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Related papers: Wirtinger's Calculus in general Hilbert Spaces

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We study embeddings between reproducing kernel Hilbert spaces $H(K)$ of functions of $d \in \mathbb{N} \cup \{\infty\}$ variables. The kernels $K$ are superpositions of weighted finite tensor products of a fixed univariate kernel. The basic…

Numerical Analysis · Mathematics 2026-05-01 Michael Gnewuch , Peter Kritzer , Klaus Ritter

This paper studies the construction of a refinement kernel for a given operator-valued reproducing kernel such that the vector-valued reproducing kernel Hilbert space of the refinement kernel contains that of the given one as a subspace.…

Machine Learning · Computer Science 2011-02-08 Yuesheng Xu , Haizhang Zhang , Qinghui Zhang

The Fourier transform and its inverse are well-known to have complex conjugate integral kernels. S.~Saitoh demonstrated that this relationship extends to the theory of integral transforms of Hilbert spaces of functions under certain…

Functional Analysis · Mathematics 2024-12-30 Akira Yamada

This paper introduces the bicomplex Prabhakar derivative, extending fractional calculus to four-dimensional bicomplex spaces. Using the generalized kernel involving bicomplex Prabhakar function, we construct the bicomplex Prabhakar…

Complex Variables · Mathematics 2026-03-10 Urvashi Purohit Sharma , Ritu Agarwal

In this paper, we illustrate the effectiveness of reproducing kernel Hilbert space techniques in the study of composition operators. For weighted Hardy spaces on the unit disk, we characterize the composition operators whose adjoint is…

Functional Analysis · Mathematics 2026-01-28 Preeti Kumari , P. Muthukumar , Antti Rasila

The necessary and sufficient conditions for existence of a generalized representer theorem are presented for learning Hilbert space-valued functions. Representer theorems involving explicit basis functions and Reproducing Kernels are a…

Machine Learning · Computer Science 2018-09-21 Sanket Diwale , Colin Jones

The purpose of this work is to explore the existence and properties of reproducing kernel Hilbert subspaces of $L^2(\C, \, d^2z/\pi)$ based on subsets of complex Hermite polynomials. The resulting coherent states (CS) form a family…

Mathematical Physics · Physics 2015-06-12 S. Twareque Ali , Fabio Bagarello , Jean Pierre Gazeau

This paper is a sequel to [6]. In that paper we transferred the discussions in [1] and [13] concerning almost invariant half-spaces for operators on complex Banach spaces to the context of operators on Hilbert space, and we gave easier…

Functional Analysis · Mathematics 2017-10-30 Il Bong Jung , Eungil Ko , Carl Pearcy

We describe a method to perform functional operations on probability distributions of random variables. The method uses reproducing kernel Hilbert space representations of probability distributions, and it is applicable to all operations…

Machine Learning · Statistics 2016-09-14 Bernhard Schölkopf , Krikamol Muandet , Kenji Fukumizu , Jonas Peters

A Hilbert space embedding of a distribution---in short, a kernel mean embedding---has recently emerged as a powerful tool for machine learning and inference. The basic idea behind this framework is to map distributions into a reproducing…

Machine Learning · Statistics 2020-12-15 Krikamol Muandet , Kenji Fukumizu , Bharath Sriperumbudur , Bernhard Schölkopf

We explicitly construct a heat kernel as a Neumann series for certain function spaces, such as $L^{1}$, $L^{2}$, and Hilbert spaces, associated to a locally compact Hausdorff space $\mathfrak{X}$ with Borel $\sigma$-algebra $\mathcal{B}$,…

Classical Analysis and ODEs · Mathematics 2026-01-01 Palle Jorgensen , Jay Jorgenson , Lejla Smajlovic

We consider frames F in a given Hilbert space, and we show that every F may be obtained in a constructive way from a reproducing kernel and an orthonormal basis in an ambient Hilbert space. The construction is operator-theoretic, building…

Classical Analysis and ODEs · Mathematics 2007-05-23 Palle E. T. Jorgensen

The purpose of this paper is to announce some new results on the structure of the higher order Euler-Lagrange mapping of the multiple-integral variational calculus on fibered manifolds,namely a description of its kernel and its image,and an…

Mathematical Physics · Physics 2007-05-23 Demeter Krupka

Prior information can be incorporated in matrix completion to improve estimation accuracy and extrapolate the missing entries. Reproducing kernel Hilbert spaces provide tools to leverage the said prior information, and derive more reliable…

Machine Learning · Statistics 2020-04-22 Pere Giménez-Febrer , Alba Pagès-Zamora , Georgios B. Giannakis

In this paper we combine the theory of reproducing kernel Hilbert spaces with the field of collocation methods to solve boundary value problems with special emphasis on reproducing property of kernels. From the reproducing property of…

Numerical Analysis · Mathematics 2019-03-26 Babak Azarnavid , Mahdi Emamjome , Mohammad Nabati , Saeid Abbasbandy

For a sequence $\mathbf w = \{w_j\}_{j = 2}^\infty$ of positive real numbers, consider the positive semi-definite kernel $\kappa_{\mathbf w}(s, u) = \sum_{j = 2}^\infty w_j j^{-s - \overline{u}}$ defined on some right-half plane $\mathbb…

Functional Analysis · Mathematics 2023-02-07 Chaman Kumar Sahu

A set of reproducing kernel Hilbert spaces are obtained on Hilbert spaces over quaternion slices with the aid of coherent states. It is proved that the so obtained set forms a measurable field of Hilbert spaces and their direct integral…

Mathematical Physics · Physics 2016-09-30 K. Thirulogasanthar , B. Muraleetharan

Given the reproducing kernel $k$ of the Hilbert space $\mathcal{H}_k$ we study spaces $\mathcal{H}_k(b)$ whose reproducing kernel has the form $k(1-bb^*)$, where $b$ is a row-contraction on $\mathcal{H}_k$. In terms of reproducing kernels…

Functional Analysis · Mathematics 2024-12-17 Alexandru Aleman , Frej Dahlin

The polynomial kernels are widely used in machine learning and they are one of the default choices to develop kernel-based classification and regression models. However, they are rarely used and considered in numerical analysis due to their…

We do a preliminary study of the reproducing kernel Hilbert space having as kernel $k^d$, where $d$ is a positive integer and $k$ is the reproducing kernel of the analytic Dirichlet space.

Complex Variables · Mathematics 2016-05-19 Nicola Arcozzi , Karl-Mikael Perfekt , Pavel Mozolyako , Stefan Richter , Giulia Sarfatti