pervect said:
Emission theory is already dead except in the lunatic fringe.
Not saying that I'm putting my money on Emitter theory rather than on Relativity but;
All theories are just abstract models. This is given by the way we handle all information in our mind only semantically. There's a good account of this in "
https://www.amazon.com/gp/product/0316328197/?tag=pfamazon01-20" by John Gribbin.
When people forget this, they tend to start treating (somewhat unconsciously) abstract models as something more than a model; as reality. Even though such models are always, by definition, circular ones (like the way we visualize atoms as if they looked like some everyday objects, that are made of atoms).
Such a thinking tends to make it harder to recognize that a wide number of different models can actually also explain all the phenomena we have observed, and thus should not be rejected as an invalid model. Rejecting them goes counter to the scientific paradigm "invented" by Newton. I think he recognized all the scientific ideas we have ever had are just abstract models, as indicated by observations.
That being said, I've never quite understood what exactly is being demonstrated about emitter theory by that Alväger's test. I could be horribly wrong, but I assume it has to do with someone pushing some artificial mental model beyond its limits. And I think the model in question, is the idea that in emitter theory "light moves like bullets", and then it is thought this means that denser matter slows down light as if a bullet was shot into a jelly. I know some people tend to get that idea in their head, because they act so amazed when they are being told that when light enters a medium, it slows down, but when the light exits the air, it speeds up again. Of course, the mental model has just shown its limit.
What emitter theory says, quite simply, is that matter, i.e. atoms, emit light at the speed C relative to themselves. We pretty much
know that the speed of light slows down in denser "medium", because every atom inside the medium absorb the light, and with a small delay pass it on. It is these delays that slow down the propagation speed. The more denser the medium, the more atoms to hop through, and the less speed we measure. But the light itself never changes its speed per se. That idea is in agreement with experiment AND Standard Model, as far as I know. If emitter theory was claiming anything different, it would be in trouble.
So my mental model of emitter theory is just like "information packets" being tossed between atoms, hopping from atom to atom. Not light passing through air "like a bullet" from a moving flashlight. Every atom that relays the information, must also regulate its speed.
And that is why I don't understand, how are gamma rays in that experiment suddenly free of the Standard Model? How could a gamma ray pass through some beryllium, mylar window and some 60 meters of air, without ever touching a single atom? Has someone made a meaningful comment about this?
About the binary stars, I thought it was just a commonly accepted fact that the argument is invalid. Because we know now that the vacuum of space is not actually a perfect vacuum,
especially nearby binary star systems. We should expect all kinds of stuff to orbit the whole system. In other words, the atoms of all that crap should still be absorbing and re-emitting light, just like in Standard Model.
Also, as far as I know, the original argument was that it would become impossible to see visual binaries because the image would get blurred into one. We know now that only a small portion of binaries are visual binaries, even through a telescope.
http://www.astronomical.org/astbook/binary.html
"Only a small portion of binary stars are visual binaries. In order to see a visual binary, the stars must be separated by fairly wide distances, and the orbital periods are usually very long."
And there are estimates that actually, half of all the stars in the sky are members of binaries;
http://astrosun2.astro.cornell.edu/academics/courses//astro201/binstar.htm
"Five to ten percent of the stars visible to us are visual binary stars. Careful spectroscopic studies of nearby solar-type stars show that about two thirds of them have stellar companions. We estimate that roughly half of all stars in the sky are indeed members of binaries."
--
Hmmm, while I already got a bit philosophical, I would like to carry on with few words about mental models. (sorry :)
Think about the idea of ether. As it became apparent that light was a wave, people applied a mental model of waves on ponds and such, and so thought there must be some sort of matter on which these waves propagate, since waves always propagate as a motion of matter.
Well, we know electromagnetism is what basically makes up matter. Why should anyone expect, that something which makes matter, is also moving "as a motion of matter"? Even if M&M had found that aether exists, it wouldn't mean it is
anything like matter in reality.
Or think about an atom. What does an atom look like? Or what does an electron look like? Or quark? What color and what shape are they, or do they look "foggy" or something like that?
How could you ever see what an electron looks like, since it is the very function of the electron to give off a photon. What things look like is wholly dependent on the shape that the sea of photons reveal, but when you tried to see what an electron looks like, all you can do, by definition, is catch a photon it emits. It "looks" like the photon that it gives off. It "looks" like a quantum step of an atom on the measuring instrument.
Or think about quark. It doesn't have such a function as give off a photon. By definition, it doesn't "look" like anything, no matter how close you look. The problem is not that it's "so small". Even if it was two meters wide and three meters high, it still wouldn't "look" like anything, since it doesn't have such a function as to give off a photon at all. (That means it doesn't reflect photons either, since reflection is about absorbing and emitting information)
You can't even "feel" what this quark looks like, since it doesn't have the function that our sense of touch is based on; electromagnetism.
It is difficult to imagine in your mind what is some entity like that by definition does not have any "look". Any shape or color (not even white or black), nor does it collide with your hands like matter. It is difficult, because you classify information by relating things to other things, and in this case there's really nothing else "like" electron, but the electron itself. Or quark. Or photon. (What does a photon look like? Etc...)
But still, people get hung up to all kinds of circular mental models that are out there, as if they were describing any sort of reality. Like you often hear how electron exists on one orbit around an atom, and then it "just disappears from that orbit and re-appears on another orbit, without moving in between". And this is somehow "amazing". Well, it is only amazing to anyone who forgot that the planetary model was just a model. If you are measuring something like frequency, it is not amazing at all to notice that one wave comes in the length X, and the immediate second wave comes in some different length Y.
In fact, when I said "electron gives off a photon", that is also a mental model. We could probably build a perfectly good model where the atom itself gives off a photon (or causes a ripple in space, or whatever floats your boat), thus causing the energy level of itself to drop, which we measure the way we measure it. That electron seems to be like a rainbow or a shadow anyway, caused by the atom, and we just interpetate the measurement as if there was a material particle there (or whatever).
It should also be recognized with all these scientific models, that success breeds success. That means, that when some model is thought to be more elegant than the others due to the experimental data at that point, it tends to shove all the alternative models out of its way, in the sense that they don't get much attention anymore. Had the emitter theory been pushed forwards after M&M test, and become accepted as the "best model" at that time (entirely possible, since the only argument was AFAIK the binary star argument), then advocates of relativity theory would be hit in the head with their "inability to explain inertia", and their "crackpot idea" about relativity of time.
That kind of stuff is always so annoying to me. That's why in my mind no model is ever truly "dead" in the sense that it wouldn't deserve any attention. In my interpetation, the scientific paradigm says we should keep pushing all the models, and inventing new version "just for the heck of it", if we really want to close in on the "truth" :)
So, while I find the mountain of evidence towards relativity very interesting, I think the little problems and the speculation on them is even more interesting :)
I have sympathy for all this kind of stuff:
http://www.wbabin.net/sokolov/sokolov4.pdf
-Anssi