Results 111 to 120 of about 3,478,615 (190)
Line Graphs of Multigraphs and the Forbidden Graph E 6
ABSTRACT The line graph Γ of a multigraph Δ is the graph whose vertices are the edges of Δ, where two such edges are adjacent if and only if they meet in a single vertex of Δ. We provide several characterizations of such line graphs and in particular show that a graph is a line graph if and only if it does not contain one of the 32 graphs, all of which
Hans Cuypers
wiley +1 more source
Invariant algebras and completely reducible representations [PDF]
We give a general construction of affine noetherian algebras with the property that every finite dimensional representation is completely reducible. Starting from enveloping algebras of semi simple Lie algebras in characteristic zero we obtain explicit ...
Kraft, Hanspeter, Small, Lance W.
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Regional heavy rainfall events (RHREs) in Guangdong, South China, during 1961–2025 are reassessed using an improved strength index that integrates rainfall intensity, spatial extent and duration. Results reveal a post‐1991 shift towards more frequent and spatially extensive strong and extreme events, with June showing the most pronounced ...
Wei Liu +6 more
wiley +1 more source
Generating Helical Polymorphic Beams Using Dielectric Metasurfaces
Helix‐shaped polymorphic beams are optical fields whose intensity maxima spiral around the propagation axis, enabling particle manipulation through attractive or repulsive forces. Traditionally requiring expensive spatial light modulators, metasurfaces now provide a compact, cost‐effective alternative. This work demonstrates general helical polymorphic
Maryam Setareh +3 more
wiley +1 more source
Peskine Sixfolds and Debarre–Voisin Fourfolds With Associated Cubic Fourfolds
ABSTRACT We develop the notion of Peskine sixfolds with associated K3 surfaces and cubic fourfolds and work out numerical conditions for when these associations occur. In discriminant 24, the first family for which there is an associated cubic fourfold, we identify the cubic explicitly.
Corey Brooke +3 more
wiley +1 more source
Invariants of automorphic lie algebras [PDF]
Automorphic Lie Algebras arise in the context of reduction groups introduced in the late 1970s [35] in the field of integrable systems. They are subalgebras of Lie algebras over a ring of rational functions, denied by invariance under the action of a ...
Knibbeler, Vincent
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Purely Coclosed G2‐Structures on Nilmanifolds—II
ABSTRACT This paper completes the classification of seven‐dimensional nilpotent Lie groups endowed with a left‐invariant purely coclosed G2$\text{G}_2$‐structure, initiated in Bazzoni et al. [Mathematische Nachrichten 296 no. 6 (2023): 2236–2257], the authors provided the classification of decomposable seven‐dimensional nilpotent Lie groups and of the ...
Giovanni Bazzoni, Giorgia Petracci
wiley +1 more source
ABSTRACT Nowadays, a substantial portion of investigations concerning the symmetry analysis of differential equations predominantly adhere to a framework comprising the following key procedures: (i) the derivation of symmetries, (ii) the determination of an optimal system, (iii) the utilization of these symmetries to construct invariants or ...
A. Paliathanasis +2 more
wiley +1 more source
Fragmentation–Coagulation Processes With Advection or Diffusion in Space
ABSTRACT In this paper, we consider a continuous fragmentation–coagulation model in which the reacting particles can be transported in physical space through either advection or diffusion. We prove new results on the generation of C0$$ {C}_0 $$‐semigroups with parameter and use them to show that the abstract Cauchy problem associated with a more ...
Jacek Banasiak, Nduduzo Majozi
wiley +1 more source
Order preserving limits of finite-dimensional nest algebras. [PDF]
We introduce order conserving embeddings as a more general form of order preserving embeddings between finite dimensional nest algebras. The structure of these embeddings is determined, in terms of order indecomposable decompositions, and they are shown ...
Alan Hopenwasser +3 more
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