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Old 30th January 2021, 05:38 PM   #2041
Steve
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Originally Posted by theprestige View Post
Show us the math.
Now that is really where the whole idea falls apart.
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Old 30th January 2021, 05:49 PM   #2042
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Originally Posted by Steve View Post
Now that is really where the whole idea falls apart.
Basic model:

v_light=c

Expanding model:

v_light=c
v_everythingAwayFromUs = HD

My model:

v_light=c-HD

The following shows what the math says a photon traveling in these models would be in spacetime:



The blue line is the basic model, the white line is the expanding model, and the green line is v=c-HD.

The white line is hidden behind the green line.

The green line is taken as the photon's path in an otherwise flat spacetime.

When calculating the path of light, you solve the geodesic equation for -HD/t instead of 0.
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Old 30th January 2021, 05:55 PM   #2043
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Originally Posted by Mike Helland View Post
Basic model:

v_light=c

Expanding model:

v_light=c
v_everythingAwayFromUs = HD

My model:

v_light=c-HD

The following shows what the math says a photon traveling in these models would be in spacetime:

https://mikehelland.github.io/hubble...ime_delays.png

The blue line is the basic model, the white line is the expanding model, and the green line is v=c-HD.

The white line is hidden behind the green line.

The green line is taken as the photon's path in an otherwise flat spacetime.

When calculating the path of light, you solve the geodesic equation for -HD/t instead of 0.
Don't show us what you think the math says. Show us the math.

Maxwell's equations aren't computer code. They're math. General relativity isn't computer code. It's math. Liebniz didn't write computer programs. He did differential calculus. Can you do differential calculus? Forget your computer code. Show us your math.
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Old 30th January 2021, 06:00 PM   #2044
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Originally Posted by theprestige View Post
Don't show us what you think the math says. Show us the math.

Maxwell's equations aren't computer code. They're math. General relativity isn't computer code. It's math. Liebniz didn't write computer programs. He did differential calculus. Can you do differential calculus? Forget your computer code. Show us your math.
The math I'm using is v=c-HD

What do you want me to show with it?
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Old 30th January 2021, 06:00 PM   #2045
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Originally Posted by theprestige View Post
How does any particle travel through a vacuum? Momentum and inertia, yes?
I suppose understanding the mechanics of light is on topic.

Light is a wave, a wave can't 'shoot the gap' when it encounters empty space.

When light passes through matter how does it return to speed when it reenters a vacuum?
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Old 30th January 2021, 06:05 PM   #2046
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Originally Posted by Mike Helland View Post
The math I'm using is v=c-HD

What do you want me to show with it?
Show us that this is the geodesic to your spacetime metric. The word "geodesic" means something. You can't just throw it around without justifying its use.
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Old 30th January 2021, 06:11 PM   #2047
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Originally Posted by Mike Helland View Post
The math I'm using is v=c-HD

What do you want me to show with it?
Show us how you modify Maxwell’s equations to be compatible with more than one speed of light at a location.

Last edited by hecd2; 30th January 2021 at 06:18 PM.
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Old 30th January 2021, 06:22 PM   #2048
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Originally Posted by Ziggurat View Post
Show us that this is the geodesic to your spacetime metric. The word "geodesic" means something. You can't just throw it around without justifying its use.
Fair enough.

To calculate the path of a photon, you set its velocity vector to zero, right?
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Old 30th January 2021, 06:30 PM   #2049
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Quote:
Originally Posted by*Ziggurat*

Yeah, no. It doesn’t work like that.

There are only a few ways light can red shift without scattering, and we understand those pretty well. And scattering is not responsible for cosmological red shifts, because it would blur images of distant objects. But they are not blurred, so it isn’t scattering
The light doesn't scatter because it is not made of particles
Anyhoo,

In the post you were responding to, I was referring to the light waves expanding as they travel, as they stretch wider, this would shorten the overall length of the photon. Would this squeeze change colors?

Last edited by Nakani; 30th January 2021 at 06:31 PM.
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Old 30th January 2021, 06:34 PM   #2050
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Originally Posted by Mike Helland View Post
Fair enough.

To calculate the path of a photon, you set its velocity vector to zero, right?
Yeah... no.

You arenít going to be able to do this. You donít have the math skills. And in this case, thatís really not an insult. The math required is far beyond just algebra.
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Old 30th January 2021, 06:35 PM   #2051
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Originally Posted by Nakani View Post
The light doesn't scatter because it is not made of particles
Anyhoo,

In the post you were responding to, I was referring to the light waves expanding as they travel, as they stretch wider, this would shorten the overall length of the photon. Would this squeeze change colors?
No. In a freely propagating expanding light wave the intensity falls with distance, the frequency (colour) is unaffected.
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Old 30th January 2021, 06:39 PM   #2052
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Originally Posted by Nakani View Post
The light doesn't scatter because it is not made of particles
Anyhoo,

In the post you were responding to, I was referring to the light waves expanding as they travel, as they stretch wider, this would shorten the overall length of the photon. Would this squeeze change colors?
Stretching sideways does not shorten the length, and it does not change the color. The intensity of the field reduces. Energy density is proportional to the square of the field strength, and you are spreading that energy out over a larger area.
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Old 30th January 2021, 06:46 PM   #2053
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Originally Posted by Ziggurat View Post
Yeah... no.

You arenít going to be able to do this. You donít have the math skills. And in this case, thatís really not an insult. The math required is far beyond just algebra.
No shame in not having the math skills. Way above my pay grade. But even I recognize that if you don't have the math you don't have a viable hypothesis, never mind a theory.
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Old 30th January 2021, 06:52 PM   #2054
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Originally Posted by Nakani View Post
I suppose understanding the mechanics of light is on topic.

Light is a wave,
No it is not. Light has both particle-like and wave-like properties. It is not exclusively or definitively either of those things.

Quote:
a wave can't 'shoot the gap' when it encounters empty space.
You know this about EM waves how?

Quote:
When light passes through matter how does it return to speed when it reenters a vacuum?
I'm not sure you understand what "return to speed" means for massless particles.
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Old 30th January 2021, 06:53 PM   #2055
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Originally Posted by Mike Helland View Post
The math I'm using is v=c-HD
That is your claim.

Quote:
What do you want me to show with it?
I want to you to show the math you worked to derive v=c-HD.
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Old 30th January 2021, 06:55 PM   #2056
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Originally Posted by Ziggurat View Post
Yeah... no.

You arenít going to be able to do this. You donít have the math skills. And in this case, thatís really not an insult. The math required is far beyond just algebra.
Over the years, I've come to the conclusion that mathematics doesn't really begin until somewhere around the differential calculus. Everything before that is just noodling around with basic axioms. Algebra is just preparatory concepts for those who aim to master the calculus and become apprentice mathematicians.
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Old 30th January 2021, 06:58 PM   #2057
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Originally Posted by Ziggurat View Post
Yeah... no.
Then what is this about:

https://youtu.be/-UPSiKugRW0?t=880

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Old 30th January 2021, 07:01 PM   #2058
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Originally Posted by theprestige View Post
I want to you to show the math you worked to derive v=c-HD.

If the photon is traveling at c, and its target gains velocity away from it, that's like losing velocity toward it.

Hubble's law is v=HD. That's the speed things move away.

If I used that as the speed the photon loses, it predicts the same time delays as expanding space.

It wasn't so much derived but hypothesized.
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Old 30th January 2021, 07:11 PM   #2059
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Originally Posted by Mike Helland View Post
If the photon is traveling at c, and its target gains velocity away from it, that's like losing velocity toward it.

Hubble's law is v=HD. That's the speed things move away.

If I used that as the speed the photon loses, it predicts the same time delays as expanding space.

It wasn't so much derived but hypothesized.
That's not math, that's English. Where is your math?
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Old 30th January 2021, 07:17 PM   #2060
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Originally Posted by Mike Helland View Post
Then what is this about:
The length is zero, not the vector. And that means it travels at c. But thatís still not enough to specify a geodesic. And it doesnít explain YOUR trajectory, which is certainly not a null vector under relativity.
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Old 30th January 2021, 07:21 PM   #2061
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Originally Posted by Ziggurat View Post
The length is zero, not the vector. And that means it travels at c.
So if the length was -HD, what would it travel it?

*edit* shoudl be -HDt

Last edited by Mike Helland; 30th January 2021 at 07:23 PM.
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Old 30th January 2021, 07:49 PM   #2062
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Originally Posted by Mike Helland View Post
So if the length was -HD, what would it travel it?

*edit* shoudl be -HDt
You tell us. With your math.
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Old 30th January 2021, 08:27 PM   #2063
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Originally Posted by theprestige View Post
No it is not. Light has both particle-like and wave-like properties. It is not exclusively or definitively either of those things.
Does that mean, when we need it to be a particle it is? With our current technology can we even examine the whole photon, or do we just get a peak at a 'particle'?

Quote:
You know this about EM waves how?
In my coffee there are little waves, when my cup is empty the waves are gone.

Quote:
I'm not sure you understand what "return to speed" means for massless particles.
If light slows down as it passes through a medium, how does it return to the speed considered the constant?
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Old 30th January 2021, 08:32 PM   #2064
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Originally Posted by Nakani View Post
If light slows down as it passes through a medium, how does it return to the speed considered the constant?
At the quantum level, the medium is just a bunch of atoms or molecules with vacuum in between

The photon is absorbed and remitted by these atoms. It loses a little bit of time when it's in an atom. These little bits add up to the speed deficit.

When it leaves the atom, it goes back to a vacuum, and thus back at c.

The photon is never not traveling at c, at the quantum level, even "in" a medium.
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Old 30th January 2021, 08:46 PM   #2065
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Originally Posted by Ziggurat View Post
Stretching sideways does not shorten the length, and it does not change the color.
Are you sure? My research indicates, stretching something makes it skinnier. It seems, this skinnier photon would have a different frequency than it started with.

Quote:
The intensity of the field reduces. Energy density is proportional to the square of the field strength, and you are spreading that energy out over a larger area.
Is this the only thing that happens?
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Old 30th January 2021, 08:54 PM   #2066
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Originally Posted by Mike Helland View Post
At the quantum level, the medium is just a bunch of atoms or molecules with vacuum in between

The photon is absorbed and remitted by these atoms. It loses a little bit of time when it's in an atom. These little bits add up to the speed deficit.

When it leaves the atom, it goes back to a vacuum, and thus back at c.

The photon is never not traveling at c, at the quantum level, even "in" a medium.
Ok, I see the logic. I'm not a fan of the absorbed and remitted part though.

Could you point me to evidence of this?
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Old 30th January 2021, 09:27 PM   #2067
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Originally Posted by Nakani View Post
Does that mean, when we need it to be a particle it is?
No. It means that photons have particle-like properties and wave-like properties, all day, every day.

Quote:
With our current technology can we even examine the whole photon,
Yes

Quote:
or do we just get a peak at a 'particle'?
No.

Quote:
In my coffee there are little waves, when my cup is empty the waves are gone.
In what way are waves in your coffee analogous to waves in an electromagnetic field? What can we learn about the nature of electromagnetism, by analogy to your coffee?

Quote:
If light slows down as it passes through a medium, how does it return to the speed considered the constant?
That speed is the natural resting state of massless particles, absent some external effect like a medium.

You need to stop thinking about photons in terms of the kinds of massy macro-scale objects you're familiar with. You need to start thinking about them in terms of massless particles, their properties and implications.
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Old 30th January 2021, 09:31 PM   #2068
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Originally Posted by Nakani View Post
Are you sure?
Yes.

Quote:
My research indicates, stretching something makes it skinnier.
Solids cannot typically get more diffuse, and so to conserve both mass and density, they must shrink in one direction if stretched in another.

But photons are not solid. They must conserve energy, but they do not need to conserve energy density. Gasses are similar in that respect: you can expand them in multiple directions simultaneously, since density is not fixed, without violating mass conservation.

Quote:
It seems, this skinnier photon would have a different frequency than it started with.
Definitely not.

Quote:
Is this the only thing that happens?
Yes.
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Old 30th January 2021, 10:01 PM   #2069
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Originally Posted by Nakani View Post
Ok, I see the logic. I'm not a fan of the absorbed and remitted part though.

Could you point me to evidence of this?
Well, stand in the sun. Your skin absorbs light and heats up. This is also fun to play with:

https://phet.colorado.edu/sims/html/...-light_en.html

As far as the quantum level, that's quantum electrodynamics.

A photon goes from one place and time to another place and time.
An electron goes from one place and time to another place and time.
An electron emits or absorbs a photon at a certain place and time.

https://en.wikipedia.org/wiki/Quantu...lectrodynamics
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Old 30th January 2021, 10:41 PM   #2070
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Originally Posted by theprestige View Post
That's not math, that's English. Where is your math?
There's this paper here, where they're basically doing the same thing for a different hypothesis.

https://arxiv.org/abs/gr-qc/9701009

They set the right hand side of the geodesic equation to something non zero.
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Old 31st January 2021, 12:14 AM   #2071
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Originally Posted by theprestige View Post
You tell us. With your math.
Originally Posted by Mike Helland View Post
There's this paper here, where they're basically doing the same thing for a different hypothesis.

https://arxiv.org/abs/gr-qc/9701009

They set the right hand side of the geodesic equation to something non zero.
Where is your math?

I stand by my previous post. Your "paper" was submitted and returned. The reviews state that there are "misunderstood concepts" and that the article "is based on incorrect physics". Why haven't you taken the time to understand the correct concepts and/or understand physics? I know I don't know everything, but at least I know when people tell me I'm making mistakes, when to study more, and I know when to take advice from people who have more experience than me.

Edit: let me correct myself. I meant to say that I think my original post is partially correct. To me, Mike Helland comes across as "I'm right because Science can't explain everything".

Last edited by Little 10 Toes; 31st January 2021 at 12:54 AM.
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Old 31st January 2021, 06:22 AM   #2072
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Originally Posted by Mike Helland View Post
There's this paper here, where they're basically doing the same thing for a different hypothesis.

https://arxiv.org/abs/gr-qc/9701009

They set the right hand side of the geodesic equation to something non zero.
They actually solved the equation. You havenít. Saying light can go slower than c is different than saying it goes at this particular velocity.
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Old 31st January 2021, 10:15 AM   #2073
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Originally Posted by Mike Helland View Post
There's this paper here, where they're basically doing the same thing for a different hypothesis.

https://arxiv.org/abs/gr-qc/9701009

They set the right hand side of the geodesic equation to something non zero.

I believe you have misunderstood what they did. They describe their equation (2) as a "generalization of the geodesic equation"; please note the word I highlighted. They obtain that generalization "in the geometrical optics limit", which is an approximation (as they explicitly acknowledge just before equation (17)). From my cursory reading of the paper, noting the discussion following equation (48), they found it convenient to apply that approximation to the geodesic equation rather than deferring its application to Maxwell's equations.

It seems to me that their abstract is somewhat misleading when it says "Photons are found to have an effective mass in an external gravitational field and their velocity in an inertial frame is, in general, less than c." On my reading, they are talking about coordinate velocity and the apparent slowing of light in strong gravitational fields such as near a black hole, which is bog-standard general relativity.

The journal version of that preprint appears to be

Subhaendra Mohanty, A.R. Prasanna. Photon propagation in Einstein and higher derivative gravity. Nuclear Physics B, Volume 526, Issues 1-3, 24 August 1998, Pages 501-508. https://www.sciencedirect.com/scienc...50321398002752
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Old 31st January 2021, 10:30 AM   #2074
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Originally Posted by Ziggurat View Post
They actually solved the equation. You havenít. Saying light can go slower than c is different than saying it goes at this particular velocity.
Still, you're acting as if there's no way in the world it can be done.

Move Hubble's law from the scale factor to the a limit of a photon's world line.

My guess is, if you genuinely know GR well, you probably even know the right way to do it.
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Old 31st January 2021, 11:52 AM   #2075
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Originally Posted by W.D.Clinger View Post
I believe you have misunderstood what they did. They describe their equation (2) as a "generalization of the geodesic equation"; please note the word I highlighted. They obtain that generalization "in the geometrical optics limit", which is an approximation (as they explicitly acknowledge just before equation (17)). From my cursory reading of the paper, noting the discussion following equation (48), they found it convenient to apply that approximation to the geodesic equation rather than deferring its application to Maxwell's equations.

It seems to me that their abstract is somewhat misleading when it says "Photons are found to have an effective mass in an external gravitational field and their velocity in an inertial frame is, in general, less than c." On my reading, they are talking about coordinate velocity and the apparent slowing of light in strong gravitational fields such as near a black hole, which is bog-standard general relativity.

The journal version of that preprint appears to be

Subhaendra Mohanty, A.R. Prasanna. Photon propagation in Einstein and higher derivative gravity. Nuclear Physics B, Volume 526, Issues 1-3, 24 August 1998, Pages 501-508. https://www.sciencedirect.com/scienc...50321398002752
I think they are talking about the gravitational spin-Hall effect arising from spin coupling with space time curvature. Top review article here, Oancea et al, An overview of the gravitational spin Hall effect; which is a second order effect that relies on the fact that the propagation is in a strongly curved spacetime.

It has nothing to do with Mikeís idea, so I have no idea why he posted the link as it doesnít help him at all.
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Old 31st January 2021, 11:56 AM   #2076
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Originally Posted by Mike Helland View Post
Still, you're acting as if there's no way in the world it can be done.

Move Hubble's law from the scale factor to the a limit of a photon's world line.

My guess is, if you genuinely know GR well, you probably even know the right way to do it.
Nope I don’t think it can be done within the postulates of GR just as I don’t think you can modify Maxwell’s equations in a way that allows more than one speed of light at a location and is backwards compatible with the rest of electromagnetism’s correct predictions.
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Old 31st January 2021, 12:13 PM   #2077
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Originally Posted by hecd2 View Post
Nope I donít think it can be done within the postulates of GR just as I donít think you can modify Maxwellís equations in a way that allows more than one speed of light at a location and is backwards compatible with the rest of electromagnetismís correct predictions.
This is why the expanding universe was such a great idea.

"Hey, so we can see farther than we ever have, and we found this thing... these redshifts."

"Oh boy. Does that mean we have to change a lot of theories?"

"No! We just expand space itself, and all the theories follow!"

In 1970, it was clearly the best, most elegant solution.

50 years later and the original expanding universe is somewhere in there, underneath all the tape and glue.

Personally, I think we can change the geometry of spacetime using Hubble's law a different way than expanding space but with similar results for the world line of a photon.

I think that's probably done in the geodesic equation, but I think we all know that's just my kamikaze approach to science.

The best part about crashing hypotheses into the ground is no one gets hurt.
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Old 31st January 2021, 12:46 PM   #2078
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Originally Posted by Mike Helland View Post
There's this paper here, where they're basically doing the same thing for a different hypothesis.

https://arxiv.org/abs/gr-qc/9701009

They set the right hand side of the geodesic equation to something non zero.
That's their math, not your math. Where's your math? Where's your paper, or blog article, or git repo, or forum post where you do basically the same thing they're doing, but for your hypothesis?

Even if all you did was forklift their formulas directly into your work, did the sums, and discovered that those formulas also support your hypothesis, you should still have a record somewhere of having done exactly that. Where's your record? Where's your math?
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Old 31st January 2021, 01:02 PM   #2079
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Originally Posted by Mike Helland View Post
Personally, I think we can change the geometry of spacetime using Hubble's law a different way than expanding space but with similar results for the world line of a photon.
Show us how that can be done. Until you do, your claims carry no more weight than if I were to claim that the fairies at the bottom of the garden are responsible for it all.
Quote:
I think that's probably done in the geodesic equation, but I think we all know that's just my kamikaze approach to science.
Show us how, and don't forget the modifications to the Maxwell equations while you're about it.


What do I think? I think you;'re throwing around words like spacetime and geodesic and geodesic equation that you have read somewhere without having the faintest idea what they mean.
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Old 31st January 2021, 01:14 PM   #2080
Mike Helland
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Originally Posted by hecd2 View Post
Show us how that can be done. Until you do, your claims carry no more weight than if I were to claim that the fairies at the bottom of the garden are responsible for it all.
Show us how, and don't forget the modifications to the Maxwell equations while you're about it.


What do I think? I think you;'re throwing around words like spacetime and geodesic and geodesic equation that you have read somewhere without having the faintest idea what they mean.
I understand why you're focused on Maxwell's equations, but I'm telling you, a bigger problem is inertia itself. Does it hold to infinity? If redshifts are taken as evidence that they do not, then inertia itself must be tweaked. An object in motion at velocity v remains in motion at velocity v'=v-HD.

Since geodesics are paths of "pure motion", ie, just inertia, modifying inertia means modifying the geodesic. (*edit* or in my case adding a new class of geodesics.)

Beyond that, yeah, I'm just guessing.

Last edited by Mike Helland; 31st January 2021 at 01:17 PM.
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