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arXiv · 2009.12868

Tiling with triangles: parquet and $GW\gamma$ methods unified

Friedrich Krien·Anna Kauch·Karsten Held
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Abstract

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.

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Friedrich Krien, Anna Kauch, Karsten Held. 2020-09-27. Tiling with triangles: parquet and $GW\gamma$ methods unified. https://doi.org/10.1103/physrevresearch.3.013149

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