Derivation of the wave equation on a curved space-time

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Homework Help Overview

The discussion revolves around the derivation of the wave equation in the context of curved spacetime, specifically focusing on the electromagnetic tensor and the implications of minimal coupling.

Discussion Character

  • Exploratory, Conceptual clarification, Assumption checking

Approaches and Questions Raised

  • Participants explore the relationship between covariant derivatives and the electromagnetic tensor, questioning the clarity of the starting point for the derivation. There is a mention of the reduction of expressions in Minkowski coordinates, and one participant reflects on the importance of the commutation of covariant derivatives.

Discussion Status

The discussion is active, with participants seeking clarification on the initial conditions and expressions involved. Some guidance has been provided regarding the relationship between covariant derivatives and the electromagnetic tensor, but there is no explicit consensus on the approach to take.

Contextual Notes

There is a noted lack of clarity regarding the starting point of the derivation, which may affect the understanding of the problem. Additionally, the level of physics being discussed is questioned, indicating a potential range of familiarity among participants.

Woolyabyss
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Homework Statement
Problem attached as image
Relevant Equations
## \nabla^a F_{ab} = 0 ##
## \nabla_a F_{bc} + \nabla_b F_{ca} + \nabla_c F_{ab} = 0 ##
I'm confused by this question, from minimal coupling shouldn't the answer simply be ## \nabla^a \nabla_a F_{bc} = 0 ##? Any help would be appreciated.

EDIT: I should also point out ##F_{ab}## is the EM tensor.
 

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You have not given the starting point and so the goal is unclear. Both expressions reduce to ##\partial^\lambda\partial_\lambda F_{\mu\nu}=0## in Minkowski coordinates on flat spacetime.
 
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Orodruin said:
You have not given the starting point and so the goal is unclear. Both expressions reduce to ##\partial^\lambda\partial_\lambda F_{\mu\nu}=0## in Minkowski coordinates on flat spacetime.
Thanks for the reply, I managed to work out the answer my issue turned out to be I wasn't taking into account that covariant derivatives don't commute.
 
Out of curiosity - what level of Physics is this?
 
Physics?
I thought it was Greek. ;)
 

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