# Curved and Flat Indices

+1 vote

However the indices chapter has no mention regarding "curved" and "flat".
Are these just names or is there more to it? The Fierz transformation problem
has something like

{\mu,\nu,\rho}::Indices(curved, position=fixed).
{m,n,p,q,r,s,t,u,v}::Indices(flat, position=independent).

I don't understand the function of curved and flat

 {\mu,\nu,\rho}::Indices(name=curved, position=fixed).