Results 71 to 80 of about 1,529 (200)
Journal of Algebra, 2007 Let \({\mathcal E}\colon N\rightarrowtail G\twoheadrightarrow Q\) be a group extension with coupling \(\chi\colon Q\to\text{Out\,}N\). If \(\Aut\,{\mathcal E}=\{\gamma\in\Aut\,G\mid N^\gamma=N\}\), \(\text{Comp}(\chi)\) the group of all compatible pairs for \(\chi\) and \(A\) the center of \(N\) regarded as a \(Q\)-module via \(\chi\) then it is known [
openaire +2 more sources
l‐threo‐d‐galacto‐Octitol: a curious non‐classical order–disorder polytype with an 88 Å axis
Acta Crystallographica Section B, Volume 82, Issue 3, Page 352-359, June 2026.The sugar alcohol l‐threo‐d‐galacto‐octitol crystallizes in a structure with P43212 pseudo‐symmetry and a highly elongated unit cell (c ≈ 88 Å). In distinct layers of the structure, symmetry is broken by an asymmetric hydrogen‐bonding network leading to polytypism, which is discussed in the framework of order–disorder theory.GalC8 [l‐threo‐d‐galacto ...
Nina Biedermann +5 more
wiley +1 more source
On inner automorphisms and certain central automorphisms of groups
Indian Journal of Pure and Applied Mathematics, 2014 Let \(G\) be a group and \(M,N\trianglelefteq G\). By definition an automorphism \(\alpha\) of \(G\) belongs to \(\Aut^M_N(G)\) if and only if \(g^{-1}g^\alpha\in M\) for all \(g\in G\) and \(\alpha\) fixes \(N\) elementwise. The paper under review is devoted to the study of groups \(G\) in which one of the following holds: \(\mathrm{Inn}(G)=\Aut^M_N(G)
Azhdari, Zahedeh +1 more
openaire +2 more sources
Bulletin of the London Mathematical Society, Volume 58, Issue 6, June 2026.Abstract Given r⩾3$r \geqslant 3$, we prove that there exists λ>0$\lambda >0$ depending only on r$r$ so that if G$G$ is a metric graph of rank r$r$ with metric entropy 1, then there exists a proper subgraph H$H$ of G$G$ with metric entropy at least λ$\lambda$. This answers a question of the second two authors together with Rieck. We interpret this as a
Tawfiq Hamed, Tarik Aougab, Matt Clay
wiley +1 more source
Rota-Baxter Operators of Weight Zero on CayleyDickson Algebra with Matrix Images
Известия Иркутского государственного университета: Серия "Математика"Rota-Baxter operators present a natural generalization of integration by parts formula for the integral operator. We consider Rota-Baxter operators of weight zero on split octonion algebra over a field of characteristic not 2.
A. S. Panasenko
doaj +1 more source
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
On the Structure of Weyl-Type, Witt-Type, and Non-Associative Algebras over Expolynomial Rings
MathematicsThis paper introduces a generalized class of Weyl-type, Witt-type, and non-associative algebras constructed over an exponential–polynomial (expolynomial) framework.
Supriya Sharma +2 more
doaj +1 more source
On structure of isomorphisms of universal graphic automata [PDF]
Известия Саратовского университета. Новая серия: Математика. Механика. ИнформатикаAutomata theory is one of the branches of mathematical cybernetics, that studies information transducers that arise in many applied problems. The major objective of automata theory is to develop methods by which one can describe and analyze the dynamic ...
Molchanov, Vladimir Aleksandrovich +1 more
doaj +1 more source
A characterization of metaplectic time–frequency representations
Bulletin of the London Mathematical Society, Volume 58, Issue 6, June 2026.Abstract We characterize all time–frequency representations that satisfy a general covariance property: any weak*‐continuous bilinear mapping that intertwines time–frequency shifts on the configuration space with time–frequency shifts on phase space is a multiple of a metaplectic time–frequency representation. This characterization offers an intrinsic,
Karlheinz Gröchenig, Irina Shafkulovska
wiley +1 more source
An identity involving automorphisms of prime rings inspired by Posner's theorem
Journal of Taibah University for Science, 2018 Let ${\mathcal R}$ be a prime ring with centre ${\mathcal Z}(\mathcal {R})$, $\mathcal {L}$ a non-zero Lie ideal of ${\mathcal R}$, and σ a non-trivial automorphism of ${\mathcal R}$ such that $[[\sigma (u),u], \sigma (u)] \in \mathcal {Z}(\mathcal {R})$
Mohammad Ashraf, Sajad Ahmad Pary
doaj +1 more source