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By combining Hartree-Fock with a neural-network-supported quantum-cluster solver proposed recently in the context of solid-state lattice models, we formulate a scheme for selective neural-network configuration interaction (NNCI)…

We propose a framework for suboptimal model predictive control (MPC) based on the interconnection of monotone dynamical systems, such as port-Hamiltonian systems. In contrast to classical MPC formulations, where the optimizer is treated as…

Optimization and Control · Mathematics 2026-05-25 Till Preuster , Hannes Gernandt , Manuel Schaller

We analyzed the Hartree-Fock approximation for an electron system. The interaction between particles is modeled by a non-Coulombian potential. We analyzed both the three-dimensional and two-dimensional systems. We obtained accurate…

Quantum Gases · Physics 2024-08-28 Vlad-Mihai Ene , Ilinca Lianu , Ioan Grosu

We derive and implement symmetry-projected Hartree-Fock-Bogoliubov (HFB) equations and apply them to the molecular electronic structure problem. All symmetries (particle number, spin, spatial, and complex conjugation) are deliberately…

Strongly Correlated Electrons · Physics 2012-02-15 Gustavo E. Scuseria , Carlos A. Jimenez-Hoyos , Thomas M. Henderson , Kousik Samanta , Jason K. Ellis

Tailored coupled cluster theory represents a computationally inexpensive way to describe static and dynamical electron correlation effects. In this work, we scrutinize the performance of various tailored coupled cluster methods externally…

Chemical Physics · Physics 2021-03-24 Aleksandra Leszczyk , Mihály Máté , Örs Legeza , Katharina Boguslawski

Compositional Explanations is a method for identifying logical formulas of concepts that approximate the neurons' behavior. However, these explanations are linked to the small spectrum of neuron activations (i.e., the highest ones) used to…

Machine Learning · Computer Science 2023-10-31 Biagio La Rosa , Leilani H. Gilpin , Roberto Capobianco

Coupled cluster theory produced arguably the most widely used high-accuracy computational quantum chemistry methods. Despite the approach's overall great computational success, its mathematical understanding is so far limited to results…

Algebraic Geometry · Mathematics 2024-03-29 Fabian M. Faulstich , Mathias Oster

Cluster analysis relates to the task of assigning objects into groups which ideally present some desirable characteristics. When a cluster structure is confined to a subset of the feature space, traditional clustering techniques face…

Machine Learning · Statistics 2026-04-14 Efthymios Costa , Ioanna Papatsouma , Angelos Markos

Unitary coupled cluster (UCC), originally developed as a variational alternative to the popular traditional coupled cluster method, has seen a resurgence as a functional form for use on quantum computers. However, the number of excitors…

Chemical Physics · Physics 2021-01-07 Maria-Andreea Filip , Alex J. W. Thom

When the number of strongly correlated electrons becomes larger, the single-reference coupled-cluster (CC) CCSD, CCSDT, etc. hierarchy displays an erratic behavior, while traditional multi-reference approaches may no longer be applicable…

Chemical Physics · Physics 2025-12-12 Ilias Magoulas , Jun Shen , Piotr Piecuch

The main issue of this work consists in extracting one or several finite values for the sum of series involved in perturbation theories. It is supposed to work for all cases in which two physical parameters are involved, and makes thorough…

Mathematical Physics · Physics 2007-05-23 Benoit Bellet

We propose a multireference linearized coupled cluster theory using matrix product states (MPS-LCC) which provides remarkably accurate ground-state energies, at a computational cost that has the same scaling as multireference configuration…

Chemical Physics · Physics 2015-09-02 Sandeep Sharma , Ali Alavi

This paper studies a factor modeling-based approach for clustering high-dimensional data generated from a mixture of strongly correlated variables. Statistical modeling with correlated structures pervades modern applications in economics,…

Statistics Theory · Mathematics 2024-08-23 Shange Tang , Soham Jana , Jianqing Fan

The coherent potential approximation, CPA, is a useful tool to treat systems with disorder. Cluster theories have been proposed to go beyond the translation invariant single-site CPA approximation and include some short range correlations.…

Condensed Matter · Physics 2009-10-31 C. I. Ventura , R. A. Barrio , .

Correlations in the nuclear wave-function beyond the mean-field or Hartree-Fock approximation are very important to describe basic properties of nuclear structure. Various approaches to account for such correlations are described and…

Nuclear Theory · Physics 2009-11-06 H. Müther , A. Polls

This paper explores the problem of clustering ensemble, which aims to combine multiple base clusterings to produce better performance than that of the individual one. The existing clustering ensemble methods generally construct a…

Machine Learning · Computer Science 2020-12-17 Yuheng Jia , Hui Liu , Junhui Hou , Qingfu Zhang

Basis set convergence of the Hartree-Fock and the correlation energy is examined for the hydrogen bonded infinite bent chains (HF)_infinity and (HCl)_infinity. We employ series of correlation consistent basis sets up to quintuple zeta…

Other Condensed Matter · Physics 2007-05-23 Christian Buth , Beate Paulus

We describe a coupled cluster framework for coupled systems of electrons and phonons. Neutral and charged excitations are accessed via the equation-of-motion version of the theory. Benchmarks on the Hubbard-Holstein model allow us to assess…

Materials Science · Physics 2021-02-03 Alec F. White , Yang Gao , Austin J. Minnich , Garnet Kin-Lic Chan

Recently, we developed a mean-field-type framework which treats the correlation induced by the tensor force. To exploit the tensor correlation we introduce single-particle states with the parity and charge mixing. To make a total wave…

Nuclear Theory · Physics 2008-11-26 Satoru Sugimoto , Kiyomi Ikeda , Hiroshi Toki

Real-time coupled cluster (CC) methods have several advantages over their frequency-domain counterparts, namely, response and equation of motion CC theories. Broadband spectra, strong fields, and pulse manipulation allow for the simulation…

Chemical Physics · Physics 2023-08-04 Benjamin G. Peyton , Zhe Wang , T. Daniel Crawford