Demonstration 2 (israel): Reduction of Ricci to zero, calculation and simplification of the Kretschmann scalar in Israel coordinates.
> restart:
> grtw();
> qload(israel);
> grcalc(R(dn,dn),RiemSq);
Created definition for R(dn,dn,up,up)
> gralter(_,13);
Component simplification of a GRTensorII object:
Applying routine `Apply constraints repeatedly` to object R(dn,dn)
Applying routine `Apply constraints repeatedly` to object RiemSq
> grdisplay(_);
>