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Related papers: Filtered Rayleigh-Ritz is all you need

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LSQR and its mathematically equivalent CGLS have been popularly used over the decades for large-scale linear discrete ill-posed problems, where the iteration number $k$ plays the role of the regularization parameter. It has been long known…

Numerical Analysis · Mathematics 2020-03-20 Zhongxiao Jia

Random Matrix Theory (RMT) has successfully modeled diverse systems, from energy levels of heavy nuclei to zeros of $L$-functions; this correspondence has allowed RMT to successfully predict many number theoretic behaviors. However there…

We present randUBV, a randomized algorithm for matrix sketching based on the block Lanzcos bidiagonalization process. Given a matrix $\bf{A}$, it produces a low-rank approximation of the form ${\bf UBV}^T$, where $\bf{U}$ and $\bf{V}$ have…

Numerical Analysis · Mathematics 2021-02-09 Eric Hallman

We derive, similar to Lau and Riha, a matrix formulation of a general best approximation theorem of Singer for the special case of spectral approximations of a given matrix from a given subspace. Using our matrix formulation we describe the…

Numerical Analysis · Mathematics 2025-06-12 Vance Faber , Jörg Liesen , Petr Tichý

We present algorithmic improvements for fast and memory-efficient use of discrete spatial symmetries in Exact Diagonalization computations of quantum many-body systems. These techniques allow us to work flexibly in the reduced basis of…

Strongly Correlated Electrons · Physics 2018-10-05 Alexander Wietek , Andreas M. Läuchli

The power method and block Lanczos method are popular numerical algorithms for computing the truncated singular value decomposition (SVD) and eigenvalue decomposition problems. Especially in the literature of randomized numerical linear…

Numerical Analysis · Computer Science 2015-12-21 Shusen Wang , Zhihua Zhang , Tong Zhang

We introduce a new implementation of time-dependent density-functional theory which allows the \emph{entire} spectrum of a molecule or extended system to be computed with a numerical effort comparable to that of a \emph{single} standard…

Materials Science · Physics 2009-11-13 Dario Rocca , Ralph Gebauer , Yousef Saad , Stefano Baroni

We analyze the FEAST method for computing selected eigenvalues and eigenvectors of large sparse matrix pencils. After establishing the close connection between FEAST and the well-known Rayleigh-Ritz method, we identify several critical…

Numerical Analysis · Computer Science 2012-04-10 Lukas Krämer , Edoardo Di Napoli , Martin Galgon , Bruno Lang , Paolo Bientinesi

Preconditioned gradient iterations for very large eigenvalue problems are efficient solvers with growing popularity. However, only for the simplest preconditioned eigensolver, namely the preconditioned gradient iteration (or preconditioned…

Numerical Analysis · Mathematics 2011-08-12 Klaus Neymeyr

Random matrix theory is a powerful way to describe universal correlations of eigenvalues of complex systems. It also may serve as a schematic model for disorder in quantum systems. In this review, we discuss both types of applications of…

High Energy Physics - Phenomenology · Physics 2009-10-31 J. J. M. Verbaarschot , T. Wettig

We present a novel Krylov subspace method for approximating $L_f(A, E) \vc{b}$, the matrix-vector product of the Fr\'echet derivative $L_f(A, E)$ of a large-scale matrix function $f(A)$ in direction $E$, a task that arises naturally in the…

Numerical Analysis · Mathematics 2026-01-30 Daniel Kressner , Peter Oehme

Quadratic forms of Hermitian matrix resolvents involve the solutions of shifted linear systems. Efficient iterative solutions use the shift-invariance property of Krylov subspaces The Hermitian Lanczos method reduces a given vector and…

Numerical Analysis · Mathematics 2020-10-15 Keiichi Morikuni

We review a recent approach for the simulation of many-body interacting systems based on an efficient generalization of the Lanczos method for Quantum Monte Carlo simulations. This technique allows to perform systematic corrections to a…

Strongly Correlated Electrons · Physics 2007-05-23 Sandro Sorella

A standard approach to approximate inference in state-space models isto apply a particle filter, e.g., the Condensation Algorithm.However, the performance of particle filters often varies significantlydue to their stochastic nature.We…

Artificial Intelligence · Computer Science 2013-01-14 Dirk Ormoneit , Christiane Lemieux , David J. Fleet

We study the universal properties of the Lanczos algorithm applied to finite-size many-body quantum systems. Focusing on autocorrelation functions of local operators and on their infinite-time behaviour at finite size, we conjecture that in…

Quantum Physics · Physics 2026-02-16 Luca Capizzi , Leonardo Mazza , Sara Murciano

Continuous time quantum walks provide an important framework for designing new algorithms and modelling quantum transport and state transfer problems. Often, the graph representing the structure of a problem contains certain symmetries that…

Quantum Physics · Physics 2015-11-03 Leonardo Novo , Shantanav Chakraborty , Masoud Mohseni , Hartmut Neven , Yasser Omar

Among randomized numerical linear algebra strategies, so-called sketching procedures are emerging as effective reduction means to accelerate the computation of Krylov subspace methods for, e.g., the solution of linear systems, eigenvalue…

Numerical Analysis · Mathematics 2024-08-02 Davide Palitta , Marcel Schweitzer , Valeria Simoncini

Models of quantum systems scale exponentially with the addition of single-particle states, which can present computationally intractable problems. Alternatively, quantum computers can store a many-body basis of $2^n$ dimensions on $n$…

Quantum Physics · Physics 2023-09-20 Amanda Bowman

The increasing imbalance between the computing capabilities of individual nodes and the internode bandwidth makes it highly desirable for any Lattice QCD algorithm to minimize the amount of internode communication. One of the relatively new…

High Energy Physics - Lattice · Physics 2019-01-09 Yong-Chull Jang , Chulwoo Jung

This survey explores modern approaches for computing low-rank approximations of high-dimensional matrices by means of the randomized SVD, randomized subspace iteration, and randomized block Krylov iteration. The paper compares the…

Numerical Analysis · Mathematics 2023-09-25 Joel A. Tropp , Robert J. Webber
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