I understand.Your theory is based on photon movements.
Actually I believe in Dark matter theory, but it doesn't explain this phenomenon fully because there are still some differences between star velocities. And if we're talking about billions of years, even these difference will destroy any star formation bigger than few thousand light years. So these theories do not contradict each other
but the theory about photon and darkmatter or fusion experiments are not defined.Your theory can be right thing.
there is darkmatter theory that explains galaxy arm moving.it says gravity of darkmatter holds galaxy stable.
Yup. If they were actual star formations, they would stretch out over time, and after billions of years they would become rings, which doesn't happen
you mean...galaxy arms seem spinning,but actually they are just glowing because there are lots of stars?
aurimukstis1, I would agree with the statement "that's only one theory, there are more ways in which galactic arms could form". But that theory (by the way its name is "density wave theory") makes a lot of sense for a large portion of scientific community. If you don'understand how does that work, here you go https://en.wikipedia.org/wiki/Density_wave_theory
that is not how this works...
next we need one withmultiple arms
i do think that some galaxy arms do spin