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Ground state energy estimation in physical, chemical, and materials sciences is one of the most promising applications of quantum computing. In this work, we introduce a new hybrid approach that finds the eigenenergies by collecting…

Starting from a comparison of some established numerical algorithms for the computation of the eigenvalues (discrete or solitonic spectrum) of the non-Hermitian version of the Zakharov-Shabat spectral problem, this article delivers new…

Numerical Analysis · Mathematics 2018-09-11 A. Vasylchenkova , J. E. Prilepsky , D. Shepelsky , A. Chattopadhyay

We examine and compare several iterative methods for solving large-scale eigenvalue problems arising from nuclear structure calculations. In particular, we discuss the possibility of using block Lanczos method, a Chebyshev filtering based…

Numerical Analysis · Mathematics 2023-05-26 Abdullah Alperen , Metin Aktulga , Pieter Maris , Chao Yang

The variational quantum eigensolver (VQE) is a method that uses a hybrid quantum-classical computational approach to find eigenvalues and eigenvalues of a Hamiltonian. VQE has been proposed as an alternative to fully quantum algorithms such…

Quantum Physics · Physics 2021-09-01 Dmitry A. Fedorov , Bo Peng , Niranjan Govind , Yuri Alexeev

The linear FEAST algorithm is a method for solving linear eigenvalue problems. It uses complex contour integration to calculate the eigenvectors whose eigenvalues that are located inside some user-defined region in the complex plane. This…

Computational Physics · Physics 2018-01-31 Brendan Gavin , Agnieszka Międlar , Eric Polizzi

Finite element analysis (FEA) has been widely used to generate simulations of complex and nonlinear systems. Despite its strength and accuracy, the limitations of FEA can be summarized into two aspects: a) running high-fidelity FEA often…

Machine Learning · Computer Science 2020-12-15 Yinan Wang , Kaiwen Wang , Wenjun Cai , Xiaowei Yue

This paper is to introduce a type of full multigrid method for the nonlinear eigenvalue problem. The main idea is to transform the solution of nonlinear eigenvalue problem into a series of solutions of the corresponding linear boundary…

Numerical Analysis · Mathematics 2016-11-03 Shanghui Jia , Hehu Xie , Manting Xie , Fei Xu

Although electrostatics can be incorporated into machine-learned interatomic potentials, existing approaches are computationally very demanding, limiting large-scale, long-time simulations of electrostatics-driven phenomena such as…

In this paper, a full (nested) multigrid scheme is proposed to solve eigenvalue problems. The idea here is to use the multilevel correction method to transform the solution of eigenvalue problem to a series of solutions of the corresponding…

Numerical Analysis · Mathematics 2015-06-23 Hehu Xie

An artificial intelligence-augmented Streamline Upwind/Petrov-Galerkin finite element scheme (AiStab-FEM) is proposed for solving singularly perturbed partial differential equations. In particular, an artificial neural network framework is…

Analysis of PDEs · Mathematics 2022-11-28 Sangeeta Yadav , Sashikumaar Ganesan

We investigated the detailed plasma condition of the North Polar Spur (NPS)/Loop I using archival $Suzaku$ data. In previous research collisional ionization equilibrium (CIE) have been assumed for X-ray plasma state, but we also assume…

High Energy Astrophysical Phenomena · Physics 2022-03-03 Marino Yamamoto , Jun Kataoka , Yoshiaki Sofue

In this paper we propose a new formulation of the Fourier Modal Method based on an alternative treatment of interface conditions allowing us to overcome the effect of the Gibbs phenomenon. Explicit consideration of the interface conditions…

Optics · Physics 2022-12-15 Sergey Spiridonov , Alexey A. Shcherbakov

This paper presents a new boundary integral equation (BIE) method for simulating particulate and multiphase flows through periodic channels of arbitrary smooth shape in two dimensions. The authors consider a particular system---multiple…

Numerical Analysis · Mathematics 2015-10-20 Gary Marple , Alex Barnett , Adrianna Gillman , Shravan Veerapaneni

Version 11 of the CHIANTI database and software package is presented. Advanced ionization equilibrium models have been added for low charge states of seven elements (C, N, O, Ne, Mg, Si and S), and represent a significant improvement…

Solar and Stellar Astrophysics · Physics 2024-03-26 R. P. Dufresne , G. Del Zanna , P. R. Young , K. P. Dere , E. Deliporanidou , W. T. Barnes , E. Landi

This paper presents a novel methodology for fast simulation and analysis of transient heat transfer. The proposed methodology is suitable for real-time applications owing to (i) establishing the solution method from the viewpoint of…

Computational Engineering, Finance, and Science · Computer Science 2021-12-30 Jinao Zhang , Sunita Chauhan

The classical-quantum hybrid Variational Quantum Eigensolver algorithm is the most widely used approach in the Noisy Intermediate Scale Quantum era to obtain ground state energies of atomic and molecular systems. In this work, we extend the…

Atomic Physics · Physics 2021-09-28 Rene Villela , V. S. Prasannaa , B. P. Das

Low-temperature plasmas often present non-equilibrium ion distribution functions due to the collisions with the background gas and the presence of strong electric fields. This non-equilibrium is beyond classical fluid models, often…

Plasma Physics · Physics 2025-10-31 Anatole Berger , Thierry Magin , Anne Bourdon , Alejandro Alvarez Laguna

We resume the recent successes of the grid-based tensor numerical methods and discuss their prospects in real-space electronic structure calculations. These methods, based on the low-rank representation of the multidimensional functions and…

Numerical Analysis · Mathematics 2016-01-20 Venera Khoromskaia , Boris N. Khoromskij

Our aim is to determine the dominant processes and timescales for the ionisation equilibrium of calcium under solar chromospheric conditions. The study is based on numerical simulations with the RADYN code, which includes hydrodynamics,…

Solar and Stellar Astrophysics · Physics 2015-05-27 Sven Wedemeyer-Böhm , Mats Carlsson

This paper proposes a novel first-order and a novel second-order fully discrete virtual element schemes based on the scalar auxiliary variable method for the three dimensional inductionless magnetohydrodynamics problem. The backward Eular…

Analysis of PDEs · Mathematics 2024-12-13 Xianghai Zhou , Haiyan Su
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