Weyl Tensor Notation in Dimension 4

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The discussion focuses on the Weyl Tensor notation in four dimensions, with a participant sharing their formulation of the tensor. They present their version of the Weyl Tensor, comparing it to the one found on Wikipedia. Other participants confirm the accuracy of the formulation and suggest verifying it by contracting the tensor. The original poster successfully contracts the tensor and confirms that the result is zero, indicating correctness. The conversation emphasizes the importance of verifying tensor properties in differential geometry.
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Hi,

I'm getting used to the anti-symmetric bracket notation used with indices and I can't seem to find the Weyl Tensor written fully out. So I want to make sure I get it. Here is my attempt in dimension 4.

W_{abcd}=R_{abcd}-\frac{1}{2}\left[g_{ac}R_{db}-g_{ad}R_{cb}-g_{bc}R_{da}+g_{bd}R_{ca}\right]+\frac{1}{6}R\left(g_{ac}g_{db}-g_{ad}g_{cb}\right)

It is written on wiki as

W_{abcd}=R_{abcd}-\frac{2}{n-2}\left(g_{a[c}R_{d]b}-g_{b[c}R_{d]a}\right)+\frac{2}{(n-1)(n-2)}R\, g_{a[c}g_{d]b}

Did I do it correct for n=4?

Thanks,
 
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Looks good to me.
 
Looks right. Try contracting, gacWabcd, and see if you get 0.
 
cristo said:
Looks good to me.

Bill_K said:
Looks right. Try contracting, gacWabcd, and see if you get 0.

Thanks, I got 0 when I contracted.
 
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