Deriving 8πG/c^4 in General Relativity

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Hello All,

In GR the factor 8piG/c^4. I want to understand how the term is derived? I mean to say that is this related to Friedmann Equation. How the factor actually comes into Einstein's field equation?

I am sorry if I am unable frame the question properly.

Thanks.

-- Shounak
 
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The G/c^4 term is there for dimensional consistency. The 8 pi is required so that GR reduces to Newtonian gravity in the appropriate limit.
 

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