View source for AetherCosPlay Aberration or Starlight

'''Work in progress'''

== Overview ==

On 2026-06-26 on the Earth Awakenings Discord server [[Piezo]] and [[MCToon]] had this conversation about stellar aberration, Bradley's equation, and Airy's failure (transcript: ''Aries failure'').

== Source video ==

Full livestream: [https://www.youtube.com/live/MTqbEjDeCEg Hey Flerfs! Give Evidence] ([https://www.youtube.com/watch?v=MTqbEjDeCEg watch])

{| class="wikitable"
! Section !! Jump to
|-
| Context: Ether theory → stellar aberration pivot || [3:43:03](https://www.youtube.com/live/MTqbEjDeCEg?t=13383)
|-
| Stellar aberration vs. experiments || [3:43:51](https://www.youtube.com/live/MTqbEjDeCEg?t=13431)
|-
| James Bradley's equation || [3:44:24](https://www.youtube.com/live/MTqbEjDeCEg?t=13464)
|-
| Doing the math — Franco, Wikipedia, arcseconds || [3:45:03](https://www.youtube.com/live/MTqbEjDeCEg?t=13503)
|-
| Challenge to reproduce the calculation || [3:47:06](https://www.youtube.com/live/MTqbEjDeCEg?t=13626)
|-
| End of excerpt || [3:47:55](https://www.youtube.com/live/MTqbEjDeCEg?t=13675)
|}

== Discord conversation ==

'''Speakers:''' [[Piezo]] (flat / stationary Earth; aberration is not evidence Earth moves), [[MCToon]] (globe; stellar aberration supports a moving Earth).

'Source:''' [https://www.youtube.com/live/MTqbEjDeCEg Livestream video] ([https://www.youtube.com/watch?v=MTqbEjDeCEg watch]), excerpt [https://www.youtube.com/live/MTqbEjDeCEg?t=13383 3:43:03] – [https://www.youtube.com/live/MTqbEjDeCEg?t=13675 3:47:55]. The transcript spells '''Aries failure''' — almost certainly '''Airy's failure''' (George Airy's 1871 water-filled telescope experiment), not Arecibo.

==== Context: Ether theory → stellar aberration pivot — [https://www.youtube.com/live/MTqbEjDeCEg?t=13383 watch 3:43:03] ====
{| class="wikitable" style="width:100%;"
! style="width:90px;" | Speaker !! Quote
|-
| <span style="color:#2e7d32;font-weight:bold;">Piezo</span> || Yeah. The ve yeah the the a field also known as the vector potential in Maxwell's equations is the ether.
|-
| <span style="color:#1565c0;font-weight:bold;">MCToon</span> || That's it.
|-
| <span style="color:#1565c0;font-weight:bold;">MCToon</span> || And and and how how does so how does that negate how does that negate aberration of starlight and the color shift of starlight?
|-
| <span style="color:#2e7d32;font-weight:bold;">Piezo</span> || So if you want to just start rattling things off one by one, this conversation is going to take forever. But what you asked was right, remember your original question, what are its predictions? And I said, okay, well here is the mathematical description of it that gives all the predictions.
|-
| <span style="color:#2e7d32;font-weight:bold;">Piezo</span> || And now you're like pivoting to let's talk about stellar aberration and all this other stuff.
|-
| <span style="color:#1565c0;font-weight:bold;">MCToon</span> || Yeah, you you it needs to be consistent with those loop.
|-
| <span style="color:#2e7d32;font-weight:bold;">Piezo</span> || It has to be consistent with all of those things though.
|}

==== Stellar aberration vs. experiments — [https://www.youtube.com/live/MTqbEjDeCEg?t=13431 watch 3:43:51] ====
{| class="wikitable" style="width:100%;"
! style="width:90px;" | Speaker !! Quote
|-
| <span style="color:#2e7d32;font-weight:bold;">Piezo</span> || Stellar aberration is not even consistent with experiments.
|-
| <span style="color:#1565c0;font-weight:bold;">MCToon</span> || Yes, it is. Uh not Aries failure. Aries failure was not testing for aberration. It's a stationary geocentric observation. Anyways, a aberration is not a geocentric stationary observation.
|-
| <span style="color:#1565c0;font-weight:bold;">MCToon</span> || Where do you take the measurements from the moving earth as as it confirmed that the earth is moving?
|-
| <span style="color:#2e7d32;font-weight:bold;">Piezo</span> || So, it's geocentric then, right?
|-
| <span style="color:#1565c0;font-weight:bold;">MCToon</span> || No, you're you're assume putting the cart before the horse there, buddy.
|}

==== James Bradley's equation — [https://www.youtube.com/live/MTqbEjDeCEg?t=13464 watch 3:44:24] ====
{| class="wikitable" style="width:100%;"
! style="width:90px;" | Speaker !! Quote
|-
| <span style="color:#2e7d32;font-weight:bold;">Piezo</span> || You're just you're just affirming the consequence. Brad Bradley's equation Bradley's equation does not correctly predict what will happen if you vary one of the two velocities. It only has two input variables. Yeah.
|-
| <span style="color:#2e7d32;font-weight:bold;">Piezo</span> || So if you if you vary one of those variables, then the angle should change and it didn't. That's the important part of invoking when was wait when was when did we vary the rotate the the the linear speed of the Earth around the sun? We didn't we varied the other variable which is the speed of that the light's moving through the telescope.
|-
| <span style="color:#1565c0;font-weight:bold;">MCToon</span> || Ah, yes. But special relativity deals with that just fine. So I don't know what your problem is.
|-
| <span style="color:#2e7d32;font-weight:bold;">Piezo</span> || No, it doesn't.
|}

==== Doing the math — Franco, Wikipedia, arcseconds — [https://www.youtube.com/live/MTqbEjDeCEg?t=13503 watch 3:45:03] ====
{| class="wikitable" style="width:100%;"
! style="width:90px;" | Speaker !! Quote
|-
| <span style="color:#2e7d32;font-weight:bold;">Piezo</span> || Oh, no it doesn't. There you go. You're smarter than 120 years of of people that actually study this. Got it. If you you can you can take either either the publicly available equations straight off of Wikipedia or you can take the equations that we had Franco the CERN physicist write out and do a seven or eight page PowerPoint presentation on for us. Take either of those two equation sets and plug all the variables in and you'll get either 15 or 28 arcsec and his measurement was 20. So all right, I'd love to see that.
|-
| <span style="color:#1565c0;font-weight:bold;">MCToon</span> || Yeah. I mean, you can go on Allan has it on his website or he can send it to you personally if you want it. All right.
|-
| <span style="color:#2e7d32;font-weight:bold;">Piezo</span> || So, you're saying it matches the stationary telescope prediction?
|-
| <span style="color:#1565c0;font-weight:bold;">MCToon</span> || No, I'm saying that the math I'm saying that the I'm saying that the math if you use special relativity and you and you do it with, you know, the index of refraction for water and you plug all the numbers in, depending on which model you use, whether you use the plane wave model or whether you use the like uh photon model, you'll get either 15 arcseconds or 28 arcsec. the plane wave model or the photon model. What are these?
|-
| <span style="color:#2e7d32;font-weight:bold;">Piezo</span> || Well, it's the emission theory and the wave theory of light. There's two different theories for light, right? You can treat it as a wave or a particle.
|-
| <span style="color:#2e7d32;font-weight:bold;">Piezo</span> || So, either depending on which one you use, you'll either get uh 15 arcsec once you put water in the telescope or you'll get 28.
|-
| <span style="color:#2e7d32;font-weight:bold;">Piezo</span> || And Franco did the math for 15. And if you use the other model that's on Wikipedia, you'll get 28, 27, 28. The answer is 20 as to what he measured. It did not change when you put water in it.
|-
| <span style="color:#2e7d32;font-weight:bold;">Piezo</span> || That's the only thing you can't have. It has to change one of the other two. You can't have the angle not change. That's the one thing you can't have. That's what he measured.
|-
| <span style="color:#1565c0;font-weight:bold;">MCToon</span> || I don't think that's the actual answer, but okay. I'll have to look at that. Did we give up on tests of flat Earth?
|}

==== Challenge to reproduce the calculation — [https://www.youtube.com/live/MTqbEjDeCEg?t=13626 watch 3:47:06] ====
{| class="wikitable" style="width:100%;"
! style="width:90px;" | Speaker !! Quote
|-
| <span style="color:#1565c0;font-weight:bold;">MCToon</span> || Yes. Yeah, that that was discarded a while ago. So, I do have uh it's coming up on 2 o'clock here and I got a bunch of super chats to read out. So, I won't uh I won't uh bore the uh Geo server here with that.
|-
| <span style="color:#2e7d32;font-weight:bold;">Piezo</span> || All right. Yeah, if you're going to read those and wrap up your show. But, uh I just wanted to say I don't I mean, nobody gave up on any of those tests. I don't know what you mean. Just in the conversation.
|-
| <span style="color:#1565c0;font-weight:bold;">MCToon</span> || Yeah, the conversation.
|-
| <span style="color:#2e7d32;font-weight:bold;">Piezo</span> || You should make a follow-up video, mcune, where you where you do the math force failure. You can get the equations like they're on Wikipedia or where we can give you the Franco's presentation if you want both models and you can just plug the numbers in and see what it spits out. It's not going to spit out 20. I can tell you that.
|-
| <span style="color:#1565c0;font-weight:bold;">MCToon</span> || You should do a follow-up for your viewers. Sure.
|-
| <span style="color:#2e7d32;font-weight:bold;">Piezo</span> || Did you decide on a test? Did you decide?
|-
| <span style="color:#2e7d32;font-weight:bold;">Piezo</span> || So everybody can see so everybody can see what the velocity of light is in the water frame or in the sun frame, right? you get.
|-
| <span style="color:#1565c0;font-weight:bold;">MCToon</span> || So, yeah, Brenda, no test was agreed on.
|}

== TruthNerds response ==

In the comments section of that video, '''TruthNerds''' wrote:

<blockquote>
A flat Earther found a formula which he doesn't understand and put some numbers in it. When has that ever happened before! (Warning, long post … see Brandolini's Law)

Anyway, Geo claims that Alan calculated the expected stellar aberration in Airy's failure experiment and that it doesn't match SR. By plugging in different light speeds, apparently. 😂

Ok, insider joke? I'll elaborate.

Let's first look at what Geo means by Bradley's formula. The classical formula is derived assuming that light propagates as a wave with a given speed in a stationary medium, aka aether, and the application of Newtonian mechanics.

It is θ - arctan(sin θ / (v/c + cos θ)) where θ is the angle of movement relative to the viewing direction, v is speed and c is the speed of light.

Then there's the relativistic formula, which is θ - 2 arctan(sqrt((1-v/c)/(1+v/c)) * tan(θ/2)). The relativistic formula reduces to the classical formula for v << c. Furthermore, for θ = 90° and v<<c, both reduce to v/c (in radians) as an approximation.

Ok, first, let's do some calculations, plain 90° aberration with Earth's average orbital speed gives about 0.0996 mrad (about 20.5 arcseconds) both for the classical and for the relativistic formula. It really makes no difference at those speeds!

Now, what did Alan presumably do to model Airy's experiment? Changing θ makes no sense, we want to keep that constant for comparability. Changing v makes no sense because Earth's speed wouldn't change. So he must've modified c. And that is hilarious!

Why? Well, for how Bradley's formula was derived, it would make sense because it is originally based on the assumption of a wave propagating through the aether. Slower wave propagation would thus affect the aberration angle.

But it doesn't make any sense to vary c in the relativistic formula! The relativistic formula is not derived from any assumption about a wave propagating through a fixed medium, it is based on the Lorentz transformation and the postulates of Special Relativity:

# The laws of physics are the same in all inertial frames.
# The speed of light in a vacuum (denoted c) is the same for all observers.

The speed of light to plug into the relativistic formula is always that same c, it has nothing to do with wave propagation in a medium. The formula follows from a coordinate transform in 4D spacetime. I.e. it is derived geometrically. It doesn't care about whether the light goes through a vacuum, air, water, glass or what have you.

Alan is once again debunking himself: If (classical) aether theory were correct, then Airy's experiment should have detected a change in aberration angle consistent with Bradley's formula (using different c).

Airy did not detect such a change, which is entirely consistent with SR. Alan therefore must straw man SR and misapply the relativistic formula in order to try and discredit it.
</blockquote>

=== PS ===

<blockquote>
The speed of light is actually the same in all media if you take the front velocity of a light pulse. That might also be called the speed of causality. What changes in water is the phase velocity. While this is very important for some optical effects, namely refraction, it is irrelevant for the derivation of the relativistic aberration formula.
</blockquote>

=== PPS ===

<blockquote>
Why do we still use the classical formula? It is simpler and a good approximation for non-relativistic speeds. However, we now know to also only use constant c in it. Then the formula's original derivation becomes invalid, but it remains valid as a numerical approximation. (It can be independently derived as an approximation of the SR formula.)
</blockquote>

[[Category:AetherCosPlay]]
[[Category:Stellar aberration]]