Results 51 to 60 of about 2,773,140 (200)

A Coarse Geometric Approach to Graph Layout Problems

open access: yesJournal of Graph Theory, Volume 113, Issue 2, Page 169-194, October 2026.
ABSTRACT We define a range of new coarse geometric invariants based on various graph–theoretic measures of complexity for finite graphs, including treewidth, pathwidth, cutwidth and bandwidth. We prove that, for bounded degree graphs, these invariants can be used to define functions which satisfy a strong monotonicity property, namely, they are ...
Wanying Huang   +3 more
wiley   +1 more source

On the chain of commuting operators on Banach spaces

open access: yesBulletin of the London Mathematical Society, Volume 58, Issue 9, September 2026.
Abstract An operator T$T$ on a Banach space is said to be of chain N$N$ if there exist non‐scalar operators S1,⋯,SN−1$S_1,\dots,S_{N-1}$ and a non‐zero compact operator K$K$ such that T↔S1↔S2↔⋯↔SN−1↔K,$$\begin{equation*} T \leftrightarrow S_1 \leftrightarrow S_2 \leftrightarrow \dots \leftrightarrow S_{N-1} \leftrightarrow K, \end{equation*}$$where A↔B$
Tomasz Szczepanski
wiley   +1 more source

Geometry of essential matrix ranges and the Smith–Ward problem for operator systems

open access: yesBulletin of the London Mathematical Society, Volume 58, Issue 9, September 2026.
Abstract A d$d$‐tuple of bounded linear selfadjoint operators acting on an infinite‐dimensional separable Hilbert space is said to have the Smith–Ward property if the identity map of the image of the operator system in the Calkin algebra has a completely positive lift.
Douglas Farenick   +2 more
wiley   +1 more source

Nilpotent Elements in Lie Algebras

open access: yesJournal of Algebra, 1990
A classical result of \textit{Fine} and \textit{Herstein} is that the number of n by n nilpotent matrices with entries in GF(q) is a power of q, that power being \(n^ 2-n\). Kaplansky formulates an analogous problem in Lie algebras as follows: For a simple Lie algebra L of n by n matrices with entries from a field of q elements, is the number of ...
openaire   +1 more source

On Weak-BCC-Algebras

open access: yesThe Scientific World Journal, 2013
We describe weak-BCC-algebras (also called BZ-algebras) in which the condition is satisfied only in the case when elements belong to the same branch. We also characterize ideals, nilradicals, and nilpotent elements of such algebras.
Janus Thomys, Xiaohong Zhang
doaj   +1 more source

On the generalization of pseudo p-closure in pseudo BCI-algebras [PDF]

open access: yesJournal of Hyperstructures
In this paper, the notion of generalization of pseudo p-closure, denoted by gcl, is introduced and its related properties are investigated. The gcl of subalgebras and pseudo-ideals is discussed.
Padena Pirzadeh Ahvazi   +2 more
doaj   +1 more source

Modular analogs of character formulas and minimal lifts of modular forms

open access: yesBulletin of the London Mathematical Society, Volume 58, Issue 9, September 2026.
Abstract If f$f$ is a mod‐3 eigenform of weight 2 and level Γ0(ℓ2)$\Gamma _0(\ell ^2)$ for a prime ℓ$\ell$ such that ℓ≡−1(mod3)$\ell \equiv -1 \pmod {3}$, and ℓ$\ell$ is a vexing prime for f$f$, we show that there is no obstruction to finding a minimal lift of f$f$, but that there is an obstruction to finding a nonminimal lift.
Patrick B. Allen, Preston Wake
wiley   +1 more source

A typical graph structure of a ring [PDF]

open access: yesTransactions on Combinatorics, 2015
The zero-divisor graph of a commutative ring R with respect to nilpotent elements is a simple undirected graph $Gamma_N^*(R)$ with vertex set Z_N(R)*, and two vertices x and y are adjacent if and only if xy is nilpotent and xy is nonzero, where Z_N(R)={x
R. Kala , S. Kavitha
doaj  

The probability of generating finite and profinite groups

open access: yesJournal of the London Mathematical Society, Volume 114, Issue 3, September 2026.
Abstract Famously, every finite simple group G$G$ can be generated by a pair of elements. Moreover, Liebeck and Shalev (1995) proved that the probability that a pair of elements generate G$G$ tends to 1 as |G|→∞$|G| \rightarrow \infty$. In this paper, we generalize this theorem of Liebeck and Shalev. Work of Lucchini and Menegazzo (1997) implies that a
Scott Harper, Martyn Quick
wiley   +1 more source

Regular Nilpotent Elements and Quantum Groups [PDF]

open access: yesCommunications in Mathematical Physics, 1999
23 pages, LaTeX ...
openaire   +2 more sources

Home - About - Disclaimer - Privacy