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We define the notions of a compact perception pair, compactification of a perception pair, and compactification of a space of group equivariant non-expansive operators. We prove that every perception pair with totally bounded space of…

General Topology · Mathematics 2022-10-11 Faraz Ahmad

The main aim of this work is to present the interpretation of the Ising type models as a kind of field theory in the framework of noncommutative geometry. We present the method and construct sample models of field theory on discrete spaces…

High Energy Physics - Theory · Physics 2009-10-22 Andrzej Sitarz

Using the recently defined concept of Taylor measures, we propose a generalization of Taylor's theorem to measurable, non-analytic functions, that do not require differentiation. We study consequences of the generalization, including the…

Functional Analysis · Mathematics 2025-12-09 Athanasios Christou Micheas

This article provides a basic introduction to some concepts of non-commutative geometry. The importance of quantum groups and quantum spaces is stressed. Canonical non-commutativity is understood as an approximation to the quantum group…

High Energy Physics - Theory · Physics 2007-05-23 Michael Wohlgenannt

Divided into three parts, the first marks out enormous geometric issues with the notion of quasi-freenss of an algebra and seeks to replace this notion of formal smoothness with an approximation by means of a minimal unital commutative…

Rings and Algebras · Mathematics 2014-04-11 Anastasis Kratsios

We present a construction of algebras of generalized functions of Colombeau-type which, instead of asymptotic estimates with respect to a regularization parameter, employs only topological estimates on certain spaces of kernels for its…

Functional Analysis · Mathematics 2017-04-27 Eduard A. Nigsch

By utilizing the idea of Colombeau's generalized function, we introduce a notion of asymptotic map between arbitrary diffeological spaces. The category consisting of diffeological spaces and asymptotic maps is enriched over the category of…

Algebraic Topology · Mathematics 2024-04-12 Kazuhisa Shimakawa

Estimating the coefficient functionals on various classes of holomorphic functions traditionally forms an important field of geometric complex analysis and its mathematical and physical applications. These coefficients reflect fundamental…

Complex Variables · Mathematics 2025-07-29 Samuel L. Krushkal

In the paper, it is given isomorphic classification of $F$-spaces of $log$-integrable measurable functions constructed using different measure spaces. At the same time, it is proved that such spaces are non-isometric.

Functional Analysis · Mathematics 2020-09-25 R. Z. Abdullaev , B. A. Madaminov

We present geometric characterizations of the partial isometries, unitaries, and invertible operators in C*-algebras and von Neumann algebras.

Operator Algebras · Mathematics 2007-05-23 Charles Akemann , Nik Weaver

Let k be a perfect field and let K/k be a finite extension of fields. An arithmetic noncommutative projective line is a noncommutative space equal to the projectivization of the noncommutative symmetric algebra of a k-central two -sided…

Quantum Algebra · Mathematics 2014-05-30 Adam Nyman

This is a paper in a series that studies smooth relative Lie algebra homologies and cohomologies based on the theory of formal manifolds and formal Lie groups. In a previous paper, we introduce the notion of formal manifolds and develop the…

Functional Analysis · Mathematics 2024-07-15 Fulin Chen , Binyong Sun , Chuyun Wang

We consider composite functions in the elementary algebraic framework. Without any use of the Fourier transform, we find almost periodic orbits which suitably characterizes certain composite functions. In particular, we provide special…

Machine Learning · Computer Science 2025-06-17 Chikara Nakayama , Tsuyoshi Yoneda

We argue that there should exist a "noncommutative Fourier transform" which should identify functions of noncommutative variables (say, of matrices of indeterminate size) and ordinary functions or measures on the space of paths. Some…

Quantum Algebra · Mathematics 2007-05-23 M. Kapranov

We survey the operator algebras arising as commutants modulo normed ideals of finite sets of hermitian operators and connections to perturbations of operators and noncommutative geometry.

Operator Algebras · Mathematics 2019-10-28 Dan-Virgil Voiculescu

In this paper we establish a multivariable non-commutative generalization of L\"owner's classical theorem from 1934 characterizing operator monotone functions as real functions admitting analytic continuation mapping the upper complex…

Functional Analysis · Mathematics 2016-06-14 Miklós Pálfia

Let $X$ be a rearrangement-invariant space over a non-atomic $\sigma$-finite measure space $(\mathscr{R},\mu)$ and let $\alpha\in(0,\infty)$. We define the functional \begin{equation*} \|f\|_{X^{\langle \alpha \rangle}} =…

Functional Analysis · Mathematics 2021-09-13 Hana Turčinová

The characteristic function has been an important tool for studying completely non unitary contractions on Hilbert spaces. In this note, we consider completely non-coisometric contractive tuples of commuting operators on a Hilbert space…

Operator Algebras · Mathematics 2007-05-23 T. Bhattacharyya , J. Eschmeier , J. Sarkar

The algebra of functions on kappa-Minkowski noncommutative spacetime is studied as algebra of operators on Hilbert spaces. The representations of this algebra are constructed and classified. This new approach leads to a natural construction…

High Energy Physics - Theory · Physics 2008-11-26 Alessandra Agostini

We present some general theorems about operator algebras that are algebras of functions on sets, including theories of local algebras, residually finite dimensional operator algebras and algebras that can be represented as the scalar…

Operator Algebras · Mathematics 2009-07-30 Meghna Mittal , Vern Paulsen