Dear Kasper, thank you for the answer. Actually, as you pointed, the equal sign assigns the value to A00
. However, it seems that I cannot use the value for further manipulations.
I'm trying to write a demo notebook for students, and it occurs to me that it might be possible to solve the Schwarzschild spacetime. I got inspired by your notebook, but used
ss:= { g_{t t} = - \exp(A),
g_{r r} = \exp(B),
g_{\theta\theta} = r**2,
g_{\phi\phi}=r**2 \sin(\theta)**2 }.
for the metric.
After calculating the Ricci tensor rc
, I call the components,
from cdb.core.component import *
r00=get_component(rc, $t,t$)[1];
r11=get_component(rc, $r,r$)[1];
but then I cannot use those expressions (it seems)
See image