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In this paper extensions of the classical Fourier, fractional Fourier and Radon transforms to superspace are studied. Previously, a Fourier transform in superspace was already studied, but with a different kernel. In this work, the…

Classical Analysis and ODEs · Mathematics 2008-05-14 Hendrik De Bie

The quaternion Fourier transform (qFT) is an important tool in multi-dimensional data analysis, in particular for the study of color images. An important problem when applying the qFT is the mismatch between the spatial and frequency…

Classical Analysis and ODEs · Mathematics 2015-06-24 Hendrik De Bie , Nele De Schepper , Todd A. Ell , Klaus Rubrecht , Stephen J. Sangwine

An involution is usually defined as a mapping that is its own inverse. In this paper, we study quaternion involutions that have the additional properties of distribution over addition and multiplication. We review formal axioms for such…

Rings and Algebras · Mathematics 2007-06-13 Todd A. Ell , Stephen J. Sangwine

Frames in a separable quaternionic Hilbert space were introduced and studied in [17] to have more applications. In this paper, we extend the study of frames in quaternionic Hilbert spaces and introduce different types of duals of a frame in…

Functional Analysis · Mathematics 2018-03-16 S. K. Sharma , Ghanshyam Singh , Soniya Sahu

Relying on rays, we search for submodules of a module V over a supertropical semiring on which a given anisotropic quadratic form is quasilinear. Rays are classes of a certain equivalence relation on V, that carry a notion of convexity,…

Rings and Algebras · Mathematics 2018-07-10 Zur Izhakian , Manfred Knebusch

Connect each vertex of a convex quadrilateral Q to the midpoint of the next (proceeding counterclockwise) side. The four connecting lines create an interior quadrilateral I. We study the ratio area(I)/area(Q). We also determine what happens…

General Mathematics · Mathematics 2007-09-17 J. M. Ash , M. A. Ash , P. F. Ash

Using a left multiplication defined on a right quaternionic Hilbert space, linear self-adjoint momentum operators on a right quaternionic Hilbert space are defined in complete analogy with their complex counterpart. With the aid of the…

Mathematical Physics · Physics 2017-09-13 B. Muraleetharan , K. Thirulogasanthar , I. Sabadini

Quadratic descent of hermitian and skew hermitian forms over division algebras with involution of the first kind in arbitrary characteristic is investigated and a criterion, in terms of systems of quadratic forms, is obtained. A refined…

Rings and Algebras · Mathematics 2020-02-26 Amir Hossein Nokhodkar

We propose a novel framework for fast integral operations by uncovering hidden geometries in the row and column structures of the underlying operators. This is accomplished through the \texttt{Questionnaire} algorithm, an iterative…

Numerical Analysis · Mathematics 2026-02-27 Pei-Chun Su , Ronald R. Coifman

Quantum theory may be formulated using Hilbert spaces over any of the three associative normed division algebras: the real numbers, the complex numbers and the quaternions. Indeed, these three choices appear naturally in a number of…

Quantum Physics · Physics 2015-05-27 John C. Baez

A banded matrix is a real square matrix where nonzero entries appear around the main diagonal. In this article, we consider linear complementarity properties of (variants) of banded matrices. Focusing on triangular matrices and the newly…

Optimization and Control · Mathematics 2026-03-12 Samapti Pratihar , M. Seetharama Gowda , K. C. Sivakumar

We recast spinful superconductivity as a \textit{quaternion field theory}, where a quaternion is a four-component hypercomplex number with units $(\boldsymbol{e}_x,\boldsymbol{e}_y,\boldsymbol{e}_z)$, that encodes the spin-singlet/triplet…

Superconductivity · Physics 2026-05-27 Christian Tantardini , Jacopo Masotti , Sabri F. Elatresh , Boris Yakobson

It is known that quaternions represent rotations in 3D Euclidean and Minkowski spaces. However, product by a quaternion gives rotation in two independent planes at once and to obtain single-plane rotations one has to apply by half-angle…

General Physics · Physics 2014-12-16 Merab Gogberashvili

Rotations on the 3-dimensional Euclidean vector-space can be represented by real quaternions, as was shown by Hamilton. Introducing complex quaternions allows us to extend the result to elliptic and hyperbolic rotations on the Minkowski…

Optics · Physics 2024-07-17 Pierre Pellat-Finet

Objects' rigid motions in 3D space are described by rotations and translations of a highly-correlated set of points, each with associated $x,y,z$ coordinates that real-valued networks consider as separate entities, losing information.…

Artificial Intelligence · Computer Science 2023-10-12 Guilherme Vieira , Eleonora Grassucci , Marcos Eduardo Valle , Danilo Comminiello

In this paper, we study a special one dimensional quaternion short-time Fourier transform (QSTFT). Its construction is based on the slice hyperholomorphic Segal-Bargmann transform. We discuss some basic properties and prove different…

Complex Variables · Mathematics 2020-09-02 Antonino De Martino , Kamal Diki

This report investigates the main definitions and fundamental properties of the fractional two-sided quaternionic Dunkl transform in two dimensions. We present key results concerning its structure and emphasize its connections to classical…

Functional Analysis · Mathematics 2025-10-14 Mohamed Essenhajy

We present a new simple proof of the fact that certain group manifolds as well as certain homogeneous spaces G/H of dimension 4n admit a quaternionic triple of integrable complex structures that are covariantly constant with respect to the…

Mathematical Physics · Physics 2020-07-15 A. V. Smilga

We solve the problem of Fourier transformation for the one-dimensional $q$-deformed Heisenberg algebra. Starting from a matrix representation of this algebra we observe that momentum and position are unbounded operators in the Hilbert…

High Energy Physics - Theory · Physics 2008-02-03 J. Schwenk

We study Fourier theory on quantum Euclidean space. A modified version of the general definition of the Fourier transform on a quantum space is used and its inverse is constructed. The Fourier transforms can be defined by their Bochner's…

Mathematical Physics · Physics 2011-08-08 Kevin Coulembier