product¶
Synopsis:
template<Channel_t CH>
triqs_tprf::g2_iw_t product (triqs_tprf::g2_iw_cvt A, triqs_tprf::g2_iw_cvt B)
Two-particle response-function product \(A * B\)
Note
Assign to gf (g2_iw_t) yields move operation while assigning to gf_view (g2_iw_vt) causes extra copy operation
Template parameters¶
- CH: selects the two-particle channel
Parameters¶
- A: two-particle response function \(A \equiv A_{abcd}(\omega, \nu, \nu')\)
- B: two-particle response function \(B \equiv A_{abcd}(\omega, \nu, \nu')\)
Return value¶
\((A * B)\) in the given channel
Documentation¶
The two-particle response functions \(A \equiv A_{abcd}(\omega, \nu, \nu')\) and \(B \equiv B_{abcd}(\omega, \nu, \nu')\) are cast to matrix form and their product is computed
(1)¶\[(A * B)_{\{\nu\alpha\beta\}, \{\nu'\gamma\delta\}}(\omega) = \sum_{\bar{\nu}ab} A_{\{\nu\alpha\beta\}, \{\bar{\nu}ab\}}(\omega) B_{\{\bar{\nu}ab\}, \{\nu'\gamma\delta\}}(\omega)\]where the mapping of target-space indices \(\{a, b, c, d \}\) to \(\{\alpha, \beta\}, \{\gamma, \delta\}\) is channel dependent.
Storage is allocated and the product is returned by value.