- #1
- 2,168
- 193
- Homework Statement
- Wave equation for Schwarzschild metric
- Relevant Equations
- GR equations
I am trying to find the $$\nabla_{\mu}\nabla^{\mu} \Phi$$ for $$ds^2 = (1 - \frac{2M}{r})dt^2 + (1 - \frac{2M}{r})^{-1}dr^2 + r^2d\Omega^2$$
I have did some calculations by using
$$\nabla_{\mu}\nabla^{\mu}\Phi = \frac{1}{\sqrt{-g}}\partial_{\mu}(\sqrt{-g}g^{\mu \nu}\partial_{\nu}\Phi)$$
and I have found
$$\nabla_{\mu}\nabla^{\mu} \Phi = [g^{tt}\partial^2_t + 2(\frac{1}{r} - \frac{M}{r^2})\partial_r + g^{rr}\partial^2_r + \frac{cot(\theta)}{r^2}\partial_{\theta} + g^{\theta \theta}\partial^2_{\theta} + g^{\phi \phi}\partial^2_{\phi}]\Phi$$
but I am not sure that is this true or it can be further simplified ? Any ideas
I have did some calculations by using
$$\nabla_{\mu}\nabla^{\mu}\Phi = \frac{1}{\sqrt{-g}}\partial_{\mu}(\sqrt{-g}g^{\mu \nu}\partial_{\nu}\Phi)$$
and I have found
$$\nabla_{\mu}\nabla^{\mu} \Phi = [g^{tt}\partial^2_t + 2(\frac{1}{r} - \frac{M}{r^2})\partial_r + g^{rr}\partial^2_r + \frac{cot(\theta)}{r^2}\partial_{\theta} + g^{\theta \theta}\partial^2_{\theta} + g^{\phi \phi}\partial^2_{\phi}]\Phi$$
but I am not sure that is this true or it can be further simplified ? Any ideas