Line data    Source code

       1           0 : // Distributed under the MIT License.
       2             : // See LICENSE.txt for details.
       3             : 
       4             : #pragma once
       5             : 
       6             : #include <cmath>
       7             : #include <cstddef>
       8             : #include <cstdint>
       9             : #include <utility>
      10             : 
      11             : #include "DataStructures/DataBox/Prefixes.hpp"
      12             : #include "DataStructures/DataBox/Tag.hpp"
      13             : #include "DataStructures/Tensor/EagerMath/DeterminantAndInverse.hpp"
      14             : #include "DataStructures/Tensor/Tensor.hpp"
      15             : #include "DataStructures/VariablesTag.hpp"
      16             : #include "NumericalAlgorithms/LinearOperators/PartialDerivatives.hpp"
      17             : #include "PointwiseFunctions/GeneralRelativity/Tags.hpp"
      18             : #include "Utilities/ContainerHelpers.hpp"
      19             : #include "Utilities/Gsl.hpp"
      20             : #include "Utilities/TMPL.hpp"
      21             : #include "Utilities/TaggedTuple.hpp"
      22             : 
      23             : /// \ingroup GeneralRelativityGroup
      24             : /// Holds functions related to general relativity.
      25             : namespace gr {
      26             : /// @{
      27             : /*!
      28             :  * \brief Computes spacetime normal one-form from lapse.
      29             :  *
      30             :  * \details If \f$\alpha\f$ is the lapse, then
      31             :  *
      32             :  * \f{align}
      33             :  *     n_t &= - \alpha \\
      34             :  *     n_i &= 0
      35             :  * \f}
      36             :  *
      37             :  * is computed.
      38             :  */
      39             : template <typename DataType, size_t SpatialDim, typename Frame>
      40           1 : void spacetime_normal_one_form(
      41             :     gsl::not_null<tnsr::a<DataType, SpatialDim, Frame>*> normal_one_form,
      42             :     const Scalar<DataType>& lapse);
      43             : 
      44             : template <typename DataType, size_t SpatialDim, typename Frame>
      45           1 : tnsr::a<DataType, SpatialDim, Frame> spacetime_normal_one_form(
      46             :     const Scalar<DataType>& lapse);
      47             : /// @}
      48             : 
      49             : namespace Tags {
      50             : /*!
      51             :  * \brief Compute item for spacetime normal oneform \f$n_a\f$ from
      52             :  * the lapse \f$\alpha\f$.
      53             :  *
      54             :  * \details Can be retrieved using `gr::Tags::SpacetimeNormalOneForm`.
      55             :  */
      56             : template <typename DataType, size_t SpatialDim, typename Frame>
      57           1 : struct SpacetimeNormalOneFormCompute
      58             :     : SpacetimeNormalOneForm<DataType, SpatialDim, Frame>,
      59             :       db::ComputeTag {
      60           0 :   using argument_tags = tmpl::list<Lapse<DataType>>;
      61             : 
      62           0 :   using return_type = tnsr::a<DataType, SpatialDim, Frame>;
      63             : 
      64           0 :   static constexpr auto function =
      65             :       static_cast<void (*)(gsl::not_null<tnsr::a<DataType, SpatialDim, Frame>*>,
      66             :                            const Scalar<DataType>&)>(
      67             :           &spacetime_normal_one_form<DataType, SpatialDim, Frame>);
      68             : 
      69           0 :   using base = SpacetimeNormalOneForm<DataType, SpatialDim, Frame>;
      70             : };
      71             : }  // namespace Tags
      72             : }  // namespace gr