I have again a very specific question: I have a couple of Tensors, let's call them A[i] and B[i], that satisfy certain relations e.g. for A[i]:
PD[i]A[j]+PD[j]A[i]=0.
I would now like to use these relations in a very long expression that includes for example
...+PD[i][A[j]]B[-i]A[-j]*something_long_with_indices_being_contracted+...+PD[j][A[i]]B[-i]A[-j]*something_long_with_indices_being_contracted+...
such that, the two given terms vanish.
More specifically, I face the problem that the index names are potentially different, i.e. they could occur in a form like:
...+PD[q][A[r]]B[-q]A[-r]*something1+...+PD[j][A[i]]B[-i]A[-j]*something1+...
Is there an easy way to obtain such a replacement rule?
All the best.