- Added RicciToRiemann.
- Added KretschmannToRiemann.
- ToRiemann also converts rank-2 curature tensors if the curvature relations are not enabled.
- ToRicci also converts contractions of Riemann tensors to Ricci tensors even if the curvature relations are not enabled.
- IndexConfigurations gives correct results for expressions with more than one tangent bundle.
- EulerDensity is faster, and takes the option Verbose.
- xTras now needs xTensor 1.1.1.
- AllContractions automatically parallelizes on Mathematica 8 or newer.
- AllContractions has an improved algorithm.
- AllContractions directly calls the external xPerm executable, which makes it about 5x faster.
- ConstantSymbolsOf now takes multiple arguments.
- RiemannSimplification's error-message is more human-readable.
- xTras now requires xTensor 1.1.0.
- Products of symmetrized derivatives that commutate are now fully canonicalized.
- Improved speed of perturbations of symmetrized derivatives.
- Fixed two PrintAs related issues.
- FromIndexFree is now compatible with $AutoSymmetrizeCovDs = True.
- CollectTensors is more verbose while simplifying coefficients.
- Symmetrized derivatives use the chain rule on scalar functions.
- Improved speed of SymmetrizeCovDs in some situations.
- SymmetrizeCovDs strips all dummy indices before caching.
- VarD on symmetrized derivatives w.r.t. to another derivative works.
- Symmetrized covariant derivatives pass Validate.
- CollectTensors is faster on expressions that are (partially) collected.
- TensorWrapper is much faster on large products (was exponential in the number of terms, is now linear).
- Fixed warning message in SolveTensors.
- Added the function ConstantSymbolsOf.
- Added possibility (controlled by the variable $AutoSymmetrizeCovDs)
to automatically symmetrize covariant derivatives.
- Added caching to SymmetrizeCovDs, controlled by the "UseCache" option.
- Improved algorithm for symmetrizing covariant derivatives in the case
when there is no torsion and the derivative is metric-compatible.
- Perturbation no longer expands symmetrized covariant derivatives.
- Added functions for symmetrizing covariant derivatives (SymmetrizeCovDs and ExpandSymCovDs).
- Added the symmetrized Riemann tensor.
- Added the function ToRiemann.
- RiemannYoungProject only projects if the Riemann tensor has its full symmetries; otherwise it does nothing.
- RiemannYoungProject also projects Weyl and symmetrized Riemann tensors.
- TableauSymmetric now inherits the value of its option ManifestSymmetry from YoungSymmetrize.
This is a small point release, adding just one function:
- Added GradChristoffelToRiemann, which converts partial derivatives of Christoffel symbols to Riemann tensors.
This is a small bugfix release. The changes are:
- Defining a metric with PD as its Levi-Civita derivative is no longer broken.
- Extra curvature tensors Schouten, SchoutenCC, and EinsteinCC tensors are defined only when there
is curvature. Furthermore, they become non-symmetric when there is torsion, and are properly
extended, projected, and orthogonalized when needed.
- Added torsion to the RHS of the contracted Bianchi identities returned by CurvatureRelationsBianchi.