- #1
pleasehelpmeno
- 157
- 0
Hi can anyone explain how to find [itex]\delta \sqrt{-g}[/itex] when varying with respect to the metric tensor [itex]g^{\mu\nu}[/itex]. i.e why is it equal to [itex]\delta \sqrt{-g} = -\frac{1}{2} \sqrt{-g}g_{\mu\nu} \delta g^{\mu \nu} [/itex]