$RiemannSign

• $RiemannSign defines the global sign of the Riemann tensor from derivatives of a connection: Riemann[-a,-b,-c,d] = $RiemannSign ( PD[-a][Christoffel[d,-b,-c] + ... )

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

Created by Mathematica  (May 16, 2008)