- #1
lailola
- 46
- 0
Let be a photon in a circular orbit (r=3M). I want to know the period measured by a stationary observer at this radius.
Because we are working with a photon we cannot 'talk' about proper time, that's why I don't understand how can I calculate this.
If I had a massive particle I could do it (just finding an expression for [itex]\frac{d\phi}{d\tau}[/itex] and then calculating [itex]\Delta\tau[/itex] for [itex]\Delta\phi=2\pi[/itex].
Thanks for any help
Because we are working with a photon we cannot 'talk' about proper time, that's why I don't understand how can I calculate this.
If I had a massive particle I could do it (just finding an expression for [itex]\frac{d\phi}{d\tau}[/itex] and then calculating [itex]\Delta\tau[/itex] for [itex]\Delta\phi=2\pi[/itex].
Thanks for any help