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/sci/ - Science & Math


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File: 1.46 MB, 1508x940, textbook_doppler.png [View same] [iqdb] [saucenao] [google]
14767114 No.14767114 [Reply] [Original]

Continuing this discussion here because the other thread is being derailed.

Picrel is how textbooks pull the wool over your eyes using approximations. These approximations are fine for speeds much smaller than c, but when we are dealing with experiments that require precision, such as the Michelson-Morley experiment, the exact equation for Doppler shift at an arbitrary angle is required.

For the uninitiated, the full equation is derived in section 3.5 of this paper: https://osf.io/vkb2z

You can see from figure 12 of the paper (and from common sense) that there is clearly wavelength contraction at 90 degrees--something that the approximation doesn't predict at all, because it's not the correct formula. Physicists would have us believe that there is no classical wavelength contraction at 90 degrees whatsoever.

When you use the correct formula for Doppler shift, it turns out that the Lorentz contraction from relativity is really just the wavelength factor of contraction at 90 degrees. This is derived simply in section 4.3.

Please utilize the available space below to cope and seethe.

>> No.14767805

>>14767114
It's really funny to me that most physicists are doing the physics equivalent of trisection. Approximations aren't meant to be used to prove truths in idealized conditions.

>> No.14767834

>>14767114
Isn't this simply the normal Doppler effect? Not the relativistic one.

>> No.14767839

>>14767834
nathan hasn't figured it out yet--he's busy harassing actual physicists now.

>> No.14767849

>>14767839
I didn't see the original thread. Did he delete it?

>> No.14767870

>>14767849
>>14764354
just scroll to the images.

>> No.14767966

>>14767834
Yes. That's the point. There is no relativistic Doppler effect. It's all classical. Physicists just aren't using the correct equation for classical Doppler shift. They use an approximation (as shown in the picture).

>> No.14767979
File: 251 KB, 500x375, 1591927216543.png [View same] [iqdb] [saucenao] [google]
14767979

>the Lorentz contraction from relativity is really just the wavelength factor of contraction at 90 degrees

>> No.14768176

>>14767966
>There is no relativistic Doppler effect. It's all classical.
How?

>> No.14768182
File: 68 KB, 903x508, read.jpg [View same] [iqdb] [saucenao] [google]
14768182

>>14768176
>How?
https://osf.io/vkb2z

>> No.14768194

>>14768182
The whole issue of the relativistic doppler equation and classical one is not one that you can really prove with recourse only to the issue of doppler equations and the MM Experiment. We accept that relativity is correct because it kind of has to be and there's a lot of evidence for it. How else are we to explain all the galaxy gravitational lensing going on in James Webb images etc. Because we accept relativity is correct, the equation for the relativistic doppler shift is the way it is. No other reason.

>> No.14768259

>>14768194
>How else are we to explain all the galaxy gravitational lensing going on in James Webb images etc.
Alternative explanations have been proposed. I believe Halton Arp had a pretty significant observational list of alleged Einstein Crosses that were inconsistent with relativity.

>> No.14768505
File: 116 KB, 458x878, einstein_cross.png [View same] [iqdb] [saucenao] [google]
14768505

>>14768259

>> No.14768508

>>14768505
Yep. It's true, but nobody wants to hear it. Story of astrophysics in a nutshell.

>> No.14769861

bump

>> No.14770684

>>14767114
I don't think you know what 90 degrees is. While doppler shift has a bunch of bs around it, perpendicular shift is not the hill to die on.
This is easily verified inside a car talking to another person as both are sources and receivers and are both moving.

>> No.14770711

>>14768194
>and there's a lot of evidence for it
and that amount is meaningless. The Law is universal and as such it requires universal proof.

>> No.14770767

>>14767114
When will zoomer faggots stop making white papers from literal /sci/ posters ideas trying to get fame and credit?
Fuck you faggot

>> No.14771030

>>14770684
My theory predicts that the wavelength of sound would be contracted by 0.3% for two people sitting next to each other in a car traveling 60 mph--and that assumes they are in a convertible shouting at each other. That's probably not that easy to detect without instruments. Also, as I discuss in my paper, the frequency would be unaffected, so there wouldn't be any pitch difference to detect; only a difference in arrival times.

>> No.14771037

>>14770684
>>14771030
So if two people are sitting three feet apart in their convertible at 60 mph, they would have to detect whether there was an extra 8.4 microsecond difference in the one-way travel time. That would probably be hard to pick up on.