Sigma2.hpp

#pragma once
#include "Angular/Angular.hpp"
#include "Coulomb/Coulomb.hpp"
#include "Wavefunction/DiracSpinor.hpp"
#include <vector>
 
namespace MBPT {
 
enum class Denominators { RS, BW };
 
 
std::pair<std::vector<DiracSpinor>, std::vector<DiracSpinor>>
split_basis(const std::vector<DiracSpinor> &basis, double E_Fermi,
            int min_n_core = 1, int max_n_excited = 999);
 
 
double Sk_vwxy(int k, const DiracSpinor &v, const DiracSpinor &w,
               const DiracSpinor &x, const DiracSpinor &y,
               const Coulomb::QkTable &qk, const std::vector<DiracSpinor> &core,
               const std::vector<DiracSpinor> &excited,
               const Angular::SixJTable &SixJ,
               Denominators denominators = Denominators::BW);
 
bool Sk_vwxy_SR(int k, const DiracSpinor &v, const DiracSpinor &w,
                const DiracSpinor &x, const DiracSpinor &y);
 
int number_below_Fermi(const DiracSpinor &i, const DiracSpinor &j,
                       const DiracSpinor &k, const DiracSpinor &l,
                       double eFermi);
 
std::pair<int, int> k_minmax_S(const DiracSpinor &v, const DiracSpinor &w,
                               const DiracSpinor &x, const DiracSpinor &y);
 
std::pair<int, int> k_minmax_S(int twoj_v, int twoj_w, int twoj_x, int twoj_y);
 
 
template <class CoulombIntegral> // CoulombIntegral may be YkTable or QkTable
double Sigma_vw(const DiracSpinor &v, const DiracSpinor &w,
                const CoulombIntegral &qk, const std::vector<DiracSpinor> &core,
                const std::vector<DiracSpinor> &excited,
                //const Angular::SixJTable *const SixJ = nullptr,
                int max_l_internal = 99,
                std::optional<double> ev = std::nullopt);
 
double e_bar(int kappa_v, const std::vector<DiracSpinor> &excited);
 
//==============================================================================
//==============================================================================
 
namespace InternalSigma {
double S_Sigma2_ab(int k, const DiracSpinor &v, const DiracSpinor &w,
                   const DiracSpinor &x, const DiracSpinor &y,
                   const Coulomb::QkTable &qk,
                   const std::vector<DiracSpinor> &core,
                   const std::vector<DiracSpinor> &excited,
                   const Angular::SixJTable &SixJ, Denominators denominators);
 
double S_Sigma2_c1(int k, const DiracSpinor &v, const DiracSpinor &w,
                   const DiracSpinor &x, const DiracSpinor &y,
                   const Coulomb::QkTable &qk,
                   const std::vector<DiracSpinor> &core,
                   const std::vector<DiracSpinor> &excited,
                   const Angular::SixJTable &SixJ, Denominators denominators);
 
double S_Sigma2_c2(int k, const DiracSpinor &v, const DiracSpinor &w,
                   const DiracSpinor &x, const DiracSpinor &y,
                   const Coulomb::QkTable &qk,
                   const std::vector<DiracSpinor> &core,
                   const std::vector<DiracSpinor> &excited,
                   const Angular::SixJTable &SixJ, Denominators denominators);
 
double S_Sigma2_d(int k, const DiracSpinor &v, const DiracSpinor &w,
                  const DiracSpinor &x, const DiracSpinor &y,
                  const Coulomb::QkTable &qk,
                  const std::vector<DiracSpinor> &core,
                  const std::vector<DiracSpinor> &excited,
                  const Angular::SixJTable &SixJ, Denominators denominators);
} // namespace InternalSigma
 
} // namespace MBPT
 
//==============================================================================
#include "Sigma2.ipp"