andrew s

While you can't do what you propose light pules transmitted together in the same direction would stay in lock step so in a sense yes you would not see a beams move ahead of each other. Regards Andrew

Photutils a python package has a source extractor but I have not tried it. Regards Andrew

Indeed, by why do think they would change? Non standard SR (i.e. anisotropic c) does not impact this any more than a Lorentz boost (change of inertial frame) where the frequency of the observed light will be red or blue shifted. This doesn't impact the atom In its rest frame. Energy is frame dependant. Being hit by a "stationary" car does not hurt as much as one doing 40mph! In fact anisotropic c is equivalent to a change of reference frame. The underlying Minkowski spacetime is unaffected. Regards Andrew

I see little point in discussing this further with you @Whirlwind. I have provided links to peer review papers on the topic which clearly show that what I have advocated is as empirically justified as conventional SR. Have you bother to look at any of them in detail?. The last one I linked to provides for GPS and Maxwell's equations which covers one of your objections and Robin's. For what it's worth I agree conventional SR provides the simplest equations and is thus to be prefered. Do you object to the Hamiltonian or Lagrangian formulations of classical mechanics because they cannot be empirically differentiated from Newtons theory? They are equivalent as are anisotropic versions of SR equivalent to Einstein's . If that is not enough then nothing I can say will be. Regards Andrew

First rate. Looking forward to the results. Regards Andrew

Do publish it. It would make a nice change from yet another Orion. 😀 Regards Andrew

Somewhat disappointingly, both @robin_astro and @Whirlwind have tried to discredit my position by association with the view of Flat Earth proponents. However, what I am saying is mainstream science see here for a review . I am not sure if I have convinced Robin with my recent posts but if not I propose he write up his position and submit it to a physics journal as if accepted he may well get a Nobel prize. Regards Andrew

Yes, I agree, energy is frame dependant for example the red and blue shift of spectral lines emitted by sources moving away or towards you. Regards Andrew

@Whirlwind you don't have to take my word for it. Just read the papers I linked to. Anisotropic values of c are perfectly valid and compatible with SR and QM. Again don't take my word for it look up the peer reviewed papers in the links I gave. Equally, there is no empirical evidence the speed of light is the same in both directions. It is, despite Robin's claim, a convention. It was a fundamental insight of Einstein's that led him to SR. In your GPS example the clock has changed it's relative motion to you and you need to make SR corrections for that which include the Einstein convention. Regards Andrew In all your examples the equations have the convention built in. Look how Gauss's law changes with anisotropic c in the link. It is these changes that ensure the empirical facts stay the same.

Too much wine during lock down. Regards Andrew

There can be advantages with over sampling with CMOS cameras as it allows you to reduce telegraph noise . See here section 5. Regards Andrew

In the current SI system you are correct. It adopted the Einstein synchronisation convention. However, this was only done after many measurements found it to be invariant and the strong experimental evidence for SR. It is a sensible choice but not the only one that could have been made. The new SI system , unlike the old ones, rests on the validity of both QM and SR if they prove to be wrong things would have to change.. Regards Andrew

As you will see in my last post to Robin you can have different theories that can't be experimentally differentiated and you then have to choose a convention. This is normally done to find one that gives the simplest equations. You can write earth centered equations for planetary motion but they are much more complex that for a sun centered system. Newton's law F = ma does not hold in a rotating frame and you have to add additional forces. I finally found Robin's argument had the isotropy built into the equations he used. Just as you would verify Newton's law in an inertial frame but not in a rotating one (unless you corrected the equations with the pseudo forces needed in a non inertial frame). I would have liked to have found these equations for Robin's experiment but could not find then. However I did find an example from a related area i.e. the Gauss Law. Regards Andrew PS To be explicit you would need a correction to the formula c = fλ with a convention that the one way speeds in the + and - x directions were c/2 and 3c/2 respectively.

@robin_astro ok you are unconvinced. I suspected you might be, but how about this. After some research I have found that you can make SR work with any convention on the one way speed of light from c/2 to infinity provided the average is c for the two way average. See One way speed of light. for example. Since these theories give the same observed outcomes as with the Einstein convention where the speeds are equal and both equal to c they can't be experimentally differentiated. I have not been able to find a formulation of your experiment but I found this paper On the Conventionality of Simultaneity which explains that while the experimental results don't change you need to change the equations. It gives an example of the Gauss law of electromagnetism. So the response to your challenge is that the equations you use i.e. the grating equation and c = fλ have the Einstein simultaneity convention built in i.e. c is isotropic. I am not sure this will convince you but I think this is the best I can do. Regards Andrew

True but you don't measure the speed of light with your apparatus. You deduce it's isotropic but that deduction relies on other assumptions of isotropy. Your null result could be due to a change in c with a corresponding change in frequency or length. We seem to be talking past each other on this. Formally, I think the issue is that you can't measure the one way speed of light if you adopt the Einstein clock synchronisation protocol with assume it isotropic and is built into the current IS system of units. I will post your method on Physics Forums and see if the concur with you. Regards Andrew

In modern physics we don't expect them to be different. However, in aether theory they would be due to motion relative to the aether which is why Michelson and Morrley tried to detect it. It is easy to assume symmetry is never violated but parity P is violated in the weak nuclear interaction and time reversal symmetry in general relativity. If things were perfectly symmetrical we would not be here as all matter and anti matter would have annihilated just leaving radiation and no matter ( it did so in about 1 part in 10^9 if I remember correctly) Regards Andrew

Ditto Regards Andrew

Don't you just live ATI correct! Yes pics please. @Peter Drew should be able to advise you. Regards Andrew

They don't have to be. I have built a number of Newts over the years which had pinpoint stars and track sharp diffraction spikes. Quality optics and precise collimation is mandatory. Regards Andrew

Yes, that's exactly what they are for. Regards Andrew

Yes. Regards Andrew

I can resist anything but temptation! Regards Andrew

Spherical mirrors suffer from spherical aberation which limits their ability to form a sharp image. However, if they have a large enough focal ratio they are very close enough in shape to a parabolic mirror and are diffraction limited. They are much simpler to make than parabolic mirrors. Regards Andrew

Dew might be another possibility. Regards Andrew

The issue is you have you have to assume that space is isotropic so that the frequency is not modified by the direction of propagation. This is esoteric (and unlikely) but so is the issue of the isotropy of the seed if light. If space where like some crystals it would have a different refractive indices depending on both polarisation and and direction. The current SI system assumes both space and the seed of light is isotropic. Regards Andrew