Line data    Source code

       1            0 : // Distributed under the MIT License.
       2              : // See LICENSE.txt for details.
       3              : 
       4              : #pragma once
       5              : 
       6              : #include "DataStructures/DataBox/Tag.hpp"
       7              : #include "DataStructures/Tensor/Tensor.hpp"
       8              : #include "DataStructures/Tensor/TypeAliases.hpp"
       9              : #include "Evolution/Systems/CurvedScalarWave/Tags.hpp"
      10              : #include "PointwiseFunctions/GeneralRelativity/Surfaces/TagsDeclarations.hpp"
      11              : #include "Utilities/Gsl.hpp"
      12              : #include "Utilities/TMPL.hpp"
      13              : 
      14              : namespace ScalarTensor {
      15              : 
      16              : /// @{
      17              : /*!
      18              :  * \brief The scalar charge per unit solid angle.
      19              :  *
      20              :  * \details This function calculates the integrand of:
      21              :  * \f{align*}
      22              :  * q = - \dfrac{1}{4 \pi} \oint dA \Phi_i n^{i},
      23              :  * \f}
      24              :  * where \f$ n^{i} \f$ is the unit (outward) normal of the surface.
      25              :  *
      26              :  * For a spherically symmetric scalar, this value will coincide with the value
      27              :  * as extracted from the $r^{-1}$ decay in
      28              :  * \f[ \Psi \sim \phi_\infty + q / r + \cdots~. \f]
      29              :  */
      30            1 : void scalar_charge_integrand(const gsl::not_null<Scalar<DataVector>*> result,
      31              :                              const tnsr::i<DataVector, 3>& phi,
      32              :                              const tnsr::I<DataVector, 3>& unit_normal_vector);
      33              : /// @}
      34              : 
      35              : } // namespace ScalarTensor
      36              : 
      37            0 : namespace ScalarTensor::StrahlkorperScalar::Tags {
      38              : 
      39              : /*!
      40              :  * \brief The scalar charge per unit area.
      41              :  *
      42              :  * \details This tag holds the integrand of:
      43              :  * \f{align*}
      44              :  * q = - \dfrac{1}{4 \pi} \oint dA \Phi_i n^{i},
      45              :  * \f}
      46              :  * where \f$ n^{i} \f$ is the unit (outward) normal of the surface.
      47              :  *
      48              :  * For a spherically symmetric scalar, this value will coincide with the value
      49              :  * as extracted from the $r^{-1}$ decay in
      50              :  * \f[ \Psi \sim \phi_\infty + q / r + \cdots~. \f]
      51              :  */
      52            1 : struct ScalarChargeIntegrand : db::SimpleTag {
      53            0 :   using type = Scalar<DataVector>;
      54              : };
      55              : 
      56              : /*!
      57              :  * \brief Compute tag for the scalar charge per unit area.
      58              :  *
      59              :  * \see ScalarTensor::StrahlkorperScalar::Tags::ScalarChargeIntegrand
      60              :  */
      61            1 : struct ScalarChargeIntegrandCompute : ScalarChargeIntegrand, db::ComputeTag {
      62            0 :   static constexpr size_t Dim = 3;
      63            0 :   using base = ScalarChargeIntegrand;
      64            0 :   static constexpr auto function = &ScalarTensor::scalar_charge_integrand;
      65            0 :   using argument_tags =
      66              :       tmpl::list<CurvedScalarWave::Tags::Phi<Dim>,
      67              :                  ylm::Tags::UnitNormalVector<Frame::Inertial>>;
      68            0 :   using return_type = Scalar<DataVector>;
      69              : };
      70              : 
      71              : }  // namespace ScalarTensor::StrahlkorperTags