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Related papers: Ultralocally Closed Clones

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An open (resp., closed) subset A of a topological space (X, T ) is called C-open (resp., C-closed) set if cl(A) \ A (resp., A \ int(A)) is a countable set. This paper aims to present the concept of C-open and C-closed sets. We first…

General Topology · Mathematics 2023-05-08 M. H. Alqahtani

We prove that every bounded local triple derivation on a unital C*-algebra is a triple derivation. A similar statement is established in the category of unital JB*-algebras.

Operator Algebras · Mathematics 2012-08-17 Maria Burgos , Francisco J. Fernández-Polo , Jorge J. Garcés , Antonio M. Peralta

In 1986, the second author classified the minimal clones on a finite universe into five types. We extend this classification to infinite universes and to multiclones. We show that every non-trivial clone contains a "small" clone of one of…

Logic · Mathematics 2007-05-23 Maurice Pouzet , Ivo G. Rosenberg

Let X be an infinite set of regular cardinality. We determine all clones on X which contain all almost unary functions. It turns out that independently of the size of X, these clones form a countably infinite descending chain. Moreover, all…

Rings and Algebras · Mathematics 2007-05-23 Michael Pinsker

Every clone of functions comes naturally equipped with a topology---the topology of pointwise convergence. A clone $\mathfrak{C}$ is said to have automatic homeomorphicity with respect to a class $\mathcal{C}$ of clones, if every…

Logic · Mathematics 2017-04-04 Christian Pech , Maja Pech

Several sets of quaternionic functions are described and studied with respect to hyperholomorphy, addition and (non commutative) multiplication, on open sets of $\mathbb H$. The aim is to get a local function theory.

Complex Variables · Mathematics 2014-03-11 Pierre Dolbeault

Clonoids are sets of finitary operations between two algebraic structures that are closed under composition with their term operations on both sides. We conjecture that, for finite modules $\mathbf A$ and $\mathbf B$ there are only finitely…

Rings and Algebras · Mathematics 2026-02-05 Stefano Fioravanti , Michael Kompatscher , Bernardo Rossi

Our motivating question was whether all traces on a U-ultrapower of a C*-algebra A, where U is a non-principal ultrafilter on N, are necessarily U-limits of traces on A. We show that this is false so long as A has infinitely many extremal…

Operator Algebras · Mathematics 2017-02-10 Tristan Bice , Ilijas Farah

We introduce the notion of clone algebra, intended to found a one-sorted, purely algebraic theory of clones. Clone algebras are defined by true identities and thus form a variety in the sense of universal algebra. The most natural clone…

Logic · Mathematics 2021-01-19 Antonio Bucciarelli , Antonino Salibra

Algebraic properties of $n$-place opening operations on a fixed set are described. Conditions under which a Menger algebra of rank $n$ can be represented by $n$-place opening operations are found.

Rings and Algebras · Mathematics 2015-01-27 Wieslaw A. Dudek , Valentin S. Trokhimenko

We study closedness of the range, adjointability and generalized invertibility of modular operators between Hilbert modules over locally C*-algebras of coefficients. Our investigations and the recent results of M. Frank [Characterizing…

Operator Algebras · Mathematics 2011-08-31 Kamran Sharifi

The subsumption problem with respect to terminologies in the description logic ALC is EXPTIME-complete. We investigate the computational complexity of fragments of this problem by means of allowed Boolean operators. Hereto we make use of…

Logic in Computer Science · Computer Science 2012-05-04 Arne Meier

It is shown that if $A$ is a uniform algebra generated by real-analytic functions on a suitable compact subset $K$ of a real-analytic variety such that the maximal ideal space of $A$ is $K$, and every continuous function on $K$ is locally a…

Complex Variables · Mathematics 2016-12-28 John T. Anderson , Alexander J. Izzo

For each clone C on a set A there is an associated equivalence relation analogous to Green's R-relation, which relates two operations on A if and only if each one is a substitution instance of the other using operations from C. We study the…

Rings and Algebras · Mathematics 2016-11-22 Erkko Lehtonen , Agnes Szendrei

We construct dense, unconditional subalgebras of the reduced group $C^*$-algebra of a word-hyperbolic group, which are closed under holomorphic functional calculus and possess many bounded traces. Applications to the cyclic cohomology of…

Operator Algebras · Mathematics 2009-04-24 Michael Puschnigg

Clonoids are sets of finitary functions from an algebra $\mathbb{A}$ to an algebra $\mathbb{B}$ that are closed under composition with term functions of $\mathbb{A}$ on the domain side and with term functions of $\mathbb{B}$ on the codomain…

Rings and Algebras · Mathematics 2024-04-17 Peter Mayr , Patrick Wynne

Clones of functions play a foundational role in both universal algebra and theoretical computer science. In this work, we introduce clone merge monoids (cm-monoids), a unifying one-sorted algebraic framework that integrates abstract clones,…

Category Theory · Mathematics 2025-01-28 Antonio Bucciarelli , Pierre-Louis Curien , Antonino Salibra

Let $M$ be a $C$-minimal structure and $T$ its canonical tree (which corresponds in an ultrametric space to the set of closed balls with radius different than $\infty$ ordered by inclusion). We present a description of definable locally…

Logic · Mathematics 2014-10-14 Pablo Cubides Kovacsics

We introduce a quite large class of functions (including the exponential function and the power functions with exponent greater than one), and show that for any element $f$ of this function class, a self-adjoint element $a$ of a…

Operator Algebras · Mathematics 2017-05-04 Dániel Virosztek

The article is devoted to the investigation of operators on a non locally compact group algebra. Their isomorphisms are also studied.

Functional Analysis · Mathematics 2018-12-18 S. V. Ludkovsky