Tiling with triangles: parquet and GWγ methods unified

The parquet formalism and Hedin's GW gamma approach are unified into a single theory of vertex corrections, corresponding to an exact reformulation of the parquet equations in terms of boson exchange. The method has no drawbacks compared to previous parquet solvers but has the significant advantage that the vertex functions decay quickly with frequencies and with respect to distances in real space. These properties coincide with the respective separation of the length and energy scales of the two-particle correlations into long/short-ranged and high/low-energetic.

Automated summary

The formalism unifies parquet and Hedin's GW gamma approach into a single theory of vertex corrections, reformulating parquet equations in terms of boson exchange. The method has no drawbacks compared to previous parquet solvers and the significant advantage of vertex functions decaying quickly with frequencies and distances in real space, coinciding with the separation of length and energy scales of two-particle correlations into long/short-ranged and high/low-energetic.