- #1
stunner5000pt
- 1,461
- 2
Explain why elight emitted at a point inside the Scwarzschild radius (r<a) cannot be seen by a distant observer. (by one at r-> infinity)
well we know the trajectory of a photon is given by
[tex] \dot{r}^2 = c^2 \lambda^2 - \left( 1 - \frac{a}{r}\right) \frac{J^2}{r^2} [/tex]
where J repsents the angular momentum in units of mass
lambda is [tex] \lambda = \dot{t} \left( 1 - \frac{a}{r} \right) [/tex]
so when r < a does the expression for r dot become imaginary? Is that what i am aiming to prove?
well we know the trajectory of a photon is given by
[tex] \dot{r}^2 = c^2 \lambda^2 - \left( 1 - \frac{a}{r}\right) \frac{J^2}{r^2} [/tex]
where J repsents the angular momentum in units of mass
lambda is [tex] \lambda = \dot{t} \left( 1 - \frac{a}{r} \right) [/tex]
so when r < a does the expression for r dot become imaginary? Is that what i am aiming to prove?