$RicciSign

• $RicciSign defines the global sign of the Ricci tensor from contraction of the Riemann tensor: Ricci[-a,-b] = $RicciSign Riemann[-a,-c,-b,c].

• The default value is +1, following Wald's conventions, as usual.
• See: Section 4.5.
• See also: DefCovD, Ricci.
• New in version 0.
• Last update: 14-V-2008 for version 0.9.5 of xTensor`.

Created by Mathematica  (May 16, 2008)