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Related papers: The structure of weak coalgebra-Galois extensions

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The notion of weak tiling played a key role in the proof of Fuglede's spectral set conjecture for convex domains, due to the fact that every spectral set must weakly tile its complement. In this paper, we revisit the notion of weak tiling…

Classical Analysis and ODEs · Mathematics 2025-09-17 Mihail N. Kolountzakis , Nir Lev , Máté Matolcsi

We prove the polynomiality of the bigraded ring $J_{*,*}^{w, W}(F_4)$ of weak Jacobi forms for the root system $F_4$ which are invariant with respect to the corresponding Weyl group. This work is a continuation of the joint article with…

Algebraic Geometry · Mathematics 2020-07-15 Dmitrii Adler

In this paper, we prove the integrality conjecture for quotient stacks arising from weakly symmetric representations of reductive groups. Our main result is a decomposition of the cohomology of the stack into finite-dimensional components…

Representation Theory · Mathematics 2026-01-21 Lucien Hennecart

Many combinatorial proofs rely on induction. When these proofs are formulated in traditional language, they can be bulky and unmanageable. Coalgebras provide a language which can reduce reduce many inductive proofs in graded poset theory to…

Combinatorics · Mathematics 2022-10-07 MLE Slone

We prove the weak positivity of the kernels of Kodaira-Spencer- type maps for pure Hodge module extensions of generically defined variations of Hodge structure.

Algebraic Geometry · Mathematics 2016-03-03 Mihnea Popa , Lei Wu

We introduce the notions of a mutually algebraic structures and theories and prove many equivalents. A theory $T$ is mutually algebraic if and only if it is weakly minimal and trivial if and only if no model $M$ of $T$ has an expansion…

Logic · Mathematics 2012-07-25 Michael C. Laskowski

The paper studies the structure of restricted Leibniz algebras. More specifically speaking, we first give the equivalent definition of restricted Leibniz algebras, which is by far more tractable than that of a restricted Leibniz algebras in…

Rings and Algebras · Mathematics 2014-04-01 Baoling Guan , Liangyun Chen

In this short note, we show that the cohomology of an algebra entwined with a coalgebra as defined by T. Brzezi\'nski (J. Algebra 235 (2001), no. 1, 176--202; arXiv:math.RA/9909108) computes the Hochschild cohomology of the subalgebra of…

Quantum Algebra · Mathematics 2007-05-23 Mariano Suarez-Alvarez

We present the universal theory of weak crossed biproducts, and we prove that every weak projection of weak bialgebras induces an example of this crossed structure. As an example, we give the construction of a weak projection of a weak…

Quantum Algebra · Mathematics 2009-10-30 J. M. Fernández Vilaboa , R. González Rodríguez , A. B. Rodríguez Raposo

We use techniques of relative algebraic K-theory to develop a common refinement of the existing theories of metrized and hermitian Galois structures in arithmetic. As a first application of this very general approach, we then use it to…

Number Theory · Mathematics 2020-03-25 Werner Bley , David Burns , Carl Hahn

Strong bisimulation for labelled transition systems is one of the most fundamental equivalences in process algebra, and has been generalised to numerous classes of systems that exhibit richer transition behaviour. Nearly all of the ensuing…

Logic in Computer Science · Computer Science 2014-05-05 Sergey Goncharov , Dirk Pattinson

The main objective of this project is to determine all irreducible modules of a given modular Lie algebra. In contrast to ordinary Lie algebras, modular Lie algebras require an additional structure known as the p-mapping. The minimal…

Rings and Algebras · Mathematics 2025-11-05 Eun H. Park

We develop a general approach to the problem of classification of weak coideal C*-subalgebras of weak Hopf C*-algebras. As an example, we consider weak Hopf C*-algebras and their weak coideal C*-subalgebras associated with Tambara Yamagami…

Quantum Algebra · Mathematics 2020-07-01 Leonid Vainerman , Jean-Michel Vallin

Given a unital C*-subalgebra of B(H), we study the set of all possible images of its injective envelope that are contained in B(H) and their position relative to the double commutant of the algebra in order to obtain more information about…

Operator Algebras · Mathematics 2008-07-21 Vern I. Paulsen

The class of weak BCK-algebras is obtained by weakening one of standard BCK axioms. It is known that every weak BCK-algebra is completely determined by the structure of its initial segments. We review several natural classes of commutative…

Logic · Mathematics 2015-02-10 Janis Cirulis

In a recent article, the coordinate ring of the nodal cubic was given the structure of a quantum homogeneous space. Here the corresponding coalgebra Galois extension is expressed in terms of quantum groups at roots of unity, and is shown to…

Quantum Algebra · Mathematics 2018-12-19 Ulrich Kraehmer , Manuel Martins

We introduce the notion of weakly extendible cardinals and show that these cardinals are characterized in terms of weak compactness of second order logic. The consistency strength and largeness of weakly extendible cardinals are located…

Logic · Mathematics 2023-01-06 Sakaé Fuchino , Hiroshi Sakai

We present a conservative extension ICaTT of the dependent type theory CaTT for weak $\omega$-categories with a type witnessing coinductive invertibility of cells. This extension allows for a concise description of the "walking equivalence"…

Category Theory · Mathematics 2026-02-19 Thibaut Benjamin , Camil Champin , Ioannis Markakis

The paper introduces the notion of a locally coalgebra-Galois extension and, as its special case, a locally cleft extension. The necessary and sufficient conditions for a locally coalgebra-Galois extension to be a (global) coalgebra-Galois…

Quantum Algebra · Mathematics 2007-05-23 Bartosz Zielinski

For a twisted $C^*$-dynamical system $(\mathscr{A},\mathbb{R}^n,\alpha,e)$ over a unital $C^*$-algebra we establish a weakly parametric pseudodifferential calculus analogously to the celebrated weakly parametric calculus due to Grubb and…

Operator Algebras · Mathematics 2024-05-14 Gihyun Lee , Matthias Lesch