Tensor rank bounds for point singularities in ℝ3


Loading...

Date

2022-04-14

Publication Type

Journal Article

ETH Bibliography

yes

Citations

Altmetric

Data

Abstract

We analyze rates of approximation by quantized, tensor-structured representations of functions with isolated point singularities in Double-struck capital R-3. We consider functions in countably normed Sobolev spaces with radial weights and analytic- or Gevrey-type control of weighted semi-norms. Several classes of boundary value and eigenvalue problems from science and engineering are discussed whose solutions belong to the countably normed spaces. It is shown that quantized, tensor-structured approximations of functions in these classes exhibit tensor ranks bounded polylogarithmically with respect to the accuracy epsilon is an element of (0,1) in the Sobolev space H-1. We prove exponential convergence rates of three specific types of quantized tensor decompositions: quantized tensor train (QTT), transposed QTT and Tucker QTT. In addition, the bounds for the patchwise decompositions are uniform with respect to the position of the point singularity. An auxiliary result of independent interest is the proof of exponential convergence of hp-finite element approximations for Gevrey-regular functions with point singularities in the unit cube Q = (0,1)(3). Numerical examples of function approximations and of Schrodinger-type eigenvalue problems illustrate the theoretical results.

Publication status

published

Editor

Book title

Volume

48 (3)

Pages / Article No.

18

Publisher

Springer

Event

Edition / version

Methods

Software

Geographic location

Date collected

Date created

Subject

Quantized tensor train; Tensor networks; Low-rank approximation; Exponential convergence; Schrödinger equation

Organisational unit

03435 - Schwab, Christoph / Schwab, Christoph check_circle

Notes

Funding

Related publications and datasets