Green functions in the renormalized many-body perturbation theory

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68378271%3A_____%2F21%3A00553891" target="_blank" >RIV/68378271:_____/21:00553891 - isvavai.cz</a>

Výsledek na webu

<a href="https://www.cond-mat.de/events/correl21/manuscripts/correl21.pdf" target="_blank" >https://www.cond-mat.de/events/correl21/manuscripts/correl21.pdf</a>

DOI - Digital Object Identifier

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Jazyk výsledku

angličtina

Název v původním jazyce

Green functions in the renormalized many-body perturbation theory

Popis výsledku v původním jazyce

I review how renormalizations are introduced in the quantum many-body perturbation theory. The one-particle renormalizations are discussed within the Baym-Kadanoff construction. We point to an inherent dichotomy of the Baym-Kadanoff approach in the relation between one and two-particle Green functions. They are the Schwinger-Dyson equation and the Ward identity that cannot be satisfied simultaneously in any approximate theory. I further introduce the two-particle approach with two-particle renormalizations that offers a way to reconcile the the two relations. Finally, I discuss a static mean-field-like approximation with a renormalized effective interaction determined self-consistently in the reduced parquet equations that leads to a qualitatively correct description of strong electron correlations in impurity and lattice models.

Název v anglickém jazyce

Green functions in the renormalized many-body perturbation theory

Popis výsledku anglicky

I review how renormalizations are introduced in the quantum many-body perturbation theory. The one-particle renormalizations are discussed within the Baym-Kadanoff construction. We point to an inherent dichotomy of the Baym-Kadanoff approach in the relation between one and two-particle Green functions. They are the Schwinger-Dyson equation and the Ward identity that cannot be satisfied simultaneously in any approximate theory. I further introduce the two-particle approach with two-particle renormalizations that offers a way to reconcile the the two relations. Finally, I discuss a static mean-field-like approximation with a renormalized effective interaction determined self-consistently in the reduced parquet equations that leads to a qualitatively correct description of strong electron correlations in impurity and lattice models.

Druh

C - Kapitola v odborné knize

CEP obor

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OECD FORD obor

10302 - Condensed matter physics (including formerly solid state physics, supercond.)

Projekt

<a href="/cs/project/GA19-13525S" target="_blank" >GA19-13525S: Kvantová koherence v systémech s elektronovými korelacemi: supravodivost a magnetismus v nanosoučástkách a objemových materiálech</a><br>

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2021

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název knihy nebo sborníku

Simulating Correlations with Computers Modeling and Simulation

ISBN

978-3-95806-529-1

Počet stran výsledku

29

Strana od-do

"7.2"-"7.29"

Počet stran knihy

390

Název nakladatele

Verlag des Forschungszentrum Jülich

Místo vydání

Jülich

Kód UT WoS kapitoly

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