Look at the full set of equations
Here is a table of all of the equations represented by the "Einstein
Equation". Note that all of the below equations are automatically satisfied
except for a single differential equation, which we must solve to get the
function g[r] that determines the spacetime metric.
In[19]:=
Table[eqn[-i,-j],{i,3},{j,3}]
Out[19]=
{{True, True, True}, {True, True, True},
-(g'[r] + r g''[r])
{True, True, ------------------- ==
g[r]
2 E r
k M DiracDelta[r] DiracDelta[theta]
-----------------------------------}}
g[r]
E r
The fact that all of the equations are satisfied except for the one we need to
solve means that our original choice of coordinates based on the rotational and
time translation symmetries was consistent with the stress tensor used above. A
lot of nasty work in physics can be avoided by understanding the symmetries of
the problem before doing the calculations! Same goes in life, I suppose. :-)
Up to Compute the equations
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