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Related papers: Memory truncated Kadanoff-Baym equations

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Potential non-relativistic Quantum Electrodynamics and the Keldysh-Schwinger formalism is used to derive Kadanoff-Baym-like equations for two-body field correlators. These cover the out-off-equilibrium dynamics and spectrum of heavy…

High Energy Physics - Theory · Physics 2021-10-13 Tobias Binder

The time evolution of optically excited carriers in semiconductor quantum wells and quantum dots is analyzed for their interaction with LO-phonons. Both the full two-time Green's function formalism and the one-time approximation provided by…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 Paul Gartner , Jan Seebeck , Frank Jahnke

We propose a description of nonequilibrium systems via a simple protocol that combines exchange-correlation potentials from density functional theory with self-energies of many-body perturbation theory. The approach, aimed to avoid double…

Strongly Correlated Electrons · Physics 2016-06-15 M. Hopjan , D. Karlsson , S. Ydman , C. Verdozzi , C. -O. Almbladh

The generalized Kadanoff-Baym ansatz (GKBA) offers a computationally inexpensive approach to simulate out-of-equilibrium quantum systems within the framework of nonequilibrium Green's functions. For finite systems the limitation of…

Mesoscale and Nanoscale Physics · Physics 2021-03-02 Riku Tuovinen , Robert van Leeuwen , Enrico Perfetto , Gianluca Stefanucci

We study the Hubbard model using the Cellular Dynamical Mean-Field Theory (CDMFT) with quantum Monte Carlo (QMC) simulations. We present the algorithmic details of CDMFT with the Hirsch-Fye QMC method for the solution of the…

Strongly Correlated Electrons · Physics 2009-11-11 B. Kyung , G. Kotliar , A. -M. S. Tremblay

We develop a time dependent second order Green's function theory (GF2) for calculating neutral excited states in molecules. The equation of motion for the lesser Green's function (GF) is derived within the adiabatic approximation to the…

Chemical Physics · Physics 2022-01-19 Wenjie Dou , Joonho Lee , David R. Reichman , Roi Baer , Eran Rabani

Harnessing the quantum computation power of the present noisy-intermediate-size-quantum devices has received tremendous interest in the last few years. Here we study the learning power of a one-dimensional long-range randomly-coupled…

Quantum Physics · Physics 2022-05-03 Wei Xia , Jie Zou , Xingze Qiu , Xiaopeng Li

The present paper proposes an adaptive biasing potential for the computation of free energy landscapes. It is motivated by statistical learning arguments and unifies the tasks of biasing the molecular dynamics to escape free energy wells…

Mathematical Physics · Physics 2018-03-05 I. Bilionis , P. S. Koutsourelakis

In this study we introduce a novel energy functional for long-sequence memory, building upon the framework of dense Hopfield networks which achieves exponential storage capacity through higher-order interactions. Building upon earlier work…

Machine Learning · Computer Science 2025-07-03 Ahmed Farooq

It is shown that the non-equilibrium self-energy of an interacting lattice-fermion model has a unique Lehmann representation. Based on the construction of a suitable non-interacting effective medium, we provide an explicit and numerically…

Strongly Correlated Electrons · Physics 2015-12-22 Christian Gramsch , Michael Potthoff

Erasure of the binary memory, 0 or 1, is an essential step for digital computation involving irreversible logic operations. The erasure of a bit of a classical bit of memory is accompanied by the evolution of a minimum amount of heat set by…

Statistical Mechanics · Physics 2026-04-14 Vipul Rai , Moupriya Das

The temporal evolution of a quantum system can be characterized by quantum process tomography, a complex task that consumes a number of physical resources scaling exponentially with the number of subsystems. An alternative approach to the…

We introduce the notion of non-Abelian tensors, and use them to construct a general non-Abelian time evolving block decimation (NA-TEBD) scheme that uses an arbitrary number of Abelian and non-Abelian symmetries. Our approach increases the…

Strongly Correlated Electrons · Physics 2020-10-14 Miklós Antal Werner , Cătălin Paşcu Moca , Örs Legeza , Gergely Zaránd

Many hardware proposals have aimed to accelerate inference in AI workloads. Less attention has been paid to hardware acceleration of training, despite the enormous societal impact of rapid training of AI models. Physics-based computers,…

Precise algorithms capable of providing controlled solutions in the presence of strong interactions are transforming the landscape of quantum many-body physics. Particularly exciting breakthroughs are enabling the computation of non-zero…

Stochastic modelling is an essential component of the quantitative sciences, with hidden Markov models (HMMs) often playing a central role. Concurrently, the rise of quantum technologies promises a host of advantages in computational…

Quantum Physics · Physics 2021-06-22 Thomas J. Elliott

Hybrid quantum-classical algorithms have been proposed to circumvent noise limitations in quantum computers. Such algorithms delegate only a calculation of the expectation value to the quantum computer. Among them, the Variational Quantum…

Strongly Correlated Electrons · Physics 2022-11-02 Baptiste Anselme Martin , Pascal Simon , Marko J. Rančić

Nonequilibrium Green's functions represent underutilized means of studying the time evolution of quantum many-body systems. In view of a rising computer power, an effort is underway to apply the Green's functions formalism to the dynamics…

Nuclear Theory · Physics 2008-11-26 Arnau Rios , Pawel Danielewicz

We show that the nonperturbative transport equations, the so called `Kadanoff-Baym equations', within the non-equilibrium real time Green's function description can be be understood as the ensemble average over stochastic equations of…

High Energy Physics - Phenomenology · Physics 2007-05-23 Carsten Greiner , Stefan Leupold

The encoding of lattice gauge theories onto quantum computers requires a discretization of the gauge field's Hilbert space on each link, which presents errors with respect to the Kogut--Susskind limit. In the electric basis, Hilbert space…