Talk:Weak-field approximation/to do

• merge as suggested (see longer todo list in other existing article),
• explain abstract index notation (tensor indices from 0,...,3), distinguish notationally between space and spacetime indices,
• explain that more generally, weak field limits can help one identify qualitative meaning of a parameter which has arisen in a solution of EFE from assuming some symmetry Ansatz, as in Schwarzschild.