Line data    Source code

       1           0 : // Distributed under the MIT License.
       2             : // See LICENSE.txt for details.
       3             : 
       4             : #pragma once
       5             : 
       6             : #include <cstddef>
       7             : 
       8             : #include "DataStructures/DataBox/Prefixes.hpp"
       9             : #include "DataStructures/DataBox/Tag.hpp"
      10             : #include "DataStructures/DataVector.hpp"
      11             : #include "DataStructures/Tensor/Tensor.hpp"
      12             : #include "Evolution/Systems/GeneralizedHarmonic/Tags.hpp"
      13             : #include "NumericalAlgorithms/LinearOperators/PartialDerivatives.hpp"
      14             : #include "PointwiseFunctions/GeneralRelativity/Tags.hpp"
      15             : #include "Utilities/ContainerHelpers.hpp"
      16             : #include "Utilities/Gsl.hpp"
      17             : #include "Utilities/TMPL.hpp"
      18             : 
      19             : // IWYU pragma: no_forward_declare Tags::deriv
      20             : 
      21             : /// \cond
      22             : namespace domain {
      23             : namespace Tags {
      24             : template <size_t Dim, typename Frame>
      25             : struct Coordinates;
      26             : }  // namespace Tags
      27             : }  // namespace domain
      28             : class DataVector;
      29             : template <typename X, typename Symm, typename IndexList>
      30             : class Tensor;
      31             : /// \endcond
      32             : 
      33             : namespace gh {
      34             : /// @{
      35             : /*!
      36             :  * \ingroup GeneralRelativityGroup
      37             :  * \brief Computes the time derivative of the spacetime metric from the
      38             :  * generalized harmonic quantities \f$\Pi_{a b}\f$, \f$\Phi_{i a b}\f$, and the
      39             :  * lapse \f$\alpha\f$ and shift \f$\beta^i\f$.
      40             :  *
      41             :  * \details Computes the derivative as:
      42             :  *
      43             :  * \f{align}{
      44             :  * \partial_t g_{a b} = \beta^i \Phi_{i a b} - \alpha \Pi_{a b}.
      45             :  * \f}
      46             :  */
      47             : template <typename DataType, size_t SpatialDim, typename Frame>
      48           1 : void time_derivative_of_spacetime_metric(
      49             :     gsl::not_null<tnsr::aa<DataType, SpatialDim, Frame>*> dt_spacetime_metric,
      50             :     const Scalar<DataType>& lapse,
      51             :     const tnsr::I<DataType, SpatialDim, Frame>& shift,
      52             :     const tnsr::aa<DataType, SpatialDim, Frame>& pi,
      53             :     const tnsr::iaa<DataType, SpatialDim, Frame>& phi);
      54             : 
      55             : template <typename DataType, size_t SpatialDim, typename Frame>
      56           1 : tnsr::aa<DataType, SpatialDim, Frame> time_derivative_of_spacetime_metric(
      57             :     const Scalar<DataType>& lapse,
      58             :     const tnsr::I<DataType, SpatialDim, Frame>& shift,
      59             :     const tnsr::aa<DataType, SpatialDim, Frame>& pi,
      60             :     const tnsr::iaa<DataType, SpatialDim, Frame>& phi);
      61             : /// @}
      62             : }  // namespace gh