## 2012.30: Triangularizing Quadratic Matrix Polynomials

2012.30:
Françoise Tisseur and Ion Zaballa
(2013)
*Triangularizing Quadratic Matrix Polynomials.*
SIAM J. MATRIX ANAL. APPL., 34 (2).
pp. 312-337.
ISSN 1749-9097

*This is the latest version of this eprint.*

Full text available as:

PDF - Requires a PDF viewer such as GSview, Xpdf or Adobe Acrobat Reader 287 Kb |

DOI: 10.1137/120867640

## Abstract

We show that any regular quadratic matrix polynomial can be reduced to an upper triangular quadratic matrix polynomial over the complex numbers preserving the finite and infinite elementary divisors. We characterize the real quadratic matrix polynomials that are triangularizable over the real numbers and show that those that are not triangularizable are quasi-triangularizable with diagonal blocks of sizes $1\times 1$ and $2 \times 2$. We also derive complex and real Schur-like theorems for linearizations of quadratic matrix polynomials with nonsingular leading coefficients. In particular, we show that for any monic linearization $\l I+A$ of an $n\times n$ quadratic matrix polynomial there exists a nonsingular matrix defined in terms of $n$ orthonormal vectors that transforms $A$ to a companion linearization of a (quasi)-triangular quadratic matrix polynomial. This provides the foundation for designing numerical algorithms for the reduction of quadratic matrix polynomials to upper (quasi)-triangular form.

Item Type: | Article |
---|---|

Subjects: | MSC 2000 > 15 Linear and multilinear algebra; matrix theory MSC 2000 > 65 Numerical analysis |

MIMS number: | 2012.30 |

Deposited By: | Dr Françoise Tisseur |

Deposited On: | 08 November 2013 |

### Available Versions of this Item

- Triangularizing Quadratic Matrix Polynomials (deposited 08 November 2013)
**[Currently Displayed]**

Download Statistics: last 4 weeks

Repository Staff Only: edit this item