My first question, so sorry if it's in the wrong forum.(adsbygoogle = window.adsbygoogle || []).push({});

I'm trying to understand the Newtonian weak field approximations to general relativity. I can't see why, if the Schwarzschild metric (which can describe the gravitational field around the Sun) is a vacuum solution ([itex]T_{\mu\nu}=0[/itex] ) , do textbooks state that [itex]T=\rho c^{2}[/itex] when approximating Poisson's Equation (which also describes the gravitational field around the Sun) from the Einstein Field Equations?

Thank you .

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# Value of energy-momentum tensor in weak field approximations

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