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Related papers: A new series expansion for slice regular functions

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We study a novel spline-like basis, which we name the "falling factorial basis", bearing many similarities to the classic truncated power basis. The advantage of the falling factorial basis is that it enables rapid, linear-time computations…

Machine Learning · Statistics 2014-10-29 Yu-Xiang Wang , Alex Smola , Ryan J. Tibshirani

In this paper we introduce and study some basic properties of the Fock space (also known as Segal-Bargmann space) in the slice hyperholomorphic setting. We discuss both the case of slice regular functions over quaternions and also the case…

Complex Variables · Mathematics 2014-06-24 Daniel Alpay , Fabrizio Colombo , Irene Sabadini , Guy Salomon

We study the $L^p$ norm of the orthogonal projection from the space of quaternion valued $L^2$ functions to the closed subspace of slice $L^2$ functions.

Complex Variables · Mathematics 2015-06-23 Nicola Arcozzi , Giulia Sarfatti

The two function theories of monogenic and of slice monogenic functions have been extensively studied in the literature and were developed independently; the relations between them, e.g. via Fueter mapping and Radon transform, have been…

Complex Variables · Mathematics 2024-12-19 Zhenghua Xu , Irene Sabadini

In this paper, a Fourier series in fractional dimensional space is introduced for an arbitrarily periodic function $f(t;\alpha)$. We call it fractional Fourier series of the order $\alpha$. Extending the basis functions of the linear space…

General Mathematics · Mathematics 2022-12-02 Ali Dorostkar , Ahmad Sabihi

The main purpose of this paper is to prove some density results of polynomials in Fock spaces of slice regular functions. The spaces can be of two different kinds since they are equipped with different inner products and contain different…

Complex Variables · Mathematics 2018-12-10 Kamal Diki , Sorin G. Gal , Irene Sabadini

The slice Dirac operator over octonions is a slice counterpart of the Dirac operator over quaternions. It involves a new theory of stem functions, which is the extension from the commutative $ O(1) $ case to the non-commutative $ O(3) $…

Complex Variables · Mathematics 2019-12-11 Ming Jin , Guangbin Ren , Irene Sabadini

Many generalizations of continued fractions, where the reciprocal function has been replaced by a more general function, have been studied, and it is often asked whether such generalized expansions can have nice properties. For instance, we…

Number Theory · Mathematics 2007-05-23 Greg Martin

In our recent publication we obtained a series expansion of the arctangent function involving complex numbers. In this work we show that this formula can also be expressed as a real rational function.

General Mathematics · Mathematics 2017-01-19 S. M. Abrarov , B. M. Quine

The partial fraction expansion of coth($\pi$z), due to Euler, is generalized to power series having for coefficients the Riemann zeta function evaluated at certain arithmetic sequences. A further generalization using arbitrary Dirichlet…

Complex Variables · Mathematics 2015-11-17 Claude Henri Picard

A quaternionic matrix-valued regular function is a map $F: \Omega \rightarrow M_n(\mathbb{H})$ whose entries are (left) regular functions of a quaternion variable, where $\Omega$ is a domain in $\mathbb{H}$. Our aim is to bring out some…

Functional Analysis · Mathematics 2026-02-18 Sachindranath Jayaraman , Dhashna T. Pillai

This paper addresses the Corona problem for slice hyperholomorphic functions for a single quaternionic variable. While the Corona problem is well-understood in the context of one complex variable, it remains highly challenging in the case…

Complex Variables · Mathematics 2025-08-28 Fabrizio Colombo , Elodie Pozzi , Irene Sabadini , Brett D. Wick

Computations in high-dimensional spaces can often be realized only approximately, using a certain number of projections onto lower dimensional subspaces or sampling from distributions. In this paper, we are interested in pairs of…

Numerical Analysis · Mathematics 2025-02-26 Nicolaj Rux , Michael Quellmalz , Gabriele Steidl

In this article we investigate harmonicity, Laplacians, mean value theorems and related topics in the context of quaternionic analysis. We observe that a Mean Value Formula for slice regular functions holds true and it is a consequence of…

Complex Variables · Mathematics 2020-11-09 Cinzia Bisi , Joerg Winkelmann

The algebraic properties of formal power series, whose coefficients show factorial growth and admit a certain well-behaved asymptotic expansion, are discussed. It is shown that these series form a subring of $\mathbb{R}[[x]]$. This subring…

Combinatorics · Mathematics 2020-08-07 Michael Borinsky

We consider a quaternionic analogue of the univariate complex Hermite polynomials and study some of their analytic properties in some detail. We obtain their integral representation as well as the operational formulas of exponential and…

Complex Variables · Mathematics 2018-03-28 Amal El Hamyani , Allal Ghanmi

A formula for calculating Extensions of (mainly integral) Polynomial Functors is established, based upon projective resolutions. Sample computations are performed, which, in particular, exhibit a surprising non-trivial extension of Divided…

Representation Theory · Mathematics 2013-05-15 Qimh Richey Xantcha

The theory of the operator $$G(x) = |\underline{x}|^2 \frac{\partial }{\partial x_0} + \underline{x} \sum_{j=1}^n x_j \frac{\partial }{\partial x_j} $$ is deeply associated with the slice monogenic function theory and has grown in recent…

Complex Variables · Mathematics 2026-04-17 J. O. González-Cervantes , D. González-Campos , J. Bory-Reyes

We introduce a non-commutative resultant, for slice regular polynomials in two quaternionic variables, defined in terms of a suitable Dieudonn\'e determinant.We use this tool to investigate the existence of common zeros of slice regular…

Complex Variables · Mathematics 2024-03-27 Anna Gori , Giulia Sarfatti , Fabio Vlacci

Fractional $q$-extensions of some classical $q$-orthogonal polynomials are introduced and some of the main properties of the new defined functions are given. Next, a fractional $q$-difference equation of Gauss type is introduced and solved…

Classical Analysis and ODEs · Mathematics 2016-12-28 P. Njionou Sadjang , S. Mboutngam