Quick question about the EFE's. When writing the einstein tensor [itex]G_{\mu\nu}=R_{\mu\nu}-\frac{1}{2}Rg_{\mu\nu}[/itex], and using the definition of the Ricci scalar [itex]R=g^{\mu\nu}R_{\mu\nu}[/itex], how does this not give you problems when you expand out [itex]R[/itex] so that the second term becomes [itex]-\frac{1}{2}g^{\mu\nu}R_{\mu\nu}g_{\mu\nu}=-2R_{\mu\nu}[/itex] when evaluating the trace, giving you the EFE's as [itex]R_{\mu\nu}=-4πGT_{\mu\nu}[/itex]?(adsbygoogle = window.adsbygoogle || []).push({});

Any help would be appreciated.

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# EFE's question regarding Ricci scalar

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