Einstein’s eqn Gmn = (- 8pGN/c4) Tmn the relativistic generalization of Newton/Poisson eqn ??? = 4p GNr
Relativistic = same physics in all coordinates
Physics equations must be a tensor eqns
Tensor = object having definite transformation properties under coordinate transformation
What tensors for r , ? , and ??? ... ?
? ? metric tensor gmn = relativistic grav potential
Recall: gmn = diag (-1,1,1,1) for flat spacetime