Rank-Adaptive Tensor Methods for High-Dimensional Nonlinear PDEs

Abstract

We present a new rank-adaptive tensor method to compute the numerical solution of high-dimensional nonlinear PDEs. The method combines functional tensor train (FTT) series expansions, operator splitting time integration, and a new rank-adaptive algorithm based on a thresholding criterion that limits the component of the PDE velocity vector normal to the FTT tensor manifold. This yields a scheme that can add or remove tensor modes adaptively from the PDE solution as time integration proceeds. The new method is designed to improve computational efficiency, accuracy and robustness in numerical integration of high-dimensional problems. In particular, it overcomes well-known computational challenges associated with dynamic tensor integration, including low-rank modeling errors and the need to invert covariance matrices of tensor cores at each time step. Numerical applications are presented and discussed for linear and nonlinear advection problems in two dimensions, and for a four-dimensional Fokker–Planck equation.

Document Details

Document Type
Pub Defense Publication
Publication Date
Jun 24, 2021
Source ID
10.1007/s10915-021-01539-3

Entities

People

  • Abram Rodgers
  • Alec Dektor
  • Daniele Venturi

Organizations

  • Air Force Office of Scientific Research
  • Army Research Office

Tags

Readers

  • Calculus or Mathematical Analysis
  • Neural Network Machine Learning.