Results 11 to 20 of about 218 (97)
Maximal independence and regularity of Al/Si distributions in disordered phyllosilicates 2:1. [PDF]
Acta Crystallogr A Found AdvThe distribution of aluminium cations in disordered phyllosilicates is analysed according to the concepts of maximal independence and regularity.As an extension of previous works, we analyse regularity in disordered Al/Si distributions in phyllosilicates 2:1. The method is based on an analysis of maximal independent sets in a labelled quotient graph of
Moreira de Oliveira M, Eon JG.
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Compact Manifolds With Unbounded Nilpotent Fundamental Groups and Positive Ricci Curvature
Communications on Pure and Applied Mathematics, EarlyView.ABSTRACT It follows from the work of Kapovitch and Wilking that a closed manifold with nonnegative Ricci curvature has a uniformly almost nilpotent fundamental group. Leftover questions and conjectures, have asked if in this context the fundamental group is actually uniformly almost abelian. The main goal of this work is to construct examples (Mk9,gk)$(
Elia Bruè, Aaron Naber, Daniele Semola
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Catalan Bounds for Symmetric Strength‐Two Orthogonal Arrays
Journal of Combinatorial Designs, EarlyView.ABSTRACT A Hamming shell construction is a two‐level array obtained by taking every binary vector of a given Hamming weight a prescribed number of times, for each weight in turn. Such arrays are invariant under all permutations of the factors, and they are strength‐two orthogonal arrays exactly when the multiplicities satisfy three linear constraints ...
Ruwan C. Karunanayaka
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Classifying Equidistant Permutation Codes
Journal of Combinatorial Designs, EarlyView.ABSTRACT A permutation code of length n $n$ is a set of codewords, each of which contains every symbol of a set of size n $n$ exactly once. A permutation code in which any two distinct codewords differ in the same number of coordinates is called equidistant and that number is called the distance.
Patric R. J. Östergård +1 more
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A Boothby–Wang Construction in Generalized Contact Geometry
Mathematische Nachrichten, EarlyView.ABSTRACT We establish a generalized analogue of the Boothby–Wang theorem in generalized contact geometry, along with related results. We present a general method for constructing examples of generalized contact structures that are not of Poon–Wade type, and even examples that fail to be generalized contact structures.
Debjit Pal
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Graded Differential Polynomial Rings
Mathematische Nachrichten, EarlyView.ABSTRACT We study differential polynomial rings R[t;δ]$R[t;\delta]$ over Γ$\Gamma$‐graded rings, where Γ$\Gamma$ is an arbitrary group. We show that R[t;δ]$R[t;\delta]$ admits a Γ$\Gamma$‐grading compatible with that of R$R$ if and only if δ$\delta$ is a γ$\gamma$‐derivation for some γ∈CΓ(ΓR)$\gamma \in C_\Gamma (\Gamma _R)$, and that this grading is ...
Yassine Ait Mohamed
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An uncomplicated introduction to representational measurement theory
British Journal of Mathematical and Statistical Psychology, EarlyView.Abstract Measurement in psychology is often associated with psychometrics. Despite the theoretical insights afforded by psychometric methods, they represent only a restricted range of possible measurement approaches in the social sciences. Representational measurement theory (RMT) generalizes the logic of measurement developed in the physical sciences ...
Vithor Rosa Franco +3 more
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On the additive image of zeroth persistent homology
Transactions of the London Mathematical Society, Volume 13, Issue 1, December 2026.Abstract For a category X$X$ and a finite field F$F$, we study the additive image of the functor H0(−;F)∗:rep(X,Top)→rep(X,VectF)$\operatorname{H}_0(-;F)_* \colon \operatorname{rep}(X, \mathbf {Top}) \rightarrow \operatorname{rep}(X, \mathbf {Vect}_F)$, or equivalently, of the free functor rep(X,Set)→rep(X,VectF)$\operatorname{rep}(X, \mathbf {Set ...
Ulrich Bauer +3 more
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Rational points on even‐dimensional Fermat cubics
Transactions of the London Mathematical Society, Volume 13, Issue 1, December 2026.Abstract We show that even‐dimensional Fermat cubic hypersurfaces are rational over any field of characteristic not equal to three, by constructing explicit rational parameterizations with polynomials of low degree. As a byproduct of our rationality constructions, we obtain estimates for the number of their rational points over a number field and ...
Alex Massarenti
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On the automorphisms of the power semigroups of a numerical semigroup
Transactions of the London Mathematical Society, Volume 13, Issue 1, December 2026.Abstract If H$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
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