Wave equation for Schwarzschild metric

AI Thread Summary
The discussion focuses on calculating the wave operator $$\nabla_{\mu}\nabla^{\mu} \Phi$$ for the Schwarzschild metric. The user has derived an expression for the wave operator but is uncertain about its accuracy and potential simplifications. Another participant recommends the book "Spacetime and Geometry" by Sean M. Carroll for further study on the topic. Concerns about forum rules regarding book recommendations are addressed, clarifying that suggesting books is acceptable as long as no illegal links are provided. The conversation highlights the balance between providing help and encouraging independent problem-solving in academic forums.
Arman777
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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
 
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Hello, @Arman777 . I am recently studying this problem. I would suggest Spacetime and geometry by Sean M. Carroll, especialy in pages 395 to 400.

Will I violate any rules in this forum if I just suggest a book?
 
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Likes PeroK and vanhees71
Of course not. Of course you violate rules, if you link to some illegal download-link to a copyrighted book.
 
vanhees71 said:
Of course not. Of course you violate rules, if you link to some illegal download-link to a copyrighted book.
Thanks! Sometimes I hesitate to answer in homework forum, because not only there are too many professors, but I am afraid I would give the answer directly which would violate the rules.
 
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Likes vanhees71 and PeroK
Don't worry about the "professors". They are also just human beings. Not giving directly the answer is also my problem with the homework forums, but it's of course much better to give only hints first and let the student find the solution him or herself.
 
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