Results 31 to 40 of about 3,178 (180)
On the automorphisms of the power semigroups of a numerical semigroup
Transactions of the London Mathematical Society, Volume 13, Issue 1, December 2026.Abstract If H$H$ is a numerical semigroup (i.e., a cofinite subset of the non‐negative integers closed under addition), then the collection of all non‐empty subsets of H$H$ forms a semigroup P(H)$\mathcal {P}(H)$ under the sumset operation induced by addition in H$H$.
Salvatore Tringali, Kerou Wen
wiley +1 more source
Endomorphisms of Banach algebras of infinitely differentiable functions [PDF]
, 1999 In this note we study the endomorphisms of certain Banach algebras of infinitely differentiable functions on compact plane sets, associated with weight sequences M. These algebras were originally studied by Dales, Davie and McClure.
Kamowitz, Herbert, Feinstein, Joel
core
On the tightness of left‐invariant contact structures
Bulletin of the London Mathematical Society, Volume 58, Issue 6, June 2026.Abstract We prove that all left‐invariant contact structures on three‐dimensional Lie groups are tight. The argument is based on Riemannian methods and establishes a unique factorization property for any Lie group admitting a left‐invariant contact structure, other than SU(2)$\mathrm{SU}(2)$. We then make use of such factorization property to construct
Eugenio Bellini
wiley +1 more source
Semirings whose additive endomorphisms are multiplicative [PDF]
, 1993 summary:A ring or an idempotent semiring is associative provided that additive endomorphisms are ...
Kepka, Tomáš
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The singularity category and duality for complete intersection groups
Bulletin of the London Mathematical Society, Volume 58, Issue 6, June 2026.Abstract If G$G$ is a finite group, the structure of the modular representation theory depends on the cochains C∗(BG;k)$C^*(BG; k)$, viewed as a commutative ring spectrum. We consider here its singularity category (in the sense of the author and Stevenson [Adv. Math.
J. P. C. Greenlees
wiley +1 more source
On the cohomology of finite‐dimensional nilpotent groups and lie rings
Bulletin of the London Mathematical Society, Volume 58, Issue 6, June 2026.Abstract We establish vanishing results for the first cohomology group of nilpotent groups and Lie rings when the submodule of invariants is trivial. Our results are obtained within a model‐theoretic setting, namely for structures that are definable in a finite‐dimensional theory, which encompasses algebraic groups over algebraically closed fields ...
Samuel Zamour
wiley +1 more source
On the ring of inertial endomorphisms of an abelian p-group [PDF]
, 2012 An endomorphisms $\varphi$ of a group $G$ is said inertial if $\forall H\le G$ \ \ $|\varphi(H):(H\cap \varphi(H))|
RINAURO, Silvana +3 more
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Idempotent Pre-Endomorphisms of Algebras
, 2023 In the study of pre-Lie algebras, the concept of pre-morphism arises naturally as a generalization of the standard notion of morphism. Pre-morphisms can be defined for arbitrary (not-necessarily associative) algebras over any commutative ring $k$ with ...
Ebrahim, Fatma Azmy, Facchini, Alberto
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The N‐prime graph and the Subgroup Isomorphism Problem
Journal of the London Mathematical Society, Volume 113, Issue 6, June 2026.Abstract We introduce a directed graph related to a group G$G$, which we call the N‐prime graph ΓN(G)$\Gamma _{\rm {N}}(G)$ of G$G$ and is a refinement of the classical Gruenberg–Kegel graph. The vertices of ΓN(G)$\Gamma _{\rm {N}}(G)$ are the primes p$p$ such that G$G$ has an element of order p$p$, and, for distinct vertices p$p$ and q$q$, the arc q→p$
Emanuele Pacifici +2 more
wiley +1 more source
Infinitesimal Stability of Anosov Endomorphisms
, 1996 It is well known that infinitesimal stability of diffeomorphisms is an open property. But infinitesimal stability of endomorphisms is not an open property.
Ikeda, Hiroshi
core +1 more source