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Related papers: On General Closure Operators and Quasi Factorizati…

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We study the complexity of closure operators, with applications to machine learning and decision theory. In machine learning, closure operators emerge naturally in data classification and clustering. In decision theory, they can model…

Theoretical Economics · Economics 2022-05-25 Hamed Hamze Bajgiran , Federico Echenique

The purpose of this article is to propose and investigate a partial order structure weaker than the lattice structure and which have nice properties regarding closure operators. We extend accordingly closed pattern mining and formal concept…

Logic in Computer Science · Computer Science 2021-02-25 Henry Soldano

If a locally cartesian closed category carries a weak factorisation system, then the left maps are stable under pullback along right maps if and only if the right maps are closed under pushforward along right maps. We refer to this…

Category Theory · Mathematics 2024-04-25 Wijnand van Woerkom , Benno van den Berg

In this paper, we mainly consider quasi-cyclic (QC) codes over finite chain rings. We study module structures and trace representations of QC codes, which lead to some lower bounds on the minimum Hamming distance of QC codes. Moreover, we…

Information Theory · Computer Science 2013-09-09 Jian Gao , Linzhi Shen , Fang-Wei Fu

We prove that any weakly idempotent complete $d$-exact category is equivalent to a $d$-cluster tilting subcategory of a weakly idempotent complete exact category, and that any weakly idempotent complete algebraic $(d+2)$-angulated category…

Representation Theory · Mathematics 2026-05-26 Sondre Kvamme

A factorization theory is proposed for Wiener-Hopf plus Hankel operators with almost periodic Fourier symbols. We introduce a factorization concept for the almost periodic Fourier symbols such that the properties of the factors will allow…

Functional Analysis · Mathematics 2007-05-23 A. P. Nolasco , L. P. Castro

In this paper, we characterize the second bounded characteristic classes of foliated bundles in terms of the non-descendible quasi-morphisms on the universal covering of the structure group. As its application, we study the boundedness of…

Symplectic Geometry · Mathematics 2022-03-16 Morimichi Kawasaki , Shuhei Maruyama

In the context of finite tensor products of Hilbert spaces, we prove that similarity of a tensor product of operator semigroups to a contraction semigroup is equivalent to the corresponding similarity for each factor, after an appropriate…

Functional Analysis · Mathematics 2025-09-04 J. Oliva-Maza , Y. Tomilov

We study possibilities for algebraic closures, differences between definable and algebraic closures in first-order structures, and variations of these closures with respect to the bounds of cardinalities of definable sets and given sets of…

Logic · Mathematics 2023-07-25 Sergey V. Sudoplatov

A new class of operators, larger than $C$-symmetric operators and different than normal one, named $C$--normal operators is introduced. Basic properties are given. Characterizations of this operators in finite dimensional spaces using a…

Functional Analysis · Mathematics 2020-01-01 Marek Ptak , Katarzyna Simik , Anna Wicher

An $f$-structure on a manifold $M$ is an endomorphism field $\phi\in\Gamma(M,\End(TM))$ such that $\phi^3+\phi=0$. Any $f$-structure $\phi$ determines an almost CR structure $E_{1,0}\subset T_\C M$ given by the $+i$-eigenbundle of $\phi$.…

Differential Geometry · Mathematics 2012-01-17 Sean Fitzpatrick

Let $Y$ be a subspace of a topological vector space $X$, and $A\subset X$ an open convex set that intersects $Y$. We say that the property $(QE)$ [property $(CE)$] holds if every continuous quasiconvex [continuous convex] function on $A\cap…

Functional Analysis · Mathematics 2022-12-29 Carlo Alberto De Bernardi , Libor Veselý

The modern approach to $m$-form global symmetries in a $d$-dimensional quantum field theory (QFT) entails specifying dimension $d-m-1$ topological generalized symmetry operators which non-trivially link with $m$-dimensional defect…

High Energy Physics - Theory · Physics 2023-08-09 Jonathan J. Heckman , Max Hübner , Ethan Torres , Hao Y. Zhang

This work is concerned with the fundamental scaling laws of quasi-complementary sequence sets (QCSSs) by understanding how large the set size (denoted by $M$) can grow with the flock size ($K$) and the sequence length ($N$). We first…

Combinatorics · Mathematics 2026-04-16 Huaning Liu , Lirong Guo , Zilong Liu

This thesis proposes a framework based on a notion of combinatorial cell complex (cc) whose cells are defined simply as finite sets of vertices. The cells of a cc are subject to four axioms involving a rank function that assigns a rank (or…

Mathematical Physics · Physics 2022-05-03 Maxime Savoy

We give a classification of all quasitriangular structures and ribbon elements of $\mathcal{D}(G)$ explicitly in terms of group homomorphisms and central subgroups. This can equivalently be interpreted as an explicit description of all…

Quantum Algebra · Mathematics 2017-08-23 Marc Keilberg

This is a continuation of our earlier paper \cite{PT3}. We consider here operator-valued functions (or infinite matrix functions) on the unit circle $\T$ and study the problem of approximation by bounded analytic operator functions. We…

Functional Analysis · Mathematics 2007-05-23 V. V. Peller , S. R. Treil

We show that the class of inductively factored arrangements is closed under taking localizations. We illustrate the usefulness of this with an application.

Combinatorics · Mathematics 2016-02-24 Tilman Moeller , Gerhard Roehrle

Let $C$ be a simply laced generalized Cartan matrix. Given an element $b$ of the generalized braid semigroup related to $C$, we construct a collection of mutation-equivalent quivers with potentials. A quiver with potential in such a…

Representation Theory · Mathematics 2017-01-04 Efim Abrikosov

Quasi-abelian categories are abundant in functional analysis and representation theory. It is known that a quasi-abelian category $\mathcal{E}$ is a cotilting torsionfree class of an abelian category. In fact, this property characterizes…

Category Theory · Mathematics 2024-08-06 Ruben Henrard , Sondre Kvamme , Adam-Christiaan van Roosmalen , Sven-Ake Wegner