant that is actually constant.
Originally Posted by Mike Helland View Post
The discrepancy between expecting a matter dominated model (omegaM=1) and what was observed was significant.

Do you disagree?
Originally Posted by W.D.Clinger View Post
One would hope to see a discrepancy, since ΩM=1 is not at all consistent with mainstream cosmology's estimates of that parameter.

Are you telling us that Helland physics expects ΩM=1?

Or does Helland physics expect ΩM=0, as you told us you assumed when deriving your Helland equation for a relationship between red shift and distance?
Originally Posted by Mike Helland View Post
Mainstream is that its about 30% matter and 70% dark energy.

Do you disagree?

Why don't you quit dancing around and just tell us the values of the parameters that are wired into your Helland equation?

You have insisted throughout that your Helland equation is based upon mainstream physics. But the mainstream equations that relate distance to red shift are considerably more complicated than your Helland equation, partly because that relationship is model-dependent. Unlike mainstream equations, your Helland equation mentions no model parameters apart from H0. That means your Helland equation implicitly assumes certain values for the other model parameters on which mainstream equations depend.

What parameter values did you assume when you formulated your Helland equation?
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Old 17th November 2022, 11:26 AM   #248
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Originally Posted by W.D.Clinger View Post
Why don't you quit dancing around and just tell us the values of the parameters that are wired into your Helland equation?

You have insisted throughout that your Helland equation is based upon mainstream physics. But the mainstream equations that relate distance to red shift are considerably more complicated than your Helland equation, partly because that relationship is model-dependent. Unlike mainstream equations, your Helland equation mentions no model parameters apart from H0. That means your Helland equation implicitly assumes certain values for the other model parameters on which mainstream equations depend.

What parameter values did you assume when you formulated your Helland equation?
The equation is derived by simply inverting the redshift equations. Apparently no one else thought of that.

You know what the values of the cosmological parameters are.
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Old 17th November 2022, 06:07 PM   #249
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Originally Posted by Mike Helland View Post
The equation is derived by simply inverting the redshift equations. Apparently no one else thought of that.
So you believe
z = d / ((c/H0) - d)
is a mainstream physics equation? Citation needed!

According to your Helland equation
d = (z / (1+z)) c/H0
a red shift of z=1 corresponds to a distance of about 7 billion light years.

According to mainstream physics, a red shift of z=1 corresponds to a proper distance of about 10 billion light years, or 7.7 billion light years if you naively multiply the lookback time by the speed of light.

Even with the most charitable interpretation of your Helland equation, it's about 10% off from the best estimates of mainstream physics.
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Old 18th November 2022, 11:17 AM   #250
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Originally Posted by Mike Helland View Post
The discrepancy between expecting a matter dominated model (omegaM=1) and what was observed was significant.

Do you disagree?
Sorry? The EVIDENCE says the universe is accelerating in its expansion. And those observations do not all include redshift. As mentioned, the ISW and BAO observations strongly support an accelerated expansion. The former, at least, was predicted.
So, faffing around with redshift equations is not going to make those predicted observations disappear, is it? Just as the CMB is not going to disappear, regardless of crank claims about what JWST has shown.
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Old 18th November 2022, 12:26 PM   #251
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Originally Posted by W.D.Clinger View Post
So you believe
z = d / ((c/H0) - d)
is a mainstream physics equation? Citation needed!
No. This is a mainstream physics equation 1+z=Eemit/Eobs.

I just inverted it, so the range of redshifts is a percentage, which is what that integral is doing anyways.

Quote:
According to your Helland equation
d = (z / (1+z)) c/H0
a red shift of z=1 corresponds to a distance of about 7 billion light years.

According to mainstream physics, a red shift of z=1 corresponds to a proper distance of about 10 billion light years, or 7.7 billion light years if you naively multiply the lookback time by the speed of light.

Even with the most charitable interpretation of your Helland equation, it's about 10% off from the best estimates of mainstream physics.
And according to LCDM, H0 should be 68, but we measure it to be 74. Mainstream physics is famously in tension with observation.
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Old 18th November 2022, 02:13 PM   #252
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Originally Posted by Mike Helland View Post
No. This is a mainstream physics equation 1+z=Eemit/Eobs.
Nope, that is an approximation, and only valid at small z. In other words <<1.


Quote:
And according to LCDM, H0 should be 68, but we measure it to be 74. Mainstream physics is famously in tension with observation.
No, we have varying measurements of it, depending on whether the measurement are 'close' or distant. Which could imply new physics. Yippee!

What it does not imply is that the universe is not expanding. Use whatever value you can find, and it leads to the same conclusion.

People who want static universes need not only to overturn the redshift evidence, they need to overturn, and explain at least as well, the other observations, which show that we are in a universe which is accelerating in its expansion. Nobody can. Which is why nobody is even bothering anymore.
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Old 18th November 2022, 04:43 PM   #253
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Originally Posted by jonesdave116 View Post
Nope, that is an approximation, and only valid at small z. In other words <<1.
Nope, that is how redshift z is quantified.

Your thinking of the redshift-distance relationship.

If you try to use with d = cz / H0, you will find this equation to be an approximation.

However, by inverting the redshift function, you are multiplying c/H0 by a percentage (rather than to infinity).

Which is what the lookback integral is doing too.
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Old 18th November 2022, 06:58 PM   #254
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Originally Posted by W.D.Clinger View Post
One would hope to see a discrepancy, since ΩM=1 is not at all consistent with mainstream cosmology's estimates of that parameter.

Are you telling us that Helland physics expects ΩM=1?

Or does Helland physics expect ΩM=0, as you told us you assumed when deriving your Helland equation for a relationship between red shift and distance?
Prior to 1998, it was thought that ΩM=1.

Since that was younger than the oldest stars, that couldn't be right. Using supernovae data they figured there needs to be the right amount of dark energy to negate the effects of matter. That ends up being ΩM=~0.3 and ΩΛ=~0.7.

Redshifts in Helland physics (your name) aren't affected by gravity, so dark energy isn't necessary to counteract its affects.
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Old 18th November 2022, 08:08 PM   #255
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Originally Posted by W.D.Clinger View Post
Helland's equation is
d = (z/(1+z)) c/H0
Originally Posted by Mike Helland View Post
The equation is derived by simply inverting the redshift equations. Apparently no one else thought of that.
Originally Posted by W.D.Clinger View Post
So you believe
z = d / ((c/H0) - d)
is a mainstream physics equation? Citation needed!
Originally Posted by Mike Helland View Post
No. This is a mainstream physics equation 1+z=Eemit/Eobs.

I just inverted it, so the range of redshifts is a percentage, which is what that integral is doing anyways.
No. That "1+z=Eemit/Eobs" does not mention d at all, so it cannot be inverted to obtain an equation for d.

The only equation that could possibly be inverted to obtain your Helland equation
d = (z/(1+z)) c/H0
is
z = d / ((c/H0) - d)
or some algebraic equivalent of that equation. Unsurprisingly, you have been unable to find a citation for any such equation in the mainstream literature.

That refutes your claim that your Helland equation was derived by inverting a mainstream equation.

Originally Posted by Mike Helland View Post
Prior to 1998, it was thought that ΩM=1.

Since that was younger than the oldest stars, that couldn't be right.
It takes a special level of cluelessness to think ΩM=1, taken in isolation, tells you anything about the age of stars. To infer anything about the age of stars, you have to combine that parameter with other observations and with the details of a mathematical model.

I'm away from my library at the moment, but when I get back I will give you citations showing that mainstream cosmology of the 1970s was already estimating ΩM to be considerably less than 1.

ETA: This spoiler contains the promised citations and quotations, obtained from an online search instead of my library.
In 1976, P J E Peebles used A Cosmic Virial Theorem to estimate
0.05 < ΩM < 0.5
without proclaiming a great deal of confidence in that estimate. In 1983, that estimate was refined to ΩM ~ 0.2 plus or minus 0.1, which became the standard estimate until the modern mainstream estimate of ΩM ~ 0.3 became even more definitively established some 25 years ago (in 1998, as Mike Helland observed). As explained by James G. Bartlett and Alain Blanchard in 1995:
Quote:
Since its inception (Peebles 1976a,b), the so-called 'cosmic virial theorem' (CVT) has been considered one of the most reliable indicators of the cosmic mean matter density, and for good reason....

The theorem...was conscripted immediately (Peebles 1976a,b), but not with convincing results until the completion of the first CfA redshift survey (Davis & Peebles 1983)...Davis and Peebles concluded that Ω ~ 0.2....Such a low value of the mean density affronts the theorist's preference for a flat Universe....


Originally Posted by Mike Helland View Post
Redshifts in Helland physics (your name) aren't affected by gravity, so dark energy isn't necessary to counteract its affects.
In mainstream physics, redshifts are affected by gravity, and the mainstream equations for estimating distance from redshift therefore have to take gravity into account.

That is yet another proof that your mainstream equation for distance as a function of red shift is incompatible with mainstream physics.

Last edited by W.D.Clinger; 18th November 2022 at 09:27 PM. Reason: added ETA and its spoiler
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Old 19th November 2022, 01:59 AM   #256
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Originally Posted by W.D.Clinger View Post
No. That "1+z=Eemit/Eobs" does not mention d at all
I never said it did.

Quote:
The only equation that could possibly be inverted to obtain your Helland equation
d = (z/(1+z)) c/H0
is
z = d / ((c/H0) - d)
or some algebraic equivalent of that equation. Unsurprisingly, you have been unable to find a citation for any such equation in the mainstream literature.

That refutes your claim that your Helland equation was derived by inverting a mainstream equation.
You're confusing equations for redshift and equations for a redshift-distance relationship.

My equation for blueshift is just the equation for redshift inverted.

My equation for blueshift-distance relatoinship is a conjecture.

If d = zc/H0 was what was initially thought to be redshift-distance relationship, but we discovered it was inaccurate over most of its domain, then I conjectured d = -bc/H0.

It's not easy to compare two equations that have different variables, but since 1+b=1/(1+z), then b=1/(1+z)-1.


Quote:
It takes a special level of cluelessness to think ΩM=1, taken in isolation, tells you anything about the age of stars.
Here's what Nobel prize winner Riess says about his discovery:

"Coupled with the theoretical expectation of Ω m ∼ 1, the low expansion age implied by these measurements, still a few Gyr younger than the oldest stars, set off another “Hubble tension” until the discovery of cosmic acceleration amended the composition and recent expansion history and the age of the Universe grew comfortably higher."

Last edited by Mike Helland; 19th November 2022 at 03:08 AM.
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Old 19th November 2022, 04:11 AM   #257
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Originally Posted by Mike Helland View Post
Originally Posted by W.D.Clinger View Post
No. That "1+z=Eemit/Eobs" does not mention d at all
I never said it did.
What you did say is that you obtained your Helland equation involving d by inverting that equation, which does not even mention d.

From those facts, it has long been clear that your oft-repeated claim about your Helland equation being consistent with mainstream physics is false.

From your ongoing attempts to deflect attention away from those facts and that conclusion (of which your "I never said it did" is just the most recent example), it is fair to conclude that your oft-repeated claim about your Helland equation being consistent with mainstream physics is not just false, but an outright lie.

Here is the context, which I quoted just a few posts above:
Originally Posted by W.D.Clinger View Post
Originally Posted by W.D.Clinger View Post
Helland's equation is
d = (z/(1+z)) c/H0
Originally Posted by Mike Helland View Post
The equation is derived by simply inverting the redshift equations. Apparently no one else thought of that.
Originally Posted by W.D.Clinger View Post
So you believe
z = d / ((c/H0) - d)
is a mainstream physics equation? Citation needed!
Originally Posted by Mike Helland View Post
No. This is a mainstream physics equation 1+z=Eemit/Eobs.

I just inverted it, so the range of redshifts is a percentage, which is what that integral is doing anyways.
No. That "1+z=Eemit/Eobs" does not mention d at all, so it cannot be inverted to obtain an equation for d.

The only equation that could possibly be inverted to obtain your Helland equation
d = (z/(1+z)) c/H0
is
z = d / ((c/H0) - d)
or some algebraic equivalent of that equation. Unsurprisingly, you have been unable to find a citation for any such equation in the mainstream literature.

That refutes your claim that your Helland equation was derived by inverting a mainstream equation.

Now you say:
Originally Posted by Mike Helland View Post
Quote:
The only equation that could possibly be inverted to obtain your Helland equation
d = (z/(1+z)) c/H0
is
z = d / ((c/H0) - d)
or some algebraic equivalent of that equation. Unsurprisingly, you have been unable to find a citation for any such equation in the mainstream literature.

That refutes your claim that your Helland equation was derived by inverting a mainstream equation.
My equation for blueshift is just the equation for redshift inverted.

If d = zc/H0 was what was initially thought to be redshift relationship, but we discovered it was inaccurate over most of its domain, then I conjectured d = -bc/H0.

It's not easy to compare two equations that have different variables, but since 1+b=1/(1+z), then b=1/(1+z)-1.
In other words, you took an equation that, in mainstream physics, had long been known to be an approximation useful only at small redshifts, messed with it enough to confuse yourself ("It's not easy to compare two equations that have different variables"), obtained your Helland equation by (in effect) multiplying by z (a modification you have yet to explain or justify), and used that Helland equation to calculate distances corresponding to large redshifts that are far outside the domain of applicability of the mainstream equation you are now citing as (apparently) the sole basis for your Helland equation.

Which was silly, but here's what was really dishonest: When you believed your silly Helland equation led to inconsistencies, you alleged that was a problem for mainstream physics, rather than a problem for Helland physics.

When pressed on that, you say silly things about mainstream physics. This is a recent example:
Originally Posted by Mike Helland View Post
Prior to 1998, it was thought that ΩM=1.

Since that was younger than the oldest stars, that couldn't be right.
As I wrote earlier, it takes a special level of cluelessness to think ΩM=1, taken in isolation, tells you anything about the age of stars. To infer anything about the age of stars, you have to combine that parameter with other observations and with the details of a mathematical model.

Besides, you have the history all wrong. The density parameters are fractions of the critical density. Mainstream theorists wanted the sum of those fractions to add up to 1 (the critical density), because observational evidence was consistent with a flat or nearly flat universe, and a flat universe simplifies the theory. Mainstream theorists also wanted ΩΛ=0, because a zero cosmological constant also simplifies the theory; besides, Einstein regretted his addition of that constant to his field equations (even though, mathematically speaking, that constant belonged in his field equations just as much as the constant that belongs in a calculus student's solution for an indefinite integral), and Einstein's opinions were pretty influential.

A problem arose when, beginning in 1976 and further confirmed in 1983, calculations based on actual observations strongly suggested ΩM ~ 0.3. The theorists didn't like that, as was mentioned in my quotation of a 1995 paper. By 1998 or thereabouts, the discrepancy between ΩM ~ 0.3 and the theorists' desires was resolved when the theorists gave up on their idea that ΩΛ=0.

That is what Reiss was talking about:
Originally Posted by Mike Helland View Post
Ignoring how rude you've been, here's what Nobel prize winner Riess says about his discovery:

"Coupled with the theoretical expectation of Ω m ∼ 1, the low expansion age implied by these measurements, still a few Gyr younger than the oldest stars, set off another “Hubble tension” until the discovery of cosmic acceleration amended the composition and recent expansion history and the age of the Universe grew comfortably higher."
I have highlighted some phrases you misunderstood.

ΩM ~ 1 was a "theoretical expectation" on the part of theorists who wanted the simpler theory you get with flat spacetime and a zero cosmological constant.

Unfortunately for the theorists, the best estimate based on mainstream physics was ΩM ~ 0.3. That estimate has been pretty stable since the mid-1980s, when it improved upon the 1976 conclusion that ΩM < 0.5.

If you combine ΩM ~ 0.3 (based on measurements) with ΩΛ=0 (which was based upon little more than the theorists' hopes and Einstein's influence) and plug those values (along with some others) into the FLRW models for an expanding universe, you get an age for the universe that is younger than the apparent age of some extremely distant objects. That is the "Hubble tension" of which Reiss spoke in your quotation.

Reiss's "amended...composition" of the universe was achieved by retaining the ΩM ~ 0.3 estimate of the 1980s while accepting the reality of dark energy in the form of a non-zero cosmological constant, with ΩΛ > 0.
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Old 19th November 2022, 04:34 AM   #258
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Originally Posted by W.D.Clinger View Post
What you did say is that you obtained your Helland equation involving d by inverting that equation, which does not even mention d.
False.

You keep saying "Helland equation" but you keep confusing two different things.

1 + z = Eemit / Eobs

That's a mainstream equation for redshift.

Invert it. What do you have?

1/(1 + z) = Eobs / Eemit

You can call that the Helland blueshift equation if you'd like.

1+b =1/(1+z)

That's how the two values are related.

Now I find this interesting, because while the range of z for valid redshifts is 0<z<infinity, the range of b for valid redshifts is -1<b<0.

z goes to infinity, while b only goes to -1.

Let's look at the lookback time integral.



t(z)=1/H0 * an integral

As z goes to infinity, t approaches 1/H0. It will never get larger than that.

So the integral must go from 0 to a limit of 1 (rather than infinity).

I could just do this t(z)=1/H0 * -b.

You can call that the blueshift-lookback time relationship if you want.

I can also propose d = -bc / H0, since d=ct.

You can call that the Helland blueshift-distance relationship if you want. But you're just being confusing by giving different things the same name.
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Old 19th November 2022, 05:13 AM   #259
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Originally Posted by Mike Helland View Post
Let's look at the lookback time integral.

That's Cappi's equation (7).

Originally Posted by Mike Helland View Post
t(z)=1/H0 * an integral

As z goes to infinity, t approaches 1/H0. It will never get larger than that.

So the integral must go from 0 to a limit of 1 (rather than infinity).

I could just do this t(z)=1/H0 * -b.
Yes, someone who is truly ignorant of calculus might do that, thinking your Helland equation for t(z) is consistent with Cappi's equation (7).

But your Helland equation for t(z) isn't consistent with Cappi's equation (7). Guessing that the integral is always equal to -b is not at all the same as computing the value of the integral. By the way, the value of the integral in Cappi's equation (7) depends upon several model parameters, including ΩM, ΩR, and ΩΛ.

Your Helland equation for t(z) doesn't mention any of those parameters, so it is freaking obvious that your Helland equation for t(z) is not consistent with Cappi's equation (7).

Originally Posted by Mike Helland View Post
You can call that the blueshift-lookback time relationship if you want.
If you want, you can call it the Helland equation for the blueshift-lookback time relationship.

But you cannot truthfully say your Helland equation for whatever you want to call it is consistent with mainstream equations such as Cappi's equation (7).

Originally Posted by Mike Helland View Post
I can also propose d = -bc / H0, since d=ct.
You are the ultimate authority on Helland physics, so you can propose whatever idiocies you like.

But you cannot truthfully say your proposed idiocies are consistent with mainstream physics.

Last edited by W.D.Clinger; 19th November 2022 at 05:23 AM. Reason: corrected tags so Cappi's equation will be displayed
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Old 19th November 2022, 05:25 AM   #260
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Originally Posted by W.D.Clinger View Post
But you cannot truthfully say your Helland equation for whatever you want to call it is consistent with mainstream equations such as Cappi's equation (7).
You've dubbed one of my equations as the Helland equation.

And then another one of my equations as the Helland equation.

And then you talk about them interchangeably.

I only derived 1/(1+z)=Eobs / Eemit.

I derived the blueshift equation by inverting a mainstream redshift equation.

Those equations are not distance or time relationships.

Those I invented. I modified the broke d=cz/H0 by replacing z with -b: d=-bc/H0.

That wasn't derived. That was just conjectured.

So the different equations came about in different ways.



Quote:
You are the ultimate authority on Helland physics, so you can propose whatever idiocies you like.
Stop being so rude.


Quote:
But you cannot truthfully say your proposed idiocies are consistent with mainstream physics.
How many times are you going to insult me before someone removes your posts?

I didn't say all my equations are consistent with mainstream physics.
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Old 19th November 2022, 05:46 AM   #261
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Originally Posted by Mike Helland View Post
I only derived 1/(1+z)=Eobs / Eemit.

I derived the blueshift equation by inverting a mainstream redshift equation.

Those equations are not distance or time relationships.

Those I invented. I modified the broke d=cz/H0 by replacing z with -b: d=-bc/H0.

That wasn't derived. That was just conjectured.

So the different equations came about in different ways.

Thank you. So far as I know, this is the first time you have actually admitted that your
d=(z/(1+z))(c/H0)
equation was your own invention/conjecture.

Originally Posted by Mike Helland View Post
I didn't say all my equations are consistent with mainstream physics.
The d=(z/(1+z))(c/H0) equation you invented/conjectured was the equation you were using to calculate the distances that, according to you, were a problem for mainstream physics.

If there was a problem with the distances you calculated using an equation you invented/conjectured, that is a problem with Helland physics, not a problem for mainstream physics.

To suggest that the failures of Helland physics are a problem for mainstream physics is dishonest.
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Old 19th November 2022, 05:53 AM   #262
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Originally Posted by W.D.Clinger View Post
Thank you. So far as I know, this is the first time you have actually admitted that your
d=(z/(1+z))(c/H0)
equation was your own invention/conjecture.
I said it straight away.

http://www.internationalskeptics.com...&postcount=126

Quote:
We see now the situation has reversed. Not only does energy and frequency rise when blueshift increases, but all the redshifting happens when -1 < b < 0.

All of z > 0 now fits into -1 < b < 0.

Does that affect anything?

Distance

The z-distance relation is:

d = zc / H0
z << 1

This is only considered valid for very small values of z. At z = 10, the distance would be 140 billion light years. And since z can go up to infinity, the sky is the limit.

How about when redshifts are represented as negative blueshifts (-b) instead of z? Perhaps:

d = -bc / H0
I ask, what can we do with -b? I conjectured a distance relation with it.
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Old 19th November 2022, 06:19 AM   #263
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Originally Posted by Mike Helland View Post
Nope, that is how redshift z is quantified.

Your thinking of the redshift-distance relationship.

If you try to use with d = cz / H0, you will find this equation to be an approximation.

However, by inverting the redshift function, you are multiplying c/H0 by a percentage (rather than to infinity).

Which is what the lookback integral is doing too.
Gibberish.
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Old 19th November 2022, 06:52 AM   #264
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Originally Posted by Mike Helland View Post
No. This is a mainstream physics equation 1+z=Eemit/Eobs.
Really? Link to where you found this please. I think you'll find that you have got that bass ackwards. You end up with negative numbers. Try;

z = Eobs/Eemit -1.
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Old 19th November 2022, 07:13 AM   #265
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Originally Posted by jonesdave116 View Post
Really? Link to where you found this please. I think you'll find that you have got that bass ackwards. You end up with negative numbers.
https://en.wikipedia.org/wiki/Redshift

If the photon is emitted with 1 eV, and observed with 0.5 eV, 1/0.5-1=1.

You would only get negative numbers of emit < observe, but that's blueshift.

Quote:
Try;

z = Eobs/Eemit -1.
That's the inverted formula, which I've been calling b for blueshift to keep separate.

b = Eobs/Eemit -1

If the photon is emitted with 1 eV, and observed with 0.5 eV, 0.5/1-1=-0.5.

So z=1 is equal to b=-0.5.

1+b=1/(1+z)

A CMB photon has a z=1100 and b=-1100/1101=-0.999091.

CMB lookback time is -b/H0.

Last edited by Mike Helland; 19th November 2022 at 07:36 AM. Reason: z=2 to z=1
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Old 19th November 2022, 08:04 AM   #266
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Originally Posted by Mike Helland View Post

And then, three days later, you claimed that equation calculates results that are "exactly equal to LCDM in a default state":
Originally Posted by Mike Helland View Post
It turns out that:



Is exactly equal to LCDM in a default state.

What are the odds of that?

I did not begin to dispute your equation giving d as a function of z until you had claimed your equation was "exactly equal to LCDM in a default state. Here is the first exchange in which I began to discuss your equation:
Originally Posted by Mike Helland View Post
Inconceivable!

So, you're pretty well up to speed on much of this. Does this look familiar at all to you?

Originally Posted by W.D.Clinger View Post
How is that different from
d = (z/(z+1)) c/H0
In other words, why are you writing z/(z+1) as -(1/(1+z)-1) ?

And then you began to say your calculations showed that an "expanding universe is internally inconsistent":
Originally Posted by Mike Helland View Post
This demonstrates that the expanding universe is internally inconsistent.
Originally Posted by W.D.Clinger View Post
No, it doesn't.

In your calculation, a photon with 10 eV at B loses 4 eV to drop to 6 eV by the time it gets to C, while a second photon with 9 eV at B loses 3 eV to drop to the same 6 eV by the time it gets to C. If both events you refer to as B are the same, and both events you refer to as C are the same (which is something we could reasonably assume in a scientific presentation, but all bets are off when the presenter has a long and also recent history of using exactly the same letter to mean completely different things in consecutive sentences), then your calculation is inconsistent with an expanding universe.

That means any conclusions you may attempt to draw from your calculation have nothing to do with an expanding universe.
Originally Posted by Mike Helland View Post
Then what is the proper calculation?

If the calculations are inconsistent with the expanding universe, either the calculations are wrong, or the expanding universe is internally inconsistent.
Originally Posted by W.D.Clinger View Post
Your calculations are wrong. Your calculations are wrong because they are based on Helland physics. Your calculation assumes photons behave as you think they behave, which is not how photons behave according to mainstream physics.

You started out by assuming photons behave in a way that is inconsistent with mainstream physics. It should come as no surprise that such calculations yield results that are inconsistent with mainstream physics. The only conclusion that can be drawn from the inconsistency of your calculation with mainstream physics is that Helland physics is inconsistent with mainstream physics.
Originally Posted by Mike Helland View Post
False.

My calculations are standard mainstream stuff.
Originally Posted by W.D.Clinger View Post
In mainstream relativity and electromagnetism, the following is true:
For any events B and C connected by a specific null geodesic W, and for any photon that departs from B and travels via W to C (without interacting with other particles etc), the relationship between the energy of that photon at B and its energy at C is described by a one-to-one mathematical function.
Your calculation assumes photons violate that fact about mainstream relativity and electromagnetism.

Your calculation is therefore based upon your against-the-mainstream brand of physics, which we might as well refer to as Helland physics.
Originally Posted by Mike Helland View Post
There are no Helland physic here. Just standard redshift and lookback calculations.

Do the math. You won't get different results than I did.

You cannot perform standard redshift or lookback calculations using the equation
d = (z/(1+z))(c/H0)
As you acknowledged an hour or so ago, you invented/conjectured that equation.

ETA: Several posts back, I was trying to get you to tell us the model parameters assumed by your equation above, but you danced and squirmed instead of answering the question. It turns out that if you assume ΩM = ΩR = ΩΛ = 0, then Cappi's equation (7) reduces to t(z) = (1/H0) (z/(1+z)). It seems therefore that your Helland equation for computing d from z assumes a universe devoid of matter, devoid of radiation, and devoid of dark energy. Do you think that explains why your invented/conjectured equation yields calculations that differ from calculations based on mainstream physics, with mainstream estimates of those parameters?

Last edited by W.D.Clinger; 19th November 2022 at 08:18 AM. Reason: added ETA
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Old 19th November 2022, 08:45 AM   #267
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Originally Posted by W.D.Clinger View Post
And then, three days later, you claimed that equation calculates results that are "exactly equal to LCDM in a default state":
Right.

Default as in before you add stuff to it, like matter, dark matter, and dark energy, and give it curvature.


Quote:
ETA: Several posts back, I was trying to get you to tell us the model parameters assumed by your equation above, but you danced and squirmed instead of answering the question. It turns out that if you assume ΩM = ΩR = ΩΛ = 0, then Cappi's equation (7) reduces to t(z) = (1/H0) (z/(1+z)).
http://www.internationalskeptics.com...&postcount=234

Originally Posted by Mike Helland
]And that d = ct, so... those equations must be pretty related

Of course, only when matter doesn't affect redshift and there is no dark energy.
Then I show several comparisons of Cappi's calculator to my equation using various cosmological parameters. Including the empty one being dead on.


Quote:
It seems therefore that your Helland equation for computing d from z assumes a universe devoid of matter, devoid of radiation, and devoid of dark energy. Do you think that explains why your invented/conjectured equation yields calculations that differ from calculations based on mainstream physics, with mainstream estimates of those parameters?
I think it could be, but more to the point, it's testable.

Repulsive dark energy cancels out the effects of attractive matter (including dark matter), but kinda sloppily.

I made this tool to show it, using Cappi's code. Start empty, then add matter, 0.3, then dark energy. Or just read post 234

It seems to me that as distance measurements get better, any discrepancy can be tested by observation.

*edit* forgot link:

https://mikehelland.github.io/hubble...other/lcdm.htm

Last edited by Mike Helland; 19th November 2022 at 08:49 AM.
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Old 19th November 2022, 09:27 AM   #268
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Originally Posted by Mike Helland View Post
Originally Posted by W.D.Clinger View Post
And then, three days later, you claimed that equation calculates results that are "exactly equal to LCDM in a default state":
Right.

Default as in before you add stuff to it, like matter, dark matter, and dark energy, and give it curvature.
But I'm not sure that's right, because...

I logged back in to correct this:
Quote:
ETA: Several posts back, I was trying to get you to tell us the model parameters assumed by your equation above, but you danced and squirmed instead of answering the question. It turns out that if you assume ΩM = ΩR = ΩΛ = 0, then Cappi's equation (7) reduces to t(z) = (1/H0) (z/(1+z)).
Upon checking my integration, I think I left out a factor of 1/2, so I now think Cappi's equation (7) reduces to
t(z) = (1/(2H0)) (z/(1+z))
when you assume ΩM = ΩR = ΩΛ = 0.

Originally Posted by Mike Helland View Post
http://www.internationalskeptics.com...&postcount=234

Originally Posted by Mike Helland
]And that d = ct, so... those equations must be pretty related

Of course, only when matter doesn't affect redshift and there is no dark energy.
Then I show several comparisons of Cappi's calculator to my equation using various cosmological parameters. Including the empty one being dead on.
Well, it's possible I'm mistaken about the factor of 1/2.

Originally Posted by Mike Helland View Post
Quote:
It seems therefore that your Helland equation for computing d from z assumes a universe devoid of matter, devoid of radiation, and devoid of dark energy. Do you think that explains why your invented/conjectured equation yields calculations that differ from calculations based on mainstream physics, with mainstream estimates of those parameters?
I think it could be, but more to the point, it's testable.
I didn't intend to ask a trick question, it just turned out that way.

I'll check my calculation later when I have more time. The integral is greatly simplified by assuming ΩM = ΩR = ΩΛ = 0, but I might have made a mistake while tracing the E(z) of equation (7) back through its defining equation (4) and the definitions preceding equation (4). In particular, I need to check whether the other density parameters really imply Ωk=1 using Cappi's definitions.

As you can imagine, I haven't spent a whole lot of time contemplating the quantitative relationship between redshift and distance in a completely empty universe that, even so, has enough curvature to achieve the critical density.

And by the way, I suspect the calculators you've been using will automatically calculate that curvature parameter from the values you specify for ΩM, ΩR, ΩΛ, and H0. I'm doing this by hand.
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Old 19th November 2022, 09:37 AM   #269
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Originally Posted by W.D.Clinger View Post
And by the way, I suspect the calculators you've been using will automatically calculate that curvature parameter from the values you specify for ΩM, ΩR, ΩΛ, and H0. I'm doing this by hand.
The calculator code I'm using is Cappi's, referenced in the first paragraph:

"This short introduction is extracted from a paper on cosmological models
with a dark energy component (Cappi 2001). For an on–line implementation
of cosmological formulae see www.bo.astro.it/∼cappi/cosmotools."

Code:
Omega_k = 1. - Omega_M - Omega_L;

Last edited by Mike Helland; 19th November 2022 at 09:40 AM.
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Old 21st November 2022, 07:41 AM   #270
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Originally Posted by W.D.Clinger View Post
I'll check my calculation later when I have more time. The integral is greatly simplified by assuming ΩM = ΩR = ΩΛ = 0, but I might have made a mistake while tracing the E(z) of equation (7) back through its defining equation (4) and the definitions preceding equation (4). In particular, I need to check whether the other density parameters really imply Ωk=1 using Cappi's definitions.

As you can imagine, I haven't spent a whole lot of time contemplating the quantitative relationship between redshift and distance in a completely empty universe that, even so, has enough curvature to achieve the critical density.
Does it though?

This calculator shows that k<0 (while Ωk=1).

http://icosmos.co.uk/index.html
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Old 21st November 2022, 09:16 PM   #271
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Originally Posted by Mike Helland View Post
Originally Posted by W.D.Clinger View Post
I'll check my calculation later when I have more time. The integral is greatly simplified by assuming ΩM = ΩR = ΩΛ = 0, but I might have made a mistake while tracing the E(z) of equation (7) back through its defining equation (4) and the definitions preceding equation (4). In particular, I need to check whether the other density parameters really imply Ωk=1 using Cappi's definitions.

As you can imagine, I haven't spent a whole lot of time contemplating the quantitative relationship between redshift and distance in a completely empty universe that, even so, has enough curvature to achieve the critical density.
Does it though?

This calculator shows that k<0 (while Ωk=1).

http://icosmos.co.uk/index.html
k < 0 indicates negative curvature, and Ωk=1 indicates a great deal of curvature. As for the numerical value of k, there are two different conventions.

I haven't looked at that specific calculator, but k is often taken to be a discrete parameter constrained to have one of these three values:
  • k=0 means flat space*
  • k=-1 means space has negative curvature
  • k=+1 means space has positive curvature
That is the convention used in Cappi's paper. With that convention, the scale factor a(t) is the radius of curvature, and is often written R(t) instead of a(t).

I normally use the other common convention, in which a(t) is a dimensionless scale factor expressed as a fraction of the present-day scale, and k is the Gaussian radius of spatial curvature at the present day.

The fact that Cappi's convention is different from the one I tend to use might cause confusion if you're trying to compare my notes on the Friedmann equations for flat space with Cappi's.

*In many of my recent posts, I have written "flat spacetime" when I meant "flat space". Sorry about that.
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Old 21st November 2022, 09:51 PM   #272
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Originally Posted by W.D.Clinger View Post
k < 0 indicates negative curvature, and Ωk=1 indicates a great deal of curvature.
The first part is true.

The second part isn't. Ω indicates ratios in cosmology.
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Old 22nd November 2022, 06:28 AM   #273
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Originally Posted by Mike Helland View Post
Originally Posted by W.D.Clinger View Post
k < 0 indicates negative curvature, and Ωk=1 indicates a great deal of curvature.
The first part is true.
The second part is true as well.

Originally Posted by Mike Helland View Post
The second part isn't. Ω indicates ratios in cosmology.

Ωk is the curvature parameter, defined as the fraction of the critical density by which the sum of the matter, radiation, and dark energy parameters falls short of the critical density. When those other density parameters add up to 1, Ωk=0 and there is no curvature. When all of those other critical densities are 0, Ωk=1, implying a great deal of curvature.

Taking H0=70 km/s/Mpc, Ωk=1 implies the radius of curvature is approximately 140 billion light years. With k=-1, that's a negative curvature, meaning space does not close upon itself, but opens upon itself.

Ωk=1 is hundreds of times more curvature than would be consistent with the Planck mission's observations:
Originally Posted by Wikipedia
Final results of the Planck mission, released in 2018 show the cosmological curvature parameter, 1 – Ω = ΩK = –K c˛/a˛H˛, to be 0.0007±0.0019, consistent with a flat universe.[18] (i.e. positive curvature: K = +1, Ωκ < 0, Ω > 1, negative curvature: K = −1, Ωκ > 0, Ω < 1, zero curvature: K = 0, Ωκ = 0, Ω = 1).
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Old 22nd November 2022, 07:10 AM   #274
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Originally Posted by W.D.Clinger View Post
Ωk is the curvature parameter, defined as the fraction of the critical density by which the sum of the matter, radiation, and dark energy parameters falls short of the critical density.
Right, so when ΩK=1, then it falls short of the critical density by 100%.

You said:

Quote:
As you can imagine, I haven't spent a whole lot of time contemplating the quantitative relationship between redshift and distance in a completely empty universe that, even so, has enough curvature to achieve the critical density.
So we agree it doesn't achieve critical density?

Quote:
1 – Ω = ΩK
http://hyperphysics.phy-astr.gsu.edu...denpar.html#c1

"It is customary to express the density as a fraction of the density required for the critical condition with the parameter Ω = ρ/ρcritical so that Ω = 1 represents the condition of critical density. "

p = 0, so Ω = 0, and ΩK = 1.
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Old 22nd November 2022, 09:09 AM   #275
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Originally Posted by Mike Helland View Post
Originally Posted by W.D.Clinger View Post
Ωk is the curvature parameter, defined as the fraction of the critical density by which the sum of the matter, radiation, and dark energy parameters falls short of the critical density.
Right, so when ΩK=1, then it falls short of the critical density by 100%.
Right, assuming the antecedent of the highlighted pronoun is the sum of the matter, radiation, and dark energy parameters.

Originally Posted by Mike Helland View Post
You said:

Quote:
As you can imagine, I haven't spent a whole lot of time contemplating the quantitative relationship between redshift and distance in a completely empty universe that, even so, has enough curvature to achieve the critical density.
So we agree it doesn't achieve critical density?
Right, assuming the highlighted pronoun refers to the sum of the matter, radiation, and dark energy parameters.

My highlighted phrase was a poor joke, intended to highlight your mistake in this post:
Originally Posted by Mike Helland
Originally Posted by W.D.Clinger View Post
And then, three days later, you claimed that equation calculates results that are "exactly equal to LCDM in a default state":
Right.

Default as in before you add stuff to it, like matter, dark matter, and dark energy, and give it curvature.

The highlighted phrase told me that, when you wrote that, you thought the calculator you were using defaulted to parameters corresponding to a completely empty universe, devoid of matter and devoid of energy, with no curvature.

You were unaware that your calculator automatically supplied enough curvature to make up for the failure of the ordinary density parameters to add up to the critical density.
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Old 22nd November 2022, 09:14 AM   #276
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Originally Posted by W.D.Clinger View Post
Right, assuming the antecedent of the highlighted pronoun is the sum of the matter, radiation, and dark energy parameters.


Right, assuming the highlighted pronoun refers to the sum of the matter, radiation, and dark energy parameters.

My highlighted phrase was a poor joke, intended to highlight your mistake in this post:



The highlighted phrase told me that, when you wrote that, you thought the calculator you were using defaulted to parameters corresponding to a completely empty universe, devoid of matter and devoid of energy, with no curvature.

You were unaware that your calculator automatically supplied enough curvature to make up for the failure of the ordinary density parameters to add up to the critical density.
Ha, I see.

Yeah, it has negative curvature by default.

On a related note, I have a lot of money... if you count having negative money as a lot.
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Old 22nd November 2022, 09:28 AM   #277
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Originally Posted by Mike Helland View Post
Ha, I see.

Yeah, it has negative curvature by default.

On a related note, I have a lot of money... if you count having negative money as a lot.

You didn't really have to convince us you don't understand the concept of curvature in geometry, but I agree about your remarks being good for a laugh.

Originally Posted by Wikipedia
For example, a sphere of radius r has Gaussian curvature 1/r2 everywhere, and a flat plane and a cylinder have Gaussian curvature zero everywhere. The Gaussian curvature can also be negative, as in the case of a hyperboloid or the inside of a torus.

ETA: Here's a picture.

Last edited by W.D.Clinger; 22nd November 2022 at 09:30 AM. Reason: added ETA
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Old 22nd November 2022, 12:11 PM   #278
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Originally Posted by W.D.Clinger View Post
You didn't really have to convince us you don't understand the concept of curvature in geometry, but I agree about your remarks being good for a laugh.

ETA: Here's a picture.
So, an empty FLRW universe only expands, and has an open geometry.

Fill it up with just the right amount of matter (and/or radiation) the expansion and gravity will be in balance, with is flat.

And if it has more matter than that, gravity will overpower expansion and it is closed.

But you could add repulsive dark energy to push it back to flat or open.

So did you figure out how that lookback integral reduces? H0 or 2H0.
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Old 22nd November 2022, 01:22 PM   #279
W.D.Clinger
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Originally Posted by Mike Helland View Post
So, an empty FLRW universe only expands, and has an open geometry.
Not exactly. You apparently do not understand that the FLRW models are an entire family of mathematical models.

One of the FLRW models is for an empty universe with flat space (zero curvature). That's because the general theory of relativity reduces to special relativity.

Because you were playing around with a calculator whose models and parameters you did not understand, you told it to assume a completely empty universe with a positive Hubble constant. (I don't know whether you specified the Hubble constant yourself or let the calculator choose a default positive value for the Hubble constant, but I also don't much care how you screwed up.) With those assumptions, special relativity doesn't apply because of the positive Hubble constant. To accommodate the Hubble constant you specified (whether explicitly or implicitly), the calculator had to assume a lot of negative curvature to account for how you could have that Hubble constant despite empty space.

Originally Posted by Mike Helland View Post
Fill it up with just the right amount of matter (and/or radiation) the expansion and gravity will be in balance, with is flat.
If the matter, radiation, and dark energy densities add up to the critical density, then space will be flat. Note, however, that flat space is entirely consistent with expansion, even with an accelerating expansion, and that is the conclusion to which we are led by observations that imply realistic values for the density parameters.

ETA: By the way, the distinction between flat and curved is not the same as the distinction between open and closed.

Originally Posted by Mike Helland View Post
And if it has more matter than that, gravity will overpower expansion and it is closed.
Well, if it has more matter etc than the critical density, then spacetime is closed in the sense that gravity will eventually overpower expansion, leading to a Big Crunch.

But even that conclusion is based upon the FLRW models, and mainstream cosmologists are willing to consider effects that are not considered by the FLRW models.

Originally Posted by Mike Helland View Post
But you could add repulsive dark energy to push it back to flat or open.
Which is, at the moment, the mainstream explanation for why the universe is flat to within measurement error...

...instead of being hundreds of times more curved than would be consistent with measurements, which is the scenario you hilariously described as "LCDM in a default state".

It took me a while to understand what you were smoking when you wrote that. By the way, I am not suggesting you were being ridiculous on purpose.

Originally Posted by Mike Helland View Post
So did you figure out how that lookback integral reduces? H0 or 2H0.
Within the next couple of days, I hope to finish my calculations and write them up for public consumption at this forum. Inspired by your "LCDM in a default state", I will do the math for your "LCDM in a default state" as well as for a variety of other simple models that are just as far out of touch with reality, mainly because I know how to compute closed form solutions for the integrals that come up when calculating with those simple models. Then I will use numerical integration to do the math for a couple of more realistic models.

I prefer to present all of those calculations within a single long post.

Last edited by W.D.Clinger; 22nd November 2022 at 01:27 PM. Reason: added ETA
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Old 22nd November 2022, 01:43 PM   #280
Mike Helland
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Originally Posted by W.D.Clinger View Post
Within the next couple of days, I hope to finish my calculations and write them up for public consumption at this forum. Inspired by your "LCDM in a default state", I will do the math for your "LCDM in a default state" as well as for a variety of other simple models that are just as far out of touch with reality, mainly because I know how to compute closed form solutions for the integrals that come up when calculating with those simple models. Then I will use numerical integration to do the math for a couple of more realistic models.

I prefer to present all of those calculations within a single long post.
I look forward to it.

The first parameters I compared to my distance relationship were ΩM=0.3 and ΩΛ=0.7.



The blue line shows the difference between them.

Considering I just went "what about quantifying redshift as negative blueshift" and use that in the distance relationship, I was pretty shocked it was actually that close.

So you can imagine that finding they match exactly when you remove the effects of gravity and dark energy was completely not what I was expecting to find.

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