Does SR preserve the direction of light?

jk22
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does SR change the direction of light and if yes is it then possible to find a transformation keeping the velocity of light invariant and not only its speed ?
 
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jk22 said:
does SR change the direction of light and if yes is it then possible to find a transformation keeping the velocity of light invariant and not only its speed ?
I think just the identity transformation.
 
Any Lorentz boost will leave invariant the direction of light beams that are directed along the same axis; but it will change the direction of light beams that are not directed along the same axis. So a Lorentz boost along the x-axis would not change the direction of light beams traveling along the x axis; but it would change the direction of all other light beams.

Also, even light beams whose directions are not changed by a Lorentz boost will have their frequency changed.
 
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