Curvature Scalar
The curvature scalar is given by
where
is the Metric Tensor and 
is the Ricci Tensor.See also Curvature, Gaussian Curvature, Mean Curvature, Metric Tensor, Radius of Curvature,Ricci Tensor, Riemann-Christoffel Tensor- Resolution
- Resolution Class
- Resolution Modulus
- Resolvable
- Resolving Tree
- Resonance Overlap
- Resonance Overlap Method
- R-Estimate
- Restricted Divisor Function
- Restricted Growth Function
- Restricted Growth String
- Resultant
- Retardance
- Reuleaux Polygon
- Reuleaux Triangle
- Reversal
- Reverse Greedy Algorithm
- Reverse-Then-Add Sequence
- Reversion of Series
- Reznik's Identity
- Rhodonea
- Rhomb
- Rhombic Dodecahedral Number
- Rhombic Dodecahedron
- Rhombic Icosahedron