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Related papers: Canonical Forms for Unitary Congruence and *Congru…

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In this paper many classes of sets of matrices with entries in F (F=R, F=C, F=H) are introduced. Each class with the corresponding topology determines a real analytical, complex or symplectic manifold for F=R, F=C or F=H respectively. Any…

Differential Geometry · Mathematics 2007-05-23 Kostadin Trencevski , Samet Kera

The equivalence group is determined for systems of linear ordinary differential equations in both the standard form and the normal form. It is then shown that the normal form of linear systems reducible by an invertible point transformation…

Classical Analysis and ODEs · Mathematics 2015-02-26 JC Ndogmo

We exhibit an explicit, deterministic algorithm for finding a canonical form for a positive definite matrix under unimodular integral transformations. We use characteristic sets of short vectors and partition-backtracking graph software.…

Number Theory · Mathematics 2020-11-17 Mathieu Dutour Sikirić , Anna Haensch , John Voight , Wessel P. J. van Woerden

An observable canonical form is formulated for the set of rational systems on a variety each of which is a single-input-single-output, affine in the input, and a minimal realization of its response map. The equivalence relation for the…

Optimization and Control · Mathematics 2018-05-07 Jana Nemcova , Jan H. van Schuppen

Finitely generated Z-modules have canonical decompositions. When such modules are given in a finitely presented form there is a classical algorithm for computing a canonical decomposition. This is the algorithm for computing the Smith…

Group Theory · Mathematics 2009-09-25 George Havas , Derek F. Holt , Sarah Rees

We give an algorithm that uses only unitary transformations and for each square complex matrix constructs a *congruent matrix that is a direct sum of a nonsingular matrix and singular Jordan blocks.

Representation Theory · Mathematics 2007-10-04 Roger A. Horn , Vladimir V. Sergeichuk

It is known that if A and B are two n-by-n complex matrices and (A,A^T) is simultaneously equivalent to (B,B^T), then A is congruent to B. We extend this statement to multilinear forms.

Representation Theory · Mathematics 2007-10-04 Genrich R. Belitskii , Vladimir V. Sergeichuk

We show that the spectral theorem -- which we understand to be a statement that every self-adjoint matrix admits a certain type of canonical form under unitary similarity -- admits analogues over other $*$-algebras distinct from the complex…

Rings and Algebras · Mathematics 2023-01-25 Ran Gutin

Under categorial grammars that have powerful rules like composition, a simple n-word sentence can have exponentially many parses. Generating all parses is inefficient and obscures whatever true semantic ambiguities are in the input. This…

cmp-lg · Computer Science 2008-02-03 Jason Eisner

Starting from the observation that distinct notions of copying have arisen in different categorical fields (logic and computation, contrasted with quantum mechanics) this paper addresses the question of when, or whether, they may coincide.…

Category Theory · Mathematics 2013-05-21 Peter Hines

This paper is dedicated to the problem of verification of matrices for unitary similarity. For the case of nonderogatory matrices, we have been able to present the new solution for this problem based on geometric approach. The main…

Numerical Analysis · Mathematics 2013-03-11 Yuri R. Nesterenko

We study how small perturbations of a 2-by-2 complex matrix can change its canonical form for *congruence. We construct the Hasse diagram for the closure ordering on the set of *congruence classes of 2-by-2 matrices.

Representation Theory · Mathematics 2014-03-12 Vyacheslav Futorny , Lena Klimenko , Vladimir V. Sergeichuk

We compute a canonical circular-arc representation for a given circular-arc (CA) graph which implies solving the isomorphism and recognition problem for this class. To accomplish this we split the class of CA graphs into uniform and…

Data Structures and Algorithms · Computer Science 2018-02-02 Maurice Chandoo

A new syntactic characterization of problems complete via Turing reductions is presented. General canonical forms are developed in order to define such problems. One of these forms allows us to define complete problems on ordered…

Computational Complexity · Computer Science 2014-11-25 Vladimir Naidenko

Let $\C$ be a sequence of multisets of subspaces of a vector space $\F_q^k$. We describe a practical algorithm which computes a canonical form and the stabilizer of $\C$ under the group action of the general semilinear group. It allows us…

Information Theory · Computer Science 2013-05-07 Thomas Feulner

We look at explicit ways to bring one or two antiunitary symmetries into a standard form via unitary conjugation. We carefully reproduce Wigner's proof in two special cases, where the antiunitary operators square to $+I$, or to $-I$.…

Mathematical Physics · Physics 2025-08-22 Terry A. Loring

On conformally compact manifolds of arbitrary signature, we use conformal geometry to identify a natural (and very general) class of canonical boundary problems. It turns out that these encompass and extend aspects of already known…

Differential Geometry · Mathematics 2015-11-05 A. Rod Gover , Andrew Waldron

We argue that reducing nonlinear programming problems to a simple canonical form is an effective way to analyze them, specially when the problem is degenerate and the usual linear independence hypothesis does not hold. To illustrate this…

Optimization and Control · Mathematics 2018-04-02 Walter F. Mascarenhas

Complicated mathematical equations involving products of tensors with permutation symmetries, frequently encountered in fields such as general relativity and quantum chemistry (e.g., equations in high-order coupled cluster theories),…

Chemical Physics · Physics 2018-12-19 Zhendong Li , Sihong Shao , Wenjian Liu

Matrices over the dual numbers are considered. We propose an approach to classify these matrices up to similarity. Some preliminary results on the realization of this approach are obtained. In particular, we produce explicitly canonical…

Rings and Algebras · Mathematics 2009-10-06 I. M. Trishin