>>13800862The axiom of inertial frames is that the laws of physics dont change, which is not the same as saying nothing changes. Relative speeds of specific items will of course change, as well as the values of magnetic and electric fields, frequencies and many other things, but the changes are not random but are supposed to still be compatible with the same laws of physics.
Dont too defensive, its only an axiom. The truth is you can't tell how nature ought ti behave in a frame of reference where you haven't perform an experiment yourself. Its like this idea that physical constants might be different in different parts of the universe or in different eras, we can't know.
