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An application of an effective numerical algorithm for solving eigenvalue problems which arise in modelling electronic properties of quantum disordered systems is considered. We study the electron states at the localization-delocalization…

Computational Physics · Physics 2009-11-06 Isa Kh. Zharekeshev , Bernhard Kramer

The Lanczos algorithm is evaluated for solving the time-independent as well as the time-dependent Dirac equation with arbitrary electromagnetic fields. We demonstrate that the Lanczos algorithm can yield very precise eigenenergies and…

Computational Physics · Physics 2015-01-05 Randolf Beerwerth , Heiko Bauke

The computational cost of quantum Monte Carlo (QMC) calculations of realistic periodic systems depends strongly on the method of storing and evaluating the many-particle wave function. Previous work [A. J. Williamson et al., Phys. Rev.…

Computational Physics · Physics 2014-10-31 William D. Parker , C. J. Umrigar , Dario Alfè , Richard G. Hennig , John W. Wilkins

Several strategies are described and analyzed to speed-up gradient-type methods when applied to the minimization of strictly convex quadratics and strictly convex functions. The proposed techniques focus on relaxing the traditional optimal…

Numerical Analysis · Mathematics 2026-01-19 Jean-Paul Chehab , Gaspard Kemlin , Marcos Raydan , Yousef Saad

We present GW calculations of molecules, ordered and disordered solids and interfaces, which employ an efficient contour deformation technique for frequency integration, and do not require the explicit evaluation of virtual electronic…

Materials Science · Physics 2015-01-14 Marco Govoni , Giulia Galli

Reliable adaptive beamforming is critical for large microphone arrays operating in highly dynamic acoustic environments. In scenarios characterized by fast-moving talkers and interferers, the available sample support for estimating the…

Signal Processing · Electrical Eng. & Systems 2026-05-13 Manan Mittal , Ryan M. Corey , John R. Buck , Andrew C. Singer

We begin by addressing the time-domain full-waveform inversion using the adjoint method. Next, we derive the scaled boundary semi-weak form of the scalar wave equation in heterogeneous media through the Galerkin method. Unlike conventional…

Numerical Analysis · Mathematics 2025-01-14 Alireza Daneshyar , Stefan Kollmannsberger

A new inverse iteration algorithm that can be used to compute all the eigenvectors of a real symmetric tri-diagonal matrix on parallel computers is developed. The modified Gram-Schmidt orthogonalization is used in the classical inverse…

Numerical Analysis · Computer Science 2012-09-11 Hiroyuki Ishigami , Kinji Kimura , Yoshimasa Nakamura

The optimization of cooperative beamforming vectors in cell-free massive MIMO (mMIMO) systems is presented where multi-antenna access points (APs) support downlink data transmission of multiple users. Albeit the successes of the weighted…

Signal Processing · Electrical Eng. & Systems 2024-08-05 Wonsik Yoo , Daesung Yu , Hoon Lee , Seok-Hwan Park

Objectives involving bilinear forms $u^\top f(A(\theta))v$ for Hermitian $A$ arise widely in scientific computing and probabilistic machine learning. For large matrices, Lanczos efficiently approximates these quantities, but differentiating…

Numerical Analysis · Mathematics 2026-05-14 Navjot Singh , Kipton Barros , Xiaoye Sherry Li

We report an attempt to calculate energy eigenvalues of large quantum systems by the diagonalization of an effectively truncated Hamiltonian matrix. For this purpose we employ a specific way to systematically make a set of orthogonal states…

Strongly Correlated Electrons · Physics 2009-10-31 T. Munehisa , Y. Munehisa

Performing analog computations with metastructures is an emerging wave-based paradigm for solving mathematical problems. For such devices, one major challenge is their reconfigurability, especially without the need for a priori mathematical…

Applied Physics · Physics 2022-06-07 Dimitrios Tzarouchis , Mario Junior Mencagli , Brian Edwards , Nader Engheta

This work introduces a simple and efficient linesearch method for composite minimization that accelerates proximal-gradient iterations with fast Newton-type directions. Our algorithm is based on simple operations and only requires the…

Optimization and Control · Mathematics 2026-04-17 Alexander Bodard , Pieter Pas , Andreas Themelis , Panagiotis Patrinos

The block Lanczos algorithm proposed by Peter Montgomery is an efficient means to tackle the sparse linear algebra problem which arises in the context of the number field sieve factoring algorithm and its predecessors. We present here a…

Cryptography and Security · Computer Science 2016-04-11 Emmanuel Thomé

Millimeter-wave (MMW) multiple-input multiple-output synthetic aperture radar (MIMO-SAR) system is a technology that can achieve high resolution, high frame rate, and all-weather imaging and has received extensive attention in the…

Signal Processing · Electrical Eng. & Systems 2024-11-25 Xu Chen , Guangsheng Yu , Zhian Yuan , Hao Wu , Yilin Jiang , Ying Wang , Bin Deng , Limin Guo

The Lagrange multiplier method has proven highly effective for mitigating the ill-conditioning of full waveform inversion (FWI), enabling robust and computationally efficient algorithms that converge to accurate velocity models even from…

Geophysics · Physics 2025-10-01 Ali Gholami , Kamal Aghazade , Akshay Vishwakarma

We introduce a highly-parallelizable architecture for estimating parameters of compact binary coalescence using gravitational-wave data and waveform models. Using a spherical harmonic mode decomposition, the waveform is expressed as a sum…

General Relativity and Quantum Cosmology · Physics 2015-08-06 C. Pankow , P. Brady , E. Ochsner , R. O'Shaughnessy

The computation and memory costs of large language models kept increasing over last decade, which reached over the scale of 1T parameters. To address the challenges from the large scale models, model compression techniques such as low-rank…

Hardware Architecture · Computer Science 2025-10-16 Faraz Tahmasebi , Michael Pelluer , Hyoukjun Kwon

We present a systematic study of the performance of numerical pseudo-atomic orbital basis sets in the calculation of dielectric matrices of extended systems using the self-consistent Sternheimer approach of [F. Giustino et al., Phys. Rev. B…

Materials Science · Physics 2015-06-04 Hannes Hübener , Miguel A. Pérez-Osorio , Pablo Ordejón , Feliciano Giustino

A deflated and restarted Lanczos algorithm to solve hermitian linear systems, and at the same time compute eigenvalues and eigenvectors for application to multiple right-hand sides, is described. For the first right-hand side, eigenvectors…

High Energy Physics - Lattice · Physics 2010-01-21 Abdou M. Abdel-Rehim , Ronald B. Morgan , Dywayne Nicely , Walter Wilcox