I think the cosmological redshift, called the "Hubble" redshift which Edwin Hubble discovered and photographed, is caused by quantum decay in light and other electric field) waves, i.e. photoelectric radiation. When emitted, light from a particular elements electronic transitions are at the...
No universal expansion, just fading energy
Marcus
I think the redshift comes from the diffusion of action from momentum and
energy into wavelength and wavetime. You may be able to do something
with the simple differential equations on the first page at...