Optimization on the Extended Tensor-Train Manifold with Shared Factors

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Molozhavenko, Alexander, Rakhuba, Maxim
Format: Preprint
Published: 2025
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866912557938245632
author Molozhavenko, Alexander
Rakhuba, Maxim
author_facet Molozhavenko, Alexander
Rakhuba, Maxim
contents This paper studies tensors that admit decomposition in the Extended Tensor Train (ETT) format, with a key focus on the case where some decomposition factors are constrained to be equal. This factor sharing introduces additional challenges, as it breaks the multilinear structure of the decomposition. Nevertheless, we show that Riemannian optimization methods can naturally handle such constraints and prove that the underlying manifold is indeed smooth. We develop efficient algorithms for key Riemannian optimization components, including a retraction operation based on quasi-optimal approximation in the new format, as well as tangent space projection using automatic differentiation. Finally, we demonstrate the practical effectiveness of our approach through tensor approximation tasks and multidimensional eigenvalue problem.
format Preprint
id arxiv_https___arxiv_org_abs_2508_20928
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle Optimization on the Extended Tensor-Train Manifold with Shared Factors
Molozhavenko, Alexander
Rakhuba, Maxim
Numerical Analysis
53Z50, 65F15, 15A23, 15A69
This paper studies tensors that admit decomposition in the Extended Tensor Train (ETT) format, with a key focus on the case where some decomposition factors are constrained to be equal. This factor sharing introduces additional challenges, as it breaks the multilinear structure of the decomposition. Nevertheless, we show that Riemannian optimization methods can naturally handle such constraints and prove that the underlying manifold is indeed smooth. We develop efficient algorithms for key Riemannian optimization components, including a retraction operation based on quasi-optimal approximation in the new format, as well as tangent space projection using automatic differentiation. Finally, we demonstrate the practical effectiveness of our approach through tensor approximation tasks and multidimensional eigenvalue problem.
title Optimization on the Extended Tensor-Train Manifold with Shared Factors
topic Numerical Analysis
53Z50, 65F15, 15A23, 15A69
url https://arxiv.org/abs/2508.20928