Boosting quantum machine learning models with a multilevel combination technique: Pople diagrams revisited

P Zaspel, B Huang, H Harbrecht… - Journal of chemical …, 2018 - ACS Publications
Inspired by Pople diagrams popular in quantum chemistry, we introduce a hierarchical
scheme, based on the multilevel combination (C) technique, to combine various levels of …

A stable and mass-conserving sparse grid combination technique with biorthogonal hierarchical basis functions for kinetic simulations

T Pollinger, J Rentrop, D Pflüger, K Kormann - Journal of Computational …, 2023 - Elsevier
The exact numerical simulation of plasma turbulence is one of the assets and challenges in
fusion research. For grid-based solvers, sufficiently fine resolutions are often unattainable …

Analysis of tensor approximation schemes for continuous functions

M Griebel, H Harbrecht - Foundations of Computational Mathematics, 2023 - Springer
In this article, we analyze tensor approximation schemes for continuous functions. We
assume that the function to be approximated lies in an isotropic Sobolev space and discuss …

Fast discrete Fourier transform on generalized sparse grids

M Griebel, J Hamaekers - Sparse Grids and Applications-Munich 2012, 2014 - Springer
In this paper, we present an algorithm for trigonometric interpolation of multivariate functions
on generalized sparse grids and study its application for the approximation of functions in …

Approximation of bi-variate functions: singular value decomposition versus sparse grids

M Griebel, H Harbrecht - IMA journal of numerical analysis, 2014 - academic.oup.com
We compare the cost complexities of two approximation schemes for functions f∈ H p (Ω 1×
Ω 2) which live on the product domain Ω 1× Ω 2 of sufficiently smooth domains Ω 1⊂ ℝ n 1 …

Covariance regularity and -matrix approximation for rough random fields

J Dölz, H Harbrecht, C Schwab - Numerische Mathematik, 2017 - Springer
In an open, bounded domain D ⊂\mathbb R^ n D⊂ R n with smooth boundary ∂ D∂ D or
on a smooth, closed and compact, Riemannian n-manifold M ⊂\mathbb R^ n+ 1 M⊂ R n+ 1 …

First order 𝑘-th moment finite element analysis of nonlinear operator equations with stochastic data

A Chernov, C Schwab - Mathematics of Computation, 2013 - ams.org
We develop and analyze a class of efficient Galerkin approximation methods for uncertainty
quantification of nonlinear operator equations. The algorithms are based on sparse Galerkin …

On multilevel quadrature for elliptic stochastic partial differential equations

H Harbrecht, M Peters, M Siebenmorgen - Sparse grids and applications, 2012 - Springer
In this article, we show that the multilevel Monte Carlo method for elliptic stochastic partial
differential equations is a sparse grid approximation. By using this interpretation, the method …

Low-rank approximation of continuous functions in Sobolev spaces with dominating mixed smoothness

M Griebel, H Harbrecht, R Schneider - Mathematics of Computation, 2023 - ams.org
Let $\Omega _i\subset\mathbb {R}^{n_i} $, $ i= 1,\ldots, m $, be given domains. In this
article, we study the low-rank approximation with respect to $ L^ 2 (\Omega …

Generalized self-concordant analysis of Frank–Wolfe algorithms

P Dvurechensky, K Safin, S Shtern… - Mathematical Programming, 2023 - Springer
Projection-free optimization via different variants of the Frank–Wolfe method has become
one of the cornerstones of large scale optimization for machine learning and computational …