RiemannTensor

Riemann curvature tensor.

class gravica.riemann.RiemannTensor(christoffel)

Bases: object

Riemann curvature tensor \(R^a_{\ bcd}\).

\[R^a_{\ bcd} = \partial_c\,\Gamma^a_{\ db} - \partial_d\,\Gamma^a_{\ cb} + \Gamma^a_{\ ce}\,\Gamma^e_{\ db} - \Gamma^a_{\ de}\,\Gamma^e_{\ cb}\]
classmethod from_metric(metric)

Build from a MetricTensor.

Return type:

RiemannTensor

property components: list[list[list[list[Expression]]]]

\(R^a_{\ bcd}\) indexed as [a][b][c][d].

fully_contravariant(a, b, c, d)

\(R^{abcd} = g^{ae}\,g^{bf}\,g^{cg}\,g^{dh}\,R_{efgh}\).

Return type:

Expression

fully_covariant(a, b, c, d)

\(R_{abcd} = g_{ae}\,R^e_{\ bcd}\).

Return type:

Expression