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/Tag.hpp"
       9             : #include "DataStructures/Tensor/TypeAliases.hpp"
      10             : 
      11             : /// \cond
      12             : namespace gsl {
      13             : template <typename>
      14             : struct not_null;
      15             : }  // namespace gsl
      16             : /// \endcond
      17             : 
      18             : namespace hydro {
      19             : 
      20             : namespace Tags {
      21             : /// \brief Tag containing the quadrupole moment.
      22             : ///
      23             : /// The quadrupole moment is defined as \f$\tilde{D} x^i x^j\f$
      24             : /// (equation 21 of \cite Shibata2003), with
      25             : /// \f$\tilde{D}=\sqrt{\gamma}\rho W\f$, $W$ being the Lorentz factor,
      26             : /// $\gamma$ being the determinant of the spatial metric, and
      27             : /// \f$x\f$ the coordinates in Frame Fr.
      28             : template <typename DataType, size_t Dim, typename Fr = Frame::Inertial>
      29           1 : struct QuadrupoleMoment : db::SimpleTag {
      30           0 :   using type = tnsr::ii<DataType, Dim, Fr>;
      31             : };
      32             : 
      33             : /// \brief Tag containing the first time derivative of the quadrupole moment.
      34             : ///
      35             : /// For the first derivative of the quadrupole moment, we use
      36             : /// \f$\tilde{D} (v^i x^j + x^i v^j)\f$ (equation 23 of \cite Shibata2003),
      37             : /// with \f$\tilde{D}=\sqrt{\gamma}\rho W\f$, $W$ being the Lorentz factor,
      38             : /// $\gamma$ being the determinant of the spatial metric, \f$x\f$ the
      39             : /// coordinates in Frame Fr, and \f$v\f$ the corresponding spatial velocity.
      40             : template <typename DataType, size_t Dim, typename Fr = Frame::Inertial>
      41           1 : struct QuadrupoleMomentDerivative : db::SimpleTag {
      42           0 :   using type = tnsr::ii<DataType, Dim, Fr>;
      43             : };
      44             : }  // namespace Tags
      45             : 
      46             : /// \brief Function computing the quadrupole moment.
      47             : ///
      48             : /// Computes the quadrupole moment, using
      49             : /// \f$\tilde{D} x^i x^j\f$ (equation 21 of \cite Shibata2003),
      50             : /// with \f$\tilde{D}=\sqrt{\gamma}\rho W\f$, $W$ being the Lorentz factor,
      51             : /// $\gamma$ being the determinant of the spatial metric, and
      52             : /// \f$x\f$ the coordinates in Frame Fr. Result of calculation stored in result.
      53             : template <typename DataType, size_t Dim, typename Fr = Frame::Inertial>
      54           1 : void quadrupole_moment(
      55             :     const gsl::not_null<tnsr::ii<DataType, Dim, Fr>*> result,
      56             :     const Scalar<DataType>& tilde_d,
      57             :     const tnsr::I<DataType, Dim, Fr>& coordinates);
      58             : 
      59             : /// \brief Function computing the first time derivative of the
      60             : /// quadrupole moment.
      61             : ///
      62             : /// Computes the first time derivative of the quadrupole moment, using
      63             : /// \f$\tilde{D} (v^i x^j + x^i v^j)\f$ (equation 23 of \cite Shibata2003),
      64             : /// with \f$\tilde{D}=\sqrt{\gamma}\rho W\f$, $W$ being the Lorentz factor,
      65             : /// $\gamma$ being the determinant of the spatial metric, \f$x\f$ the
      66             : /// coordinates in Frame Fr, and \f$v\f$ the corresponding spatial velocity.
      67             : /// Result of calculation stored in result.
      68             : template <typename DataType, size_t Dim, typename Fr = Frame::Inertial>
      69           1 : void quadrupole_moment_derivative(
      70             :     const gsl::not_null<tnsr::ii<DataType, Dim, Fr>*> result,
      71             :     const Scalar<DataType>& tilde_d,
      72             :     const tnsr::I<DataType, Dim, Fr>& coordinates,
      73             :     const tnsr::I<DataType, Dim, Fr>& spatial_velocity);
      74             : 
      75             : } // namespace hydro