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Related papers: Domains via approximation operators

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In this paper we study spectral properties of self-adjoint operators on a large class of geometries given via sofic groups. We prove that the associated integrated densities of states can be approximated via finite volume analogues. This is…

Spectral Theory · Mathematics 2012-12-21 Christoph Schumacher , Fabian Schwarzenberger

Our work is a fundamental study of the notion of approximation in V-categories and in (U,V)-categories, for a quantale V and the ultrafilter monad U. We introduce auxiliary, approximating and Scott-continuous distributors, the way-below…

Category Theory · Mathematics 2010-04-14 Dirk Hofmann , Pawel Waszkiewicz

In this paper, we consider the locally convex spaces of entire functions with growth given by proximate orders, and study the representation as a differential operator of a continuous homomorphism from such a space to another one. As a…

Functional Analysis · Mathematics 2020-03-26 Takashi Aoki , Ryuichi Ishimura , Yasunori Okada

This paper aims to characterize boundedness of composition operators on Besov spaces $B^s_{p,q}$ of higher order derivatives $s>1+1/p$ on the one-dimensional Euclidean space. In contrast to the lower order case $0<s<1$, there were a few…

Functional Analysis · Mathematics 2023-05-04 Masahiro Ikeda , Isao Ishikawa , Koichi Taniguchi

We observe that some natural mathematical definitions are lifting properties relative to simplest counterexamples, namely the definitions of surjectivity and injectivity of maps, as well as of being connected, separation axioms $T_0$ and…

History and Overview · Mathematics 2014-08-29 Misha Gavrilovich

Working constructively, we study continuous directed complete posets (dcpos) and the Scott topology. Our two primary novelties are a notion of intrinsic apartness and a notion of sharp elements. Being apart is a positive formulation of…

Logic · Mathematics 2023-09-13 Tom de Jong

We propose an extension of the framework for discussing the computational complexity of problems involving uncountably many objects, such as real numbers, sets and functions, that can be represented only through approximation. The key idea…

Computational Complexity · Computer Science 2013-05-03 Akitoshi Kawamura , Stephen Cook

We obtain approximation results for general positive linear operators satisfying mild conditions, when acting on discontinuous functions and absolutely continuous functions having discontinuous derivatives. The upper bounds, given in terms…

Probability · Mathematics 2024-10-29 José A. Adell , P. Garrancho , F. J. Martínez-Sánchez

Well-structured transition systems provide the right foundation to compute a finite basis of the set of predecessors of the upward closure of a state. The dual problem, to compute a finite representation of the set of successors of the…

Logic in Computer Science · Computer Science 2009-02-11 Alain Finkel , Jean Goubault-Larrecq

Working constructively, we study continuous directed complete posets (dcpos) and the Scott topology. Our two primary novelties are a notion of intrinsic apartness and a notion of sharp elements. Being apart is a positive formulation of…

Logic in Computer Science · Computer Science 2021-12-30 Tom de Jong

A popular way to approximate the Koopman operator's action on a finite-dimensional subspace of functions is via orthogonal projections. The quality of the projected model directly depends on the selected subspace, specifically on how close…

Optimization and Control · Mathematics 2025-01-15 Masih Haseli , Jorge Cortés

We use a model operator approach and the spectral theorem for self-adjoint operators in a Hilbert space to derive the basic results of abstract left-definite theory in a straightforward manner. The theory is amply illustrated with a variety…

Spectral Theory · Mathematics 2024-08-06 Christoph Fischbacher , Fritz Gesztesy , Paul Hagelstein , Lance Littlejohn

We introduce a notion of a noncommutative function defined on a domain of $d$-tuples of bounded operators on an infinite dimensional Hilbert space. Inverse and implicit function theorems in this setting are established. When these…

Functional Analysis · Mathematics 2021-08-25 Mark E. Mancuso

In this paper we develop a general theoretical tool for the establishment of the boundedness of notoriously difficult operators (such as potentials) on certain specific types of rearrangement-invariant function spaces from analogous…

Functional Analysis · Mathematics 2026-02-16 Zdeněk Mihula , Luboš Pick , Daniel Spector

We investigate two approximation relations on a T0 topological space, the n-approximation, and the d-approximation, which are generalizations of the way-below relation on a dcpo. Different kinds of continuous spaces are defined by the two…

General Topology · Mathematics 2022-07-08 Yuxu Chen , Hui Kou , Zhenchao Lyu

We introduce an abstract neural flow framework for neural networks and neural operators. The framework contains two continuous-depth models, namely neural flows with composition and separation structures, and covers both finite-dimensional…

Machine Learning · Computer Science 2026-05-27 Shuang Chen , Juncai He , Xue-Cheng Tai

We approximate functions defined on smooth bounded domains by elements of the eigenspaces of the Laplacian or the Stokes operator in such a way that the approximations are bounded and converge in both Sobolev and Lebesgue spaces. We prove…

Functional Analysis · Mathematics 2021-08-05 Charles L. Fefferman , Karol W. Hajduk , James C. Robinson

For smooth bounded open sets in euclidean space, we construct corresponding contractive linear extension operators for the space of continuous functions which preserve regularity of functions in the domain of the Robin Laplacian. We also…

Analysis of PDEs · Mathematics 2009-07-03 Robin Nittka

In a nutshell, submodular functions encode an intuitive notion of diminishing returns. As a result, submodularity appears in many important machine learning tasks such as feature selection and data summarization. Although there has been a…

Data Structures and Algorithms · Computer Science 2018-03-19 Marko Mitrovic , Moran Feldman , Andreas Krause , Amin Karbasi

The approximation of complex-valued functions is of fundamental importance as it generalizes classical approximation theory to the complex domain, providing a rigorous framework for amplitude and phase-dependent phenomena. In this paper, we…

Numerical Analysis · Mathematics 2025-11-05 Priyanka Majethiya , Shivam Bajpeyi