Finding tensor decompositions with sparse optimization

Abstract

In this paper, we suggest a new method for a given tensor to find CP decompositions using a less number of rank $1$ tensors. The main ingredient is the Least Absolute Shrinkage and Selection Operator (LASSO) by considering the decomposition problem as a sparse optimization problem. As applications, we design experiments to find some CP decompositions of the matrix multiplication and determinant tensors. In particular, we find a new formula for the $4\times 4$ determinant tensor as a sum of $12$ rank $1$ tensors.

19 pages, 2 figures. This paper supercedes arXiv:2303.07842