Specific proof of the Riemann tensor for FRW metric

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The discussion centers on proving the expression for the Riemann tensor in the context of the Friedmann-Robertson-Walker (FRW) metric, specifically Rijkl = k/R^2 * (gik gjl - gil gjk), where k can take values of 0, +1, or -1. Participants highlight the challenge of deriving the Christoffel symbols from the metric g_ij without resorting to Killing vectors, emphasizing the need to use the definitions of Christoffel symbols and Riemann tensors. The conversation includes requests for clarification on the metric and guidance on showing work in the derivation process. Overall, the thread reflects a collaborative effort to tackle the complexities of tensor calculus in cosmological contexts. The focus remains on finding a solution through mathematical rigor.
Chromatic_Universe
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Homework Statement


Prove Rijkl= k/R2 * (gik gjl-gil gjk) where gik is the 3 metric for FRW universe and K =0,+1,-1, and i,j=1,2,3, that is, spatial coordinates.
.

Homework Equations


The Christoffel symbol definition:
Γμνρ = ½gμσ(∂ρgνσ+∂νgρσ-∂σgνρ)
and the Riemann tensor definition:
Rμνσρ = ∂σΓμρν-∂ρΓμσνμσλΓλρνμρλΓλσν
and the FRLW metric, in the section:
Reduced-circumference polar coordinates (under general metric section)

The Attempt at a Solution


I cannot come to the general expression for the Christoffel symbols using g_ij. But the expression can be derived using Killing vectors for maximally symmetric space. For the FRW universe(homogeneous and isotropic), the same holds true, but I am finding it difficult to get to this expression without using Killing vectors, only using the definition of Christoffel symbols and Riemann tensors.
 
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Chromatic_Universe said:

Homework Statement


Prove Rijkl= k/R2 * (gik gjl-gil gjk) where gik is the 3 metric for FRW universe and K =0,+1,-1
.

Homework Equations


The Christoffel symbol definition and the Riemann tensor definition

The Attempt at a Solution


I cannot come to the general expression for the Christoffel symbols using g_ij.

Well, to get started, can you write down the metric, and the definition of the Christoffel symbols and Riemann tensors? You have to show some work.
 
stevendaryl said:
Well, to get started, can you write down the metric, and the definition of the Christoffel symbols and Riemann tensors? You have to show some work.
Edited the question! Thanks!
 

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