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Related papers: On centers of blocks with non-cyclic defect groups

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We analyze a zeroth-order particle algorithm for the global optimization of a non-convex function, focusing on a variant of Consensus-Based Optimization (CBO) with small but fixed noise intensity. Unlike most previous studies restricted to…

Optimization and Control · Mathematics 2025-11-24 Pascal Bianchi , Radu-Alexandru Dragomir , Victor Priser

The exterior degree of a finite group has been introduced in [P. Niroomand and R. Rezaei, On the exterior degree of finite groups, Comm. Algebra 39 (2011), 335--343] and the present paper is devoted to study the exterior degree of infinite…

Group Theory · Mathematics 2018-12-14 Rashid Rezaei , Francesco G. Russo

We prove three theorems giving extremal bounds on the incidence structures determined by subsets of the points and blocks of a balanced incomplete block design (BIBD). These results generalize and strengthen known bounds on the number of…

Combinatorics · Mathematics 2016-12-28 Ben Lund , Shubhangi Saraf

We generalize to the case of singular blocks the result in \cite{BeLa} that describes the center of the principal block of a small quantum group in terms of sheaf cohomology over the Springer resolution. Then using the method developed in…

Representation Theory · Mathematics 2021-03-04 Anna Lachowska , You Qi

In this paper, we characterize finite group $G$ with unique proper non-abelian element centralizer. This improves \cite[Theorem 1.1]{nab}. Among other results, we have proved that if $C(a)$ is the proper non-abelian element centralizer of…

Group Theory · Mathematics 2020-10-23 Sekhar Jyoti Baishya

In this paper we introduce the notion of the center $ZBin(X)$ in the semigroup $Bin(X)$ of all binary systems on a set $X$, and show that if $(X,\bullet)\in ZBin(X)$, then $x\not=y$ implies $\{x,y\}=\{x\bullet y,y\bullet x\}$.Moreover, we…

Rings and Algebras · Mathematics 2020-10-20 Hiba F. Fayoumi

In this note we give applications of recent results coming mostly from the third paper of this series. It is shown that the number of irreducible characters in a $p$-block of a finite group with abelian defect group $D$ is bounded by $|D|$…

Representation Theory · Mathematics 2015-03-31 Benjamin Sambale

We investigate deformations of a skew group algebra that arise from a finite group acting on a polynomial ring. When the characteristic of the underlying field divides the order of the group, a new type of deformation emerges that does not…

Rings and Algebras · Mathematics 2013-12-13 Anne V. Shepler , Sarah Witherspoon

Let $A$ be a right Ore domain, $Z(A)$ be the center of $A$ and $Q_r(A)$ be the right total ring of fractions of $A$. If $K$ is a field and $A$ is a $K$-algebra, in this short paper we prove that if $A$ is finitely generated and ${\rm…

Rings and Algebras · Mathematics 2019-12-17 Oswaldo Lezama , Helbert Venegas

This paper studies the last-column-block-augmented northwest-corner truncation (LC-block-augmented truncation, for short) of discrete-time block-monotone Markov chains under subgeometric drift conditions. The main result of this paper is to…

Probability · Mathematics 2016-11-23 Hiroyuki Masuyama

It is well-known that the central extensions of the loop group of a compact, simple and 1-connected Lie group are parametrised by their level $k \in Z$. This article concerns the question how much can be said for arbitrary $k \in R$ and we…

Mathematical Physics · Physics 2011-03-04 Christoph Wockel

In this paper we classify all blocks with defect group $C_{2^n}\times C_2\times C_2$ up to Morita equivalence. Together with a recent paper of Wu, Zhang and Zhou, this completes the classification of Morita equivalence classes of $2$-blocks…

Representation Theory · Mathematics 2017-10-16 Charles Eaton , Michael Livesey

We present a strong upper bound on the number k(B) of irreducible characters of a p-block B of a finite group G in terms of local invariants. More precisely, the bound depends on a chosen major B-subsection (u,b), its normalizer N_G(\langle…

Representation Theory · Mathematics 2018-07-24 Benjamin Sambale

By imposing conditions upon the index of a self-centralizing subgroup of a group, and upon the index of the center of the group, we are able to classify the Chermak-Delgado lattice of the group. This is our main result. We use this result…

Group Theory · Mathematics 2025-03-18 Ryan McCulloch , Marius Tărnăuceanu

Brou\'e, Malle and Rouquier conjectured in that the center of the pure braid group of an irreducible finite complex reflection group is cyclic. We prove this conjecture, for the remaining exceptional types, using the analogous result for…

Group Theory · Mathematics 2013-05-02 François Digne , Ivan Marin , Jean Michel

The purpose of this work is to extend the study of the commutative rings whose lattice of ideals can be a structure of BL-algebra as carry out by Heubo et al in 2018, to non commutative rings appointed in the work as pseudo BL-rings. We…

Rings and Algebras · Mathematics 2021-04-20 Surdive Atamewoue Tsafack , Arnaud Fobasso Tchinda , Yuming Feng , Selestin Ndjeya

We characterize when a finite group G possesses a Sylow 3-subgroup P with abelianization of order 9 in terms of the number of height zero characters lying in the principal 3-block of G, settling a conjecture put forward by Navarro, Sambale,…

Group Theory · Mathematics 2024-07-16 Eugenio Giannelli , Noelia Rizo , A. A. Schaeffer Fry , Carolina Vallejo

We study groups having the property that every non-cyclic subgroup contains its centralizer. The structure of nilpotent and supersolvable groups in this class is described. We also classify finite $p$-groups and finite simple groups with…

Group Theory · Mathematics 2014-01-28 Costantino Delizia , Urban Jezernik , Primož Moravec , Chiara Nicotera

The c-dimension of a group G is the maximal length of a chain of nested centralizers in G. We prove that a locally finite group of finite c-dimension k has less than 5k nonabelian composition factors.

Group Theory · Mathematics 2018-10-30 Alexandr Buturlakin , Andrey V. Vasil'ev

A family of groups is called (maximal) cyclic bounded ((M)CB) if, for every natural number $n$, there are only finitely many groups in the family with at most $n$ (maximal) cyclic subgroups. We prove that the family of groups of prime power…

Group Theory · Mathematics 2024-05-21 Xiaofang Gao , Martino Garonzi