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Old 29th March 2023, 06:19 PM   #1401
Mike Helland
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Originally Posted by W.D.Clinger View Post
Helland physics has given us an entirely new way to misunderstand the universe.
I'm ok with that.

If it's perfectly reasonable to adjust the space coefficients based on the time coordinate:



Then it should be acceptable to make the time coefficient based on the space coordinates.
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Old 29th March 2023, 06:56 PM   #1402
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Details matter.

Tom Knight was one of the lead designers of the MIT Lisp Machines. This story says a lot about the previous post.
A novice was trying to fix a broken Lisp machine by turning the power off and on.

Knight, seeing what the student was doing, spoke sternly: “You cannot fix a machine by just power-cycling it with no understanding of what is going wrong.”

Knight turned the machine off and on.

The machine worked.
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Old 30th March 2023, 06:19 AM   #1403
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Originally Posted by hecd2 View Post
You replied to me in three minutes. You're not stopping to think. No-one apart from you believes that the paradox is anything other than irresolvable. The only thing you have to measure time on is your clock at A, and the round trips of two pulses are different according to that clock. There is no way round that. I'm not starting this again. You can carry on thinking you've resolved it and everyone who knows what they're talking about, including the referee when you submit the embarassing "paper" that you will no doubt write, will tell you the same thing, and you still won't believe them, like you didn't believe the referee on your last "paper". It's a waste of everyone's time.
Originally Posted by Mike Helland View Post
Sure. And in my model, photon 2 arrives late and photon 1 takes off early.
Changing where you start to count does not fix the paradox. It's like adding an extra flywheel to your perpetual motion machine.
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Old 30th March 2023, 08:57 AM   #1404
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Originally Posted by Mike Helland View Post
You said "you" thirteen times in seven sentences.
To paraphrase from here:
https://despair.com/products/dysfunction
The only consistent feature in all your failed theories is you. That's why I'm emphasizing you. The details of an individual failure are pretty secondary, far more significant is the consistent cause of those failures, and that's you. So you deserve attention, because that's the only possible source for a fix to any of this. Not tweaking your theory with yet another revision, but a fundamental change in how you approach everything. You need to start by learning, and not in this half-assed way you're currently doing it.

Quote:
I've always done calculus problems with a computer program and a lot of trial and error. I know that's severely limiting. (No pun intended.) But it usually gets the right enough answers.

I just don't understand why it won't fly.

Quote:
And based on your feedback over the last couple years, I have revisited calculus, to try to express it in the calculus way, but obviously not well enough. I went over linear algebra too, and a couple other things.
Indeed, it's not enough. Not close to enough. There's a reason people spend year and years just learning this stuff, before they even try to do something new.

Quote:
You were also the one that said photons can't lose frequency without clocks desynchronizing, which is why we're talking about dynamic time in the first place.
I did indeed say that, and it is indeed true. But you seem to think that desynchronizing clocks is some trivial thing. It's not. It is no small feat to develop a new theory of desynchronization in a manner that is self-consistent, let alone in a manner that is consistent with observations. The parts need to connect to make a self-consistent whole, and you're not doing that. It is beyond you. Hell, it's beyond me too. The difference is that I know I'm not up to the task, despite knowing far more math and physics than you. For some reason, and despite all evidence to the contrary, you think you are. You are not.

Quote:
Regarding the first, one example was the flight time paradox, I think that's resolved:
No, it isn't resolved. You've got hand waving nonsense about dynamic time that doesn't actually make any sense. You have no coherent picture of what your dynamic time actually is, or what it actually does.

Quote:
As far as expressing it in the framework of relativity, I don't think I'm that far off in thinking that could be in the form of a metric tensor that reduces to the Minkowski metric at less than cosmological scales. And that it makes a "v" look like a "u".
You seem to think that means something. It doesn't.
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Old 30th March 2023, 09:07 AM   #1405
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Originally Posted by Mike Helland View Post
I'm ok with that.

If it's perfectly reasonable to adjust the space coefficients based on the time coordinate:

https://math-demo.abitti.fi/math.svg...d%7Bpmatrix%7D

Then it should be acceptable to make the time coefficient based on the space coordinates.
The Robertson-Walker metric is for an isotropic homogeneous Universe. In such a Universe, time passes at the same rate at all locations. You can write a 3 dimensional spatial metric for a given time which describes the intrinsic curvature and other properties, such as distances between points and angles between lines which are invariant under coordinate transformations.

If the rate of time is a function of location then the Universe is no longer homogeneous. But the Universe appears to us to be the same in all directions. The only way that can be is if the non-homogeneous Universe is spherically symmetric with us at its centre. That would make you a geocentrist. Is that what you arguing for?
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Old 30th March 2023, 09:54 AM   #1406
Mike Helland
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Originally Posted by Mashuna View Post
Changing where you start to count does not fix the paradox.
That's not quite what I'm suggesting.

Time dilation makes durations longer. Whether that duration extends to the future, or the past, shouldn't make a difference.
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Old 1st April 2023, 01:28 PM   #1407
Mike Helland
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Originally Posted by W.D.Clinger View Post
\
\According to the theory of relativity, light follows null geodesics. Analyzing Mike Helland's two guesses at a metric, that means light travels slower (according to his first guess) as x approaches the coordinate singularity than at x = 0 or negative values of x, or light travels faster (according to his second guess) as x approaches the coordinate singularity.
If dynamic time is something like:



Why do you say that changes the speed of light?

More importantly, why doesn't something similar happen when you stretch space:

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Old 2nd April 2023, 12:16 AM   #1408
Mike Helland
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Originally Posted by Mike Helland View Post
If dynamic time is something like:

https://latex.codecogs.com/png.image...\\end{bmatrix}

Why do you say that changes the speed of light?

More importantly, why doesn't something similar happen when you stretch space:

https://math-demo.abitti.fi/math.svg...A\end{pmatrix}
https://arxiv.org/abs/1804.10047

"At redshift z, the vacuum speed of light in comoving coordinates is a−1c = (1 + z)c"
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Old 2nd April 2023, 01:39 AM   #1409
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time line of another bad idea

So I call these things Cargo Cult Science, because they follow all the apparent precepts and forms of scientific investigation, but they're missing something essential, because the planes don't land.

—Richard Feynman (1974 commencement address at Caltech)
Today is 2 April.

Originally Posted by Mike Helland View Post
If dynamic time is something like:

https://latex.codecogs.com/png.image...\\end{bmatrix}
Details matter.

That's why I analyzed two of Mike Helland's specific wrong guesses about a metric form for Helland physics, relying on Mike Helland's explicit description of his coordinates: His unit for the time coordinate is a million years, and his unit for spatial coordinates is a million light years.

My specific analyses of Mike Helland's two specific wrong guesses do not generalize to "something like" the highly abstracted metric form he wrote above.

Originally Posted by Mike Helland View Post
Why do you say that changes the speed of light?
Because, knowing his specified coordinates, I know how to analyze Mike Helland's specific wrong guesses.

Originally Posted by Mike Helland View Post
More importantly, why doesn't something similar happen when you stretch space:

https://math-demo.abitti.fi/math.svg...A\end{pmatrix}
Something does happen, but it would be a stretch to say it's something similar.

I'll be happy to explain this stuff to Mike Helland, after he learns the relevant mathematics.

For most people, it takes several years to learn enough calculus, linear algebra, topology, and differential geometry to understand general relativity and the variety of metric forms that describe various spacetime manifolds. Truth be told, most people never learn enough math to understand general relativity, so his own failure to understand doesn't make him special.
The first principle is that you must not fool yourself—and you are the easiest person to fool.

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Old 2nd April 2023, 01:56 AM   #1410
Mike Helland
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Originally Posted by W.D.Clinger View Post
Something does happen, but it would be a stretch to say it's something similar.
If the speed of light in comoving coordinates is c(1+z):

c < femit * wemit * (1+z)

c < femit * wobs
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Old 2nd April 2023, 02:34 AM   #1411
W.D.Clinger
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yet another example of the cargo cult

Originally Posted by Mike Helland View Post
https://arxiv.org/abs/1804.10047

"At redshift z, the vacuum speed of light in comoving coordinates is a−1c = (1 + z)c"
From that very same paper:
Quote:
The vacuum speed of light c is invariant...
To reconcile those two statements, Mike Helland will have to learn that the map is not the territory.

By the way, the equation
a−1c = (1 + z)c
is an immediate consequence of the equation
a−1 = (1 + z)
which is an immediate consequence of the mainstream equation
1 + z = a(t0) / a(t1)
(where t1 is the time at which the redshifted photon was emitted, and t0 is the present time) because a(t0) = 1 by convention.

Originally Posted by Wojtak and Prada
The canonical redshift–scale factor relation, 1/a = 1 + z, is a key element in the standard Λ cold dark matter (ΛCDM) model of the big bang cosmology.
As that paper points out, 1/a = 1 + z is a consequence of FLRW models that describe an expanding universe, and does not necessarily hold in non-FLRW models.

In particular, Helland physics insists the universe is not expanding, which implies a(t1) = 1, from which the equation quoted by Mike Helland implies z = 0. Helland physics is not based on an FLRW model, however, so Helland physics is not constrained by the equation Mike Helland quoted. It is of course completely unclear why Mike Helland quoted that equation, apart from his habit of randomly quoting things he finds online in the hope some readers will make the mistake of assuming his random quotations of real science somehow transform the cargo cult we refer to as Helland physics into real science.

For an example of that behavior, see what Mike Helland wrote a little more than half an hour ago.

Last edited by W.D.Clinger; 2nd April 2023 at 03:52 AM. Reason: added link to final sentence; corrected a subscript
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Old 2nd April 2023, 02:50 AM   #1412
Mike Helland
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Originally Posted by W.D.Clinger View Post
It is of course completely unclear why Mike Helland quoted that equation
Seems pretty clear to me.

I asked if the FLRW metric meant that stretching space resulted in a faster speed of light.

Seems like it does.

v = c(1+z)

1+z = v / c

We also know v > c, so v = c + v2, where v2 > 0.

That seems to be copacetic with relativity, so my derivation should be ok with it too.

The metric I'm suggesting simply changes the rubber ruler for a lazy clock.
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Old 2nd April 2023, 03:01 AM   #1413
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Quoting here for the record, to protect against the possibility of subsequent edits:

Originally Posted by Mike Helland View Post
https://arxiv.org/abs/1804.10047

"At redshift z, the vacuum speed of light in comoving coordinates is a−1c = (1 + z)c"
Originally Posted by Mike Helland View Post
If the speed of light in comoving coordinates is c(1+z):

c < femit * wemit * (1+z)

c < femit * wobs

Assuming z > 0, that first inequality doesn't have anything to do with comoving coordinates because it is equivalent to
c < c * (1 + z)
The second inequality also doesn't have anything to do with the speed of light in comoving coordinates.

The two posts quoted above tell us Mike Helland doesn't have a clue about comoving coordinates. But we could have guessed that.

ETA: I'm going to let others respond to the nonsense Mike Helland wrote immediately above. Why should I have all the fun?

Last edited by W.D.Clinger; 2nd April 2023 at 03:14 AM. Reason: added ETA
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Old 2nd April 2023, 03:49 AM   #1414
Mike Helland
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Originally Posted by W.D.Clinger View Post
Assuming z > 0, that first inequality doesn't have anything to do with comoving coordinates because it is equivalent to
c < c * (1 + z)
The second inequality also doesn't have anything to do with the speed of light in comoving coordinates.

The two posts quoted above tell us Mike Helland doesn't have a clue about comoving coordinates. But we could have guessed that.
This first link in your chronology is:

http://www.internationalskeptics.com...6#post14033386

Originally Posted by hecd2
Therefore Helland physics violates SR.

Originally Posted by Mike Helland View Post
If you say so.

The first model is the expanding universe, which isn't Helland physics. The second model is the decelerating photon, which isn't Helland physics.

The third model is the one I find most interesting, where distant clocks run slower.

The Minkowski metric is:

Code:
-1000
 0100
 0010
 0001
https://mathworld.wolfram.com/MinkowskiMetric.html

The -1 is the t coordinate. What happens to spacetime when that isn't 1?
So, my derivation included the line:

1+z = (c + v) / c

Does that violate special relativity?

Let's say it does.

But in an expanding universe according to general relativity, that the speed of light is greater than c when z>0 seems to be a given.

We wouldn't say that general relativity violates special relativity.

So it seems the dynamic time conjecture can still operate in the framework of relativity as an alternative to the FLRW metric.
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Old 2nd April 2023, 05:39 AM   #1415
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Originally Posted by Mike Helland View Post

So it seems the dynamic time conjecture can still operate in the framework of relativity as an alternative to the FLRW metric.
Leaving aside all the misunderstandings about tensor algebra that you demonstrate so clearly in your cargo cult posts, I pointed out to you that a metric in which the rate of time is a function of location (unlike FLRW which is based on a homogeneous, isotropic Universe where the gravitational potential, the mass-energy density and the pressure are uniform) would demand that we live in the centre of the Universe - and you ignored me. Are you a geocentrist?
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Old 2nd April 2023, 09:26 AM   #1416
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Originally Posted by hecd2 View Post
Leaving aside all the misunderstandings about tensor algebra that you demonstrate so clearly in your cargo cult posts, I pointed out to you that a metric in which the rate of time is a function of location (unlike FLRW which is based on a homogeneous, isotropic Universe where the gravitational potential, the mass-energy density and the pressure are uniform) would demand that we live in the centre of the Universe - and you ignored me. Are you a geocentrist?
I did notice your attempt to change the subject.

"If the rate of time is a function of location then the Universe is no longer homogeneous."

Is it?

The rate at which galaxies move apart is a function of distance, and causes clocks to move slower. That's homogeneous? Seems like your definition is pretty arbitrary.

You say the universe is observed to homogeneous. Is it?

https://en.wikipedia.org/wiki/Lambda...of_homogeneity

Quote:
Based on N-body simulations in ΛCDM, Yadav and his colleagues showed that the spatial distribution of galaxies is statistically homogeneous if averaged over scales 260/h Mpc or more.[44] However, many large-scale structures have been discovered, and some authors have reported some of the structures to be in conflict with the predicted scale of homogeneity for ΛCDM, including

The Clowes–Campusano LQG, discovered in 1991, which has a length of 580 Mpc
The Sloan Great Wall, discovered in 2003, which has a length of 423 Mpc,[45]
U1.11, a large quasar group discovered in 2011, which has a length of 780 Mpc
The Huge-LQG, discovered in 2012, which is three times longer than and twice as wide as is predicted possible according to ΛCDM
The Hercules–Corona Borealis Great Wall, discovered in November 2013, which has a length of 2000–3000 Mpc (more than seven times that of the SGW)[46]
The Giant Arc, discovered in June 2021, which has a length of 1000 Mpc[47]

Other authors claim that the existence of structures larger than the scale of homogeneity in the ΛCDM model does not necessarily violate the cosmological principle in the ΛCDM model.[48][13]
Our latest assumption is that the universe is homogeneous at scales beyond which we actually observe.

That's the direction you want to go with this?

I take it you realized it's not internally inconsistent, and that it can be relativistic (and I take it you'll deny that up and down) hence resorting to a more dubious argument involving the cosmological principle.
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Old 2nd April 2023, 10:15 AM   #1417
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Seven hours ago, I wrote:
Originally Posted by W.D.Clinger View Post
ETA: I'm going to let others respond to the nonsense Mike Helland wrote immediately above. Why should I have all the fun?
But I'm going to have a little fun here because Mike Helland's subsequent post made his obvious confusion even clearer.

Someone who doesn't know the difference between a map and the territory might look at a Mercator projection and conclude Greenland is the same size as Africa.

People who know enough to distinguish the map from the territory will say instead that the Mercator projection gives Greenland as much space on the map as it gives to Africa, but in reality Africa is about 14 times as large as Greenland.

The Mercator projection is great when you want to keep track of true north and south, and when you want the mapped shapes of land masses to approximate their real shapes, but it's quite misleading when what you care about is the areas of those land masses.

Mike Helland has consistently failed to distinguish maps from territories. The two quotations below are just the most recent examples of his confusion.

As background, consider this metric form for isotropic flat space in Cartesian coordinates:
ds2 = – c2 dt2 + a(t)2 dx2 + a(t)2 dy2 + a(t)2 dz2
Although that metric form is often called the FLRW metric, it is considerably more general; it expresses the metric of any isotropic flat spacetime. (To obtain an FLRW model, you combine that metric form with assumptions about the cosmological constant and the tensor on the right hand side of the Einstein field equations.)

The comoving coordinates that appear within that metric form are <t, x, y, z>.

In what follows, keep in mind that although the actual speed of light in vacuo is invariant, the coordinate-dependent speed of light depends upon the coordinates you're using.

To calculate the coordinate-dependent speed of light in those comoving coordinates, consider a photon moving through a vacuum along the x axis at some time t. Photons follow null geodesics, so
0 = – c2 dt2 + a(t)2 dx2
High school algebra then tells us

c2 dt2 = a(t)2 dx2
c2 / a(t)2 = dx2 / dt2
dx/dt = c / a(t)

That is the comoving coordinate velocity of the photon. We can rewrite that equation as
c = a(t) dx / dt
which says the true velocity of light is obtained by multiplying the coordinate-dependent velocity by the scale factor.

Which makes perfect sense if you understand comoving coordinates. A comoving object is an object following a geodesic that preserves its view of the universe as isotropic. In an expanding universe, the distance between comoving objects increases as the universe expands. The comoving coordinates x, y, and z ignore that. By ignoring the time-dependent scale factor a(t), the comoving coordinates essentially pretend a comoving object has always had and always will have the same coordinates x, y, and z that place it at a distance (as of today!) of sqrt(x2 + y2 + z2) from the (arbitrary) origin of the spatial coordinates.

So comoving coordinates are convenient for calculations that need to keep track of the spatial coordinates of comoving objects, because their comoving spatial coordinates don't change over time. When you need to calculate actual distances and velocities, however, you have to take the scale factor into account.

Assuming the coordinate-dependent speed of light in comoving coordinates is the actual speed of light is like assuming the area of a Mercator projection devoted to land masses such as Greenland and Africa accurately quantifies the relative areas of those land masses. It's a novice's mistake.

So Mike Helland made that mistake, and based everything he wrote in the quotations below upon that error.

Originally Posted by Mike Helland View Post
Seems pretty clear to me.

I asked if the FLRW metric meant that stretching space resulted in a faster speed of light.

Seems like it does.

v = c(1+z)

1+z = v / c

We also know v > c, so v = c + v2, where v2 > 0.

That seems to be copacetic with relativity, so my derivation should be ok with it too.

The metric I'm suggesting simply changes the rubber ruler for a lazy clock.
Originally Posted by Mike Helland View Post
This first link in your chronology is:

http://www.internationalskeptics.com...6#post14033386



So, my derivation included the line:

1+z = (c + v) / c

Does that violate special relativity?

Let's say it does.

But in an expanding universe according to general relativity, that the speed of light is greater than c when z>0 seems to be a given.

We wouldn't say that general relativity violates special relativity.

So it seems the dynamic time conjecture can still operate in the framework of relativity as an alternative to the FLRW metric.

Last edited by W.D.Clinger; 2nd April 2023 at 10:23 AM. Reason: minor corrections
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Old 2nd April 2023, 10:42 AM   #1418
Mike Helland
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Originally Posted by W.D.Clinger View Post
Someone who doesn't know the difference between a map and the territory might look at a Mercator projection and conclude Greenland is the same size as Africa.
This is pretty unrelated, but I always like to point out that Greenland is closer in size to Mexico, and then show people this website:

https://thetruesize.com/

Quote:
Mike Helland has consistently failed to distinguish maps from territories. The two quotations below are just the most recent examples of his confusion.

As background, consider this metric form for isotropic flat space in Cartesian coordinates:
ds2 = – c2 dt2 + a(t)2 dx2 + a(t)2 dy2 + a(t)2 dz2
Although that metric form is often called the FLRW metric, it is considerably more general; it expresses the metric of any isotropic flat spacetime. (To obtain an FLRW model, you combine that metric form with assumptions about the cosmological constant and the tensor on the right hand side of the Einstein field equations.)

The comoving coordinates that appear within that metric form are <t, x, y, z>.

In what follows, keep in mind that although the actual speed of light in vacuo is invariant, the coordinate-dependent speed of light depends upon the coordinates you're using.

To calculate the coordinate-dependent speed of light in those comoving coordinates, consider a photon moving through a vacuum along the x axis at some time t. Photons follow null geodesics, so
0 = – c2 dt2 + a(t)2 dx2
High school algebra then tells us

c2 dt2 = a(t)2 dx2
c2 / a(t)2 = dx2 / dt2
dx/dt = c / a(t)

That is the comoving coordinate velocity of the photon. We can rewrite that equation as
c = a(t) dx / dt
which says the true velocity of light is obtained by multiplying the coordinate-dependent velocity by the scale factor.

Ok. So are you saying:



Where f(L) = -(1 - HL2), makes the speed of light slower in that coordinate system?
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Old 2nd April 2023, 11:08 AM   #1419
W.D.Clinger
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Originally Posted by Mike Helland View Post
Ok. So are you saying:

https://latex.codecogs.com/png.image...\\end{bmatrix}

Where f(L) = -(1 - HL2), makes the speed of light slower in that coordinate system?
I have never said that. Until now, you have never even hinted at what f(L) might be in that matrix. Even now, you have not even hinted at what L might be.

And while I would ordinarily assume H is the Hubble parameter, which changes over time, you have insisted that the Hubble parameter does not change over time, and you have responded to irrefutable proofs that Helland physics requires the Hubble parameter to be zero by saying those proofs depend upon the Hubble parameter having the meaning it has in mainstream science. In Helland physics, you are using H to stand for something altogether different, something we might call the Helland parameter. And you have never given us any quantifiable indication of what the Helland parameter might be.

So I'd be a fool to take your f(L) = -(1 - HL2) seriously, inasmuch as it contains two distinct letters whose meaning you have left completely undefined.

Last edited by W.D.Clinger; 2nd April 2023 at 11:17 AM. Reason: added link
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Old 2nd April 2023, 11:34 AM   #1420
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Originally Posted by W.D.Clinger View Post
I have never said that. Until now, you have never even hinted at what f(L) might be in that matrix. Even now, you have not even hinted at what L might be.

And while I would ordinarily assume H is the Hubble parameter, which changes over time, you have insisted that the Hubble parameter does not change over time, and you have responded to irrefutable proofs that Helland physics requires the Hubble parameter to be zero by saying those proofs depend upon the Hubble parameter having the meaning it has in mainstream science. In Helland physics, you are using H to stand for something altogether different, something we might call the Helland parameter. And you have never given us any quantifiable indication of what the Helland parameter might be.

So I'd be a fool to take your f(L) = -(1 - HL2) seriously, inasmuch as it contains two distinct letters whose meaning you have left completely undefined.
Fair enough.

I usually write H0 instead of just H but that was a slip.

L should be:

L2 = dx2 + dy2 + dz2
I guess the desired effect is:

c2 = L2 / (f(L)2 * dt2)

f(L)2 c2 dt2 = L2

0 = - f(L)2 c2 dt2 + dx2 + dy2 + dz2
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Old 2nd April 2023, 11:39 AM   #1421
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Originally Posted by Mike Helland View Post
Ok. So are you saying:

https://latex.codecogs.com/png.image...\\end{bmatrix}

Where f(L) = -(1 - HL2), makes the speed of light slower in that coordinate system?
How do you think you determine the speed of light from a metric tensor? This is actually a non-trivial question. You probably think you know the answer, but you probably do not actually know it.
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Old 2nd April 2023, 12:27 PM   #1422
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Originally Posted by Ziggurat View Post
How do you think you determine the speed of light from a metric tensor? This is actually a non-trivial question. You probably think you know the answer, but you probably do not actually know it.
Is it what W.D.Clinger wrote today, that culminates with: c = a(t) dx / dt ?



That's for dynamic space. So the dynamic time analog would be:



Or is it something else?
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Old 2nd April 2023, 12:36 PM   #1423
W.D.Clinger
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more cargo cultism

Originally Posted by Mike Helland View Post


Where f(L) = -(1 - HL2), makes the speed of light slower in that coordinate system?
Originally Posted by Mike Helland View Post
I usually write H0 instead of just H but that was a slip.

L should be:

L2 = dx2 + dy2 + dz2

Then you are posting gibberish. You haven't said anything about the units you're using now, but H0 has units of inverse time and L2 has units of area (i.e. length squared), so your f(L) = -(1 - HL2) subtracts something with units area/time from the dimensionless constant 1, which probably yields a negative number, which you negate, thereby most likely yielding a non-Lorentzian metric form.

You really and truly have absolutely no idea of what you're doing.

Originally Posted by Mike Helland View Post
I guess the desired effect is:

c2 = L2 / (f(L)2 * dt2)

f(L)2 c2 dt2 = L2

0 = - f(L)2 c2 dt2 + dx2 + dy2 + dz2
Oh dear. Oh dear.

Your
f(L)2 c2 dt2 = L2
can be rewritten as
dt2 = L2 / (f(L)2 c2)
which says dt is a pure function of the location (via L and f(L)) independently of dx, dy, or dz.

That's a truly impressive pile of ackamarackus you dumped there.

Last edited by W.D.Clinger; 2nd April 2023 at 12:38 PM. Reason: parentheses
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Old 2nd April 2023, 12:52 PM   #1424
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Originally Posted by W.D.Clinger View Post
Then you are posting gibberish. You haven't said anything about the units you're using now, but H0 has units of inverse time and L2 has units of area (i.e. length squared), so your f(L) = -(1 - HL2) subtracts something with units area/time from the dimensionless constant 1, which probably yields a negative number, which you negate, thereby most likely yielding a non-Lorentzian metric form.
H0 has units of distance / time / distance.

L2 is a mistake. The 2 should be outside the parenthesis. And that too might be a mistake. Because:

Quote:
You really and truly have absolutely no idea of what you're doing.
To be fair, I think I have 0.0000756% of a clue. It ain't much, I'll give you that.

Quote:
Oh dear. Oh dear.

Your
f(L)2 c2 dt2 = L2
can be rewritten as
dt2 = L2 / (f(L)2 c2)
which says dt is a pure function of the location (via L and f(L)) independently of dx, dy, or dz.
Hmmm. Is that because I used L instead of dL? Should it be:

dL2 = dx2 + dy2 + dz2
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Old 2nd April 2023, 01:14 PM   #1425
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Originally Posted by W.D.Clinger View Post
which says dt is a pure function of the location (via L and f(L)) independently of dx, dy, or dz.
Not sure what you mean.

L is just short hand for:



If what you said before:



Then:



Isn't that analogous?
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Old 2nd April 2023, 01:31 PM   #1426
W.D.Clinger
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Originally Posted by Mike Helland View Post
Originally Posted by W.D.Clinger View Post
Then you are posting gibberish. You haven't said anything about the units you're using now, but H0 has units of inverse time and L2 has units of area (i.e. length squared), so your f(L) = -(1 - HL2) subtracts something with units area/time from the dimensionless constant 1, which probably yields a negative number, which you negate, thereby most likely yielding a non-Lorentzian metric form.
H0 has units of distance / time / distance.


FYI: "units of distance / time / distance" is just a complicated way to say units of inverse time.

Originally Posted by Mike Helland View Post
L2 is a mistake. The 2 should be outside the parenthesis.
Moving the exponent outside the parenthesis doesn't fix anything. In one important sense that I explained to you a couple of weeks ago, it actually makes things worse. But you ignored me then, because you don't know enough high school algebra and calculus to understand even the simplest explanations of what you're doing wrong.

Originally Posted by Mike Helland View Post
Hmmm. Is that because I used L instead of dL? Should it be:

dL2 = dx2 + dy2 + dz2
Actually, I misread your definition of L as L2 = x2 + y2 + z2. You are correct, however, that writing L instead of dL led me to jump to the conclusion that there were no differentials on the right hand side either.

Originally Posted by Mike Helland View Post
Not sure what you mean.

L is just short hand for:



If what you said before:



Then:



Isn't that analogous?
See above.

Please take note, however, that your gibberish has quite a few other obvious problems that I haven't mentioned and probably won't ever bother to mention. There's no use.
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Old 2nd April 2023, 01:42 PM   #1427
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Originally Posted by W.D.Clinger View Post


FYI: "units of distance / time / distance" is just a complicated way to say units of inverse time.
Yes, very true.

It's just a different way to follow the units.

distance/time/distance = velocity / distance

So in Hubble's law, v = H0d, you get

velocity = velocity / distance * distance

Rather than using natural units (c=1), the coefficient for the time coordinate should be:

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Old 2nd April 2023, 02:59 PM   #1428
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Originally Posted by Mike Helland View Post
Is it what W.D.Clinger wrote today, that culminates with: c = a(t) dx / dt ?



That's for dynamic space. So the dynamic time analog would be:



Or is it something else?
I was asking how to do it in general, given a metric tensor. If you are asking if that's the right answer, then you don't know, and if you don't know, you don't understand any of what you're talking about. This isn't news, but you're acting like you think you are on the cusp of understanding and you aren't. You don't have the foundation necessary to understand any of the answers you are being given.
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Old 2nd April 2023, 03:13 PM   #1429
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This is what cargo cult physics looks like. Just within the past day or so, Mike Helland has made at least five different wild guesses (in the spoiler) concerning what he guesses he hopes to be a plausible metric form for Helland physics.

Originally Posted by Mike Helland View Post
Ok. So are you saying:



Where f(L) = -(1 - HL2), makes the speed of light slower in that coordinate system?
Originally Posted by Mike Helland View Post
I usually write H0 instead of just H but that was a slip.

L should be:

L2 = dx2 + dy2 + dz2
I guess the desired effect is:

c2 = L2 / (f(L)2 * dt2)

f(L)2 c2 dt2 = L2

0 = - f(L)2 c2 dt2 + dx2 + dy2 + dz2
Originally Posted by Mike Helland View Post


That's for dynamic space. So the dynamic time analog would be:



Or is it something else?
Originally Posted by Mike Helland View Post
L2 is a mistake. The 2 should be outside the parenthesis.
Originally Posted by Mike Helland View Post
Rather than using natural units (c=1), the coefficient for the time coordinate should be:

What a mess.

I sincerely hope Mike Helland will clean up that mess by giving us just one last guess at a metric form, complete with a description of its coordinates and units, so we can have one last laugh before turning to the next chapter of this cargo cult physics.
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Old 2nd April 2023, 03:30 PM   #1430
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Originally Posted by W.D.Clinger View Post
I sincerely hope Mike Helland will clean up that mess by giving us just one last guess at a metric form, complete with a description of its coordinates and units, so we can have one last laugh before turning to the next chapter of this cargo cult physics.
Ok. Well, the lookback time for an FLRW universe with ΩΛ=1 is:



It gives the right graph when I plot this:

https://www.wolframalpha.com/input?i...%2Bx%5D%2Cx%5D

So that should give the coordinate time.

Whereas the "true" or "actual" time as you put it is L/c.
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Old 2nd April 2023, 03:57 PM   #1431
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ackamarackus

Originally Posted by Mike Helland View Post
Originally Posted by W.D.Clinger View Post
I sincerely hope Mike Helland will clean up that mess by giving us just one last guess at a metric form, complete with a description of its coordinates and units, so we can have one last laugh before turning to the next chapter of this cargo cult physics.
Ok. Well, the lookback time for an FLRW universe with ΩΛ=1 is:



It gives the right graph when I plot this:

https://www.wolframalpha.com/input?i...%2Bx%5D%2Cx%5D

So that should give the coordinate time.

Whereas the "true" or "actual" time as you put it is L/c.
So that is Mike Helland's very best guess at what the metric form for Helland physics should look like.

Mike Helland's very best guess at the metric form for Helland physics does not resemble a metric form in any way.

But that's the very best he can do: quoting some random thing he found on the World-Wide Web, hoping it will fool some readers into thinking it has some remote relevance to the issue at hand.
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Old 2nd April 2023, 05:27 PM   #1432
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Originally Posted by Mike Helland View Post
I did notice your attempt to change the subject.
How on earth is it a change of subject to point out to you that your silly attempts to write down a metric tensor with a function of location in g00 results in a description of a non-homogeneous Universe. We observe the Universe to be isotropic. The only way that we can combine observed isotropy with inhomogeneity is if the Universe is spherically symmetric with us at its centre. (For example the Schwarzschild solution is spherically symmetric but not homogeneous).

Quote:
"If the rate of time is a function of location then the Universe is no longer homogeneous."

Is it?
Absolutely. The Robertson-Walker metric describes a homogeneous isotropic Universe (and is provably the only metric for a homogeneous isotropic Universe). In the FLRW solution the proper time is the same at all locations for comoving observers (so, for example, things which are functions of time, for example the scale factor, are universal and do not vary by location)
Quote:
The rate at which galaxies move apart is a function of distance, and causes clocks to move slower. That's homogeneous? Seems like your definition is pretty arbitrary.
You are confusing proper time with coordinate time.

Quote:
You say the universe is observed to homogeneous. Is it?

https://en.wikipedia.org/wiki/Lambda...of_homogeneity
I said the Universe appears to be the same in all directions - ie we observe it to be isotropic. For example the CMB is uniform to one part in 100,000. If the Universe is isotropic but inhomogeneous it must be spherically symmetric with us at the centre.
Quote:
I take it you realized it's not internally inconsistent, .
Your utterly daft idea that light pulses travelling the same distance at the same speed can have a different round trip flight time is totally inconsistent and FUBAR. You have been told that over and over again, but you are too ignorant and arrogant to accept it.
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Old 2nd April 2023, 05:58 PM   #1433
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Originally Posted by hecd2 View Post
How on earth is it a change of subject to point out to you that your silly attempts to write down a metric tensor with a function of location in g00 results in a description of a non-homogeneous Universe.
Let's say you have a fish pond. In the middle the fish are relatively still. But as you increase toward the edges, the fish are progressively more active and swimming faster.

Is the pond homogeneous?
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Old 2nd April 2023, 06:16 PM   #1434
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Originally Posted by W.D.Clinger View Post
So that is Mike Helland's very best guess at what the metric form for Helland physics should look like.
Well it would be (and point out any mistakes, cause I'm sure there are some):

So:

Earlier I said:

But that's in terms of z, and probably needs to be in terms of L.

This also calculates lookback time:

So that's what should be in place of f(L).

Last edited by Mike Helland; 2nd April 2023 at 06:17 PM.
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Old 3rd April 2023, 02:23 AM   #1435
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Originally Posted by Mike Helland View Post
Let's say you have a fish pond. In the middle the fish are relatively still. But as you increase toward the edges, the fish are progressively more active and swimming faster.

Is the pond homogeneous?
No, it would be inhomogeneous and isotropic about the centre. And your point is?


ETA: for a fish living in such a pond, the only way that things would appear to be the same in all directions (isotropic) is if it was at the centre.
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Old 3rd April 2023, 02:44 AM   #1436
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Originally Posted by Mike Helland View Post
Well it would be (and point out any mistakes, cause I'm sure there are some):

So:

Earlier I said:

But that's in terms of z, and probably needs to be in terms of L.

This also calculates lookback time:

So that's what should be in place of f(L).
Others have already pointed out that in Helland physics H0 = H(t) = 0 (that's precisely what a static Universe means). So your integral where is a constant of integration.
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Old 3rd April 2023, 05:40 AM   #1437
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Originally Posted by hecd2 View Post
Others have already pointed out that in Helland physics H0 = H(t) = 0 (that's precisely what a static Universe means). So your integral where is a constant of integration.
That ol' strawman.

H0 is a measured constant in Helland physics.

The FLRW model to which it is analogous is ΩΛ=1.

H(t) / H0 = E(z)

Which is 1 for the ΩΛ plus 0 for ΩM and ΩR.

H0 = Ht

Because the constant doesn't change in that model, that's why its dobs exactly matches d=zc/H0 and demit exactly matches d=z/(1+z) * c/H0.

FWIW, it should be:

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Old 3rd April 2023, 06:12 AM   #1438
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Originally Posted by Mike Helland View Post
That ol' strawman.

H0 is a measured constant in Helland physics.

The FLRW model to which it is analogous is ΩΛ=1.

H(t) / H0 = E(z)

Which is 1 for the ΩΛ plus 0 for ΩM and ΩR.

H0 = Ht

Because the constant doesn't change in that model, that's why its dobs exactly matches d=zc/H0 and demit exactly matches d=z/(1+z) * c/H0.

What Mike Helland wrote above implies
a(t) = eH0t
In other words, Mike Helland is saying that, in Helland physics, the size of the universe increases exponentially with time.

But Mike Helland doesn't know enough mathematics to realize he's saying that, and will undoubtedly respond to the facts stated above with more ackamarackus.
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Old 3rd April 2023, 06:17 AM   #1439
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Originally Posted by W.D.Clinger View Post
What Mike Helland wrote above implies
a(t) = eH0t
In other words, Mike Helland is saying that, in Helland physics, the size of the universe increases exponentially with time.
I said that expanding model is analogous to my model, in the sense that the same z, lookback time, and demit values are predicted identically by both models.

There is no big bang in a "pure" expanding universe, ΩΛ=1, ΩM=0. Lookback time grows and grows. Not that I'm advocating that. But it is analogous to what I am suggesting for said values.
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Old 3rd April 2023, 06:23 AM   #1440
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Originally Posted by Mike Helland View Post
There is no big bang in a "pure" expanding universe, ΩΛ=1, ΩM=0. Lookback time grows and grows.

That's because, looking backwards in time, the size of the universe shrinks exponentially.

Exponential decay converges toward zero, but never actually reaches zero. Mike Helland didn't know that either.

Which is why we're seeing more of the old ackamarackus.
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