- #1
latentcorpse
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My notes say that a photon traveling from a high altitude to an observer at low altitude appears to have a higher frequency i.e. gravitational blue shift.
now I am having trouble getting this:
the strong equivalence principle says we can substitute this "laboratory" with a laboratory that is undergoing uniform acceleration -g in deep space.
i then drew a box with the photon being emitted from the roof and traveling towards the floor. the box is moving downward with an acceleration g. so as we are moving away from the source we should use the following formula for gravitational doppler effect:
[itex]\nu^{obs}=\nu^{source} \sqrt{\frac{1-\beta}{1+\beta}}[/itex] where [itex]\beta=\frac{v}{c}[/itex] which predicts a gravitational redshift as [itex]\beta[/itex] is positive as we are moving away from the source with velocity v. I'm messing up somewhere but i can't see it.
help!
now I am having trouble getting this:
the strong equivalence principle says we can substitute this "laboratory" with a laboratory that is undergoing uniform acceleration -g in deep space.
i then drew a box with the photon being emitted from the roof and traveling towards the floor. the box is moving downward with an acceleration g. so as we are moving away from the source we should use the following formula for gravitational doppler effect:
[itex]\nu^{obs}=\nu^{source} \sqrt{\frac{1-\beta}{1+\beta}}[/itex] where [itex]\beta=\frac{v}{c}[/itex] which predicts a gravitational redshift as [itex]\beta[/itex] is positive as we are moving away from the source with velocity v. I'm messing up somewhere but i can't see it.
help!