converts all curvature tensors of rank two and contracted Riemann tensors in expr to Ricci tensors and scalars.
ToRicci[expr, cd]
converts only for curvature tensors of the covariant derivative cd.
  • The curvature tensors of rank two are the tracefree Ricci tensor, the Einstein tensor, the Schouten tensor, the cosmological Einstein tensor, and the cosmological Schouten tensor.