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Related papers: The many-body Green function of degenerate systems

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We introduce Neural Green's Function, a neural solution operator for linear partial differential equations (PDEs) whose differential operators admit eigendecompositions. Inspired by Green's functions, the solution operators of linear PDEs…

Machine Learning · Computer Science 2025-11-05 Seungwoo Yoo , Kyeongmin Yeo , Jisung Hwang , Minhyuk Sung

Many-body theory is largely based on self-consistent equations that are constructed in terms of the physical quantity of interest itself, for example the density. Therefore, the calculation of important properties such as total energies or…

Materials Science · Physics 2015-10-28 Adrian Stan , Pina Romaniello , Santiago Rigamonti , Lucia Reining , J. A. Berger

Pad\'e approximants to the many-body Green's function can be built by rearranging terms of its perturbative expansion. The hypothesis that the best use of a finite number of terms of such an expansion is given by the subclass of diagonal…

Strongly Correlated Electrons · Physics 2019-03-06 Walter Tarantino , Stefano Di Sabatino

Many-body quantum systems in nonequilibrium remain one of the frontiers of many-body physics. While there has been significant advances in describing the short-time evolution of these systems using a variety of different numerical…

Quantum Physics · Physics 2021-01-05 Herbert F. Fotso , Eric Dohner , Alexander Kemper , James K. Freericks

We present a quantum-classical hybrid implementation of the Liouvillian recursion method to compute many-body Green's functions using a quantum computer. From an approximate ground state preparation circuit, this algorithm produces the…

In using the spectral theorem of many-body Green's function theory in order to relate correlations to commutator Green's functions, it is necessary in the standard procedure to consider the anti-commutator Green's functions as well whenever…

Statistical Mechanics · Physics 2009-11-10 P. Fröbrich , P. J. Kuntz

We present the fundamental techniques and working equations of many-body Green's function theory for calculating ground state properties and the spectral strength. Green's function methods closely relate to other polynomial scaling…

Nuclear Theory · Physics 2017-06-28 Carlo Barbieri , Arianna Carbone

In non-equilibrium Green's function calculations the use of the Generalized Kadanoff-Baym Ansatz (GKBA) allows for a simple approximate reconstruction of the two-time Green's function from its time-diagonal value. With this a drastic…

Strongly Correlated Electrons · Physics 2013-09-19 S. Hermanns , K. Balzer , M. Bonitz

Nonequilibrium Green's function methods allow for an intrinsically consistent description of the evolution of quantal many-body body systems, with inclusion of different types of correlations. In this paper, we focus on the practical…

Nuclear Theory · Physics 2011-04-20 Arnau Rios , Brent Barker , Mark Buchler , Pawel Danielewicz

Despite its centrality in the mathematical structure of perturbative many-body theory, the total Green's function for the many-body time-dependent Schrodinger equation has been ignored for decades, superseded by single-particle Green's…

Strongly Correlated Electrons · Physics 2016-02-26 David Roberts

We present an ongoing development of an existing code for calculating ground-state, steady-state, and transient properties of many-particle systems. The development involves the addition of the full four-index two electron integrals, which…

Mesoscale and Nanoscale Physics · Physics 2016-05-04 Richard A. Lynn , Robert van Leeuwen

We present a concise, but systematic, review of the ergodicity issue in strongly correlated systems. After giving a brief historical overview, we analyze the issue within the Green's function formalism by means of the equations of motion…

Strongly Correlated Electrons · Physics 2007-07-27 Adolfo Avella , Ferdinando Mancini , Evgeny Plekhanov

Non-equilibrium Green's functions provide an efficient way to describe the evolution of the energy-momentum tensor during the early time pre-equilibrium stage of high-energy heavy ion collisions. Besides their practical relevance they also…

High Energy Physics - Phenomenology · Physics 2020-09-09 Syo Kamata , Mauricio Martinez , Philip Plaschke , Stephan Ochsenfeld , S. Schlichting

Many-body Green's functions encode all the properties and excitations of interacting electrons. While these are challenging to be evaluated accurately on a classical computer, recent efforts have been directed towards finding quantum…

Calculations of excited states in Green's function formalism often invoke the diagonal approximation, in which the quasiparticle states are taken from a mean-field calculation. Here, we extend the stochastic approaches applied in the…

Computational Physics · Physics 2023-09-28 Annabelle Canestraight , Xiaohe Lei , Khaled Ibrahim , Vojtech Vlcek

In this paper some new physical notations are given for the Green's functions and equations of motion (EOM) in many body physics with the concept of quasiparticles. It shows how the many body correlations existing in many body systems can…

Strongly Correlated Electrons · Physics 2013-02-20 Qingguo Feng

We construct Green's functions for divergence form, second order parabolic systems in non-smooth time-varying domains whose boundaries are locally represented as graph of functions that are Lipschitz continuous in the spatial variables and…

Analysis of PDEs · Mathematics 2014-09-25 Hongjie Dong , Seick Kim

We provide a systematic approach to compute different kinds of non-equilibrium Green's functions for open quantum systems which are essentially two-point correlation functions in time. We reveal that the definition of Green's functions…

Statistical Mechanics · Physics 2023-09-08 Katha Ganguly , Bijay Kumar Agarwalla

Strongly interacting matter such as nuclear or quark matter leads to few-body bound states and correlations of the constituents. As a consequence quantum chromodynamics has a rich phase structure with spontaneous symmetry breaking,…

Nuclear Theory · Physics 2009-11-10 M. Beyer , S. Mattiello , S. Strauss , T. Frederico , H. J. Weber , P. Schuck , S. A. Sofianos

A local-orbital based ab initio approach to obtain the Green function for large heterogeneous systems is developed. First a Green function formalism is introduced based on exact diagonalization. Then the self energy is constructed from an…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 M. Albrecht , A. Schnurpfeil , G. Cuniberti