Einstein Equation with Cosmological Constant & Variable x^u

alejandrito29
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with the action \int (k(R- 2 \Lambda)+L_m) \sqrt{g} the Einstein equation is:

R_{uv}-\frac{1}{2}R g_{uv}- \Lambda g_{uv} = k' T_{uv}

How is the Einstein equation if \Lambda=\Lambda(x^u)? with x^u a coordinate
 
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The same. You derive the Einstein equations with a variation with respect to the metric, not the coordinates. So you obtain the Einstein equations

<br /> R_{uv}-\frac{1}{2}R g_{uv}- \Lambda(x) g_{uv} = ksingle-quote T_{uv}<br />

However, you're in serieus trouble with energy conservation. A constant CC is allowed, because then

<br /> \nabla_{\rho}(\Lambda g_{\mu\nu}) = \Lambda \nabla_{\rho}g_{\mu\nu}=0<br />

If Lambda is general, energy conservation is spoiled.
 
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