ArthurB
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I have some problems using this definition, maybe because it's not valid in every coordinate system:
<br /> T^{\mu\nu} = (\epsilon + p) \frac{dx^{\mu}}{ds} \frac{dx^{\nu}}{ds} -p g^{\mu\nu}<br />
since in cylindrical coordinates
<br /> x^0 =t \qquad x^1 =\rho \qquad x^2 = \phi \qquad x^3 =z<br />
using weyl metric
<br /> g_{00}= e^{2u} \qquad g_{11}=-e^{2v-2u} \qquad g_{22}=-\rho^2 e^{-2u} \qquad g_{33}=-e^{2v-2u} \qquad u=u(\rho,z) \qquad v=v(\rho,z)<br />
I obtain
<br /> T_{11}=T_{33}<br />
but from the definition of the einstein tensor I obtain
<br /> G_{11}=-G_{33}<br />
but einstein equation says
<br /> G_{\mu\nu}=8\pi k T_{\mu\nu}<br />
which in this case then implies
<br /> T_{11}=-T_{33}<br />
in contraddiction with the result obtained from the first formula.
can anyone explain?
<br /> T^{\mu\nu} = (\epsilon + p) \frac{dx^{\mu}}{ds} \frac{dx^{\nu}}{ds} -p g^{\mu\nu}<br />
since in cylindrical coordinates
<br /> x^0 =t \qquad x^1 =\rho \qquad x^2 = \phi \qquad x^3 =z<br />
using weyl metric
<br /> g_{00}= e^{2u} \qquad g_{11}=-e^{2v-2u} \qquad g_{22}=-\rho^2 e^{-2u} \qquad g_{33}=-e^{2v-2u} \qquad u=u(\rho,z) \qquad v=v(\rho,z)<br />
I obtain
<br /> T_{11}=T_{33}<br />
but from the definition of the einstein tensor I obtain
<br /> G_{11}=-G_{33}<br />
but einstein equation says
<br /> G_{\mu\nu}=8\pi k T_{\mu\nu}<br />
which in this case then implies
<br /> T_{11}=-T_{33}<br />
in contraddiction with the result obtained from the first formula.
can anyone explain?
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