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Related papers: A recursive parameterisation of unitary matrices

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From the matrix point of view, we use the recursion to discuss four combinatorial numbers in terms of the integer lattice paths, this is different from Andr\'a's method (Andra). We give four tables and matrices, and their relations, and…

Combinatorics · Mathematics 2016-09-23 Jishe Feng

Recurrent neural networks (RNNs) are notoriously difficult to train. When the eigenvalues of the hidden to hidden weight matrix deviate from absolute value 1, optimization becomes difficult due to the well studied issue of vanishing and…

Machine Learning · Computer Science 2016-10-13 Martin Arjovsky , Amar Shah , Yoshua Bengio

One may identify the general properties of the neutrino mass matrix by generating many random mass matrices and testing them against the results of the neutrino experiments.

High Energy Physics - Phenomenology · Physics 2009-10-31 Kevin Cahill

Unitary transformations and density matrices are central objects in quantum physics and various tasks require to introduce them in a parameterized form. In the present article we present a parameterization of the unitary group…

Quantum Physics · Physics 2010-08-18 Christoph Spengler , Marcus Huber , Beatrix C. Hiesmayr

In terms of a rephasing invariant parametrization, the set of renormalization group equations (RGE) for Dirac neutrino parameters can be cast in a compact and simple form. These equations exhibit manifest symmetry under flavor permutations.…

High Energy Physics - Phenomenology · Physics 2016-07-26 S. H. Chiu , T. K. Kuo

Given a matrix A \in R^{m x n}, we present a randomized algorithm that sparsifies A by retaining some of its elements by sampling them according to a distribution that depends on both the square and the absolute value of the entries. We…

Information Theory · Computer Science 2014-04-02 Abhisek Kundu , Petros Drineas

This paper presents a regenerative variant of the classical Ulam-von Neumann Markov chain Monte Carlo algorithm for the approximation of the matrix inverse. The algorithm presented in this paper, termed regenerative Ulam-von Neumann…

Numerical Analysis · Mathematics 2025-08-21 Soumyadip Ghosh , Lior Horesh , Vassilis Kalantzis , Yingdong Lu , Tomasz Nowicki

We construct six unitary trace invariants for 2 by 2 quaternionic matrices which separate the unitary similarity classes of such matrices, and show that this set is minimal. We prove two quaternionic versions of a well known…

Commutative Algebra · Mathematics 2009-03-18 Dragomir Z. Djokovic , Benjamin H. Smith

Pseudo-unitary circuits are recurring in both S-matrix theory and analysis of No-Go theorems. We propose a matrix and diagrammatic representation for the operation that maps S-matrices to T-matrices and, consequently, a unitary group to a…

High Energy Physics - Theory · Physics 2025-12-04 Dennis Lima , Saif Al-Kuwari

This document contains a concise and unified reference for one of the existing mechanizations of the UD Kalman filter. The associated matrix algorithms are also included along with the corresponding references.

Systems and Control · Electrical Eng. & Systems 2022-06-30 J. Humberto Ramos , Kevin Brink , Prashant Ganesh , John E. Hurtado

The problem of finding a canonical form of complex matrices up to conjugacy with the set of canonical matrices being a union of affine planes in the matrix space is considered. A solution of the problem is given producing a new canonical…

Representation Theory · Mathematics 2011-11-01 Peteris Daugulis

Formula for the nth prime using elementary arithmetical functions based in a previous formula changing the characteristic function of prime numbers.

General Mathematics · Mathematics 2007-05-23 Sebastian Martin Ruiz

In this paper we analyse Cline's matrix equation, generalized Penrose's matrix system and a matrix system for k-commutative {1}-inverses. We determine reproductive and non-reproductive general solutions of analysed matrix equation and…

Rings and Algebras · Mathematics 2012-08-22 Branko Malesevic , Biljana Radicic

In this paper, we propose an iterative algorithm using polar decomposition to approximate a channel characterized by a single unitary matrix based on input-output quantum state pairs. In limited data, we state and prove that the optimal…

Numerical Analysis · Mathematics 2025-06-27 Matthew M. Lin , Hao-Wei Huang , Bing-Ze Lu

We construct quark mixing matrices within a group theoretic framework which is easily applicable to any number of generations. Familiar cases are retrieved and related, and it is hoped that our viewpoint may have advantages both…

High Energy Physics - Phenomenology · Physics 2019-08-17 K. J. Barnes , O. J. Senior , N. D. Virgo

The computation of matrix functions is a well-studied problem. Of special importance are the exponential and the logarithm of a matrix, where the latter also raises existence and uniqueness questions. This is particularly relevant in the…

Rings and Algebras · Mathematics 2024-06-17 Ellen Baake , Michael Baake

We give an overview of the existing algorithms to compute nonunique factorization invariants in finitely generated monoids.

Commutative Algebra · Mathematics 2015-04-29 P. A. García-Sánchez

Integrals for the product of unitary-matrix elements over the U(n) group will be discussed. A group-theoretical formula is available to convert them into a multiple sum, but unfortunately the sums are often tedious to compute. In this…

Mathematical Physics · Physics 2009-11-10 S. Aubert , C. S. Lam

In this paper, we study unirational differential curves and the corresponding differential rational parametrizations. We first investigate basic properties of proper differential rational parametrizations for unirational differential…

Algebraic Geometry · Mathematics 2020-01-27 Lei Fu , Wei Li

We provide a solution to the problem of simultaneous $diagonalization$ $via$ $congruence$ of a given set of $m$ complex symmetric $n\times n$ matrices $\{A_{1},\ldots,A_{m}\}$, by showing that it can be reduced to a possibly…

Optimization and Control · Mathematics 2021-02-10 Miguel D. Bustamante , Pauline Mellon , M. Victoria Velasco