8*pi in the Einstein field equations?

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SUMMARY

The discussion centers on the necessity of the factor 8π in the Einstein field equations, specifically in the formulation R_{\mu\nu}-\frac{1}{2}Rg_{\mu\nu}+\Lambda g_{\mu\nu}=\frac{8\pi G}{c^4}T_{\mu\nu}. This factor ensures that the equations align with Newtonian gravity in the appropriate limit. The inclusion of 8π is crucial for maintaining consistency between general relativity and classical physics, particularly in the context of gravitational interactions.

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A typical formulation of the Einstein equations is

[tex]R_{\mu\nu}-\frac{1}{2}Rg_{\mu\nu}+\Lambda g_{\mu\nu}=\frac{8\pi G}{c^4}T_{\mu\nu}[/tex]

The [itex]\frac{G}{c^4}[/itex] make the units work out. What about the 8*pi? Why is this necessary?
 
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The field equations have to agree with Newtonian gravity in the Newtonian limit.
 
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