Results 61 to 70 of about 4,735 (227)
Oppenheim–Schur inequalities for causal products
Bulletin of the London Mathematical Society, Volume 58, Issue 6, June 2026.Abstract We establish a class of Oppenheim–Schur‐type inequalities for the convolutional Jury product of positive semidefinite matrices. These results extend the classical Schur and Oppenheim inequalities associated with the Hadamard product to a causal convolutional setting.
Dominique Guillot +2 more
wiley +1 more source
Fraïssé theory for Cuntz semigroups
Journal of AlgebraWe introduce a Fraïssé theory for abstract Cuntz semigroups akin to the theory of Fraïssé categories developed by Kubiś. In particular, we show that any (Cuntz) Fraïssé category has a unique Fraïssé limit which is both universal and homogeneous. We also give several examples of such categories and compute their Fraïssé limits. During our investigations,
Cantier, Laurent, Vilalta Vila, Eduard
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Theory of decomposition in semigroups
Advances in Mathematics, 1985 Let S be an Abelian Hausdorff topological semigroup with a unit element e. The authors call S Hungarian if (i) S is first countable, (ii) the set of associates of any element x (a is an associate of b, \(a\sim b\), if \(a=bc\) and \(b=ad\) for some c,d) is closed, (iii) the set of divisors of any element of the factor semigroup \(S^*(=S/\sim)\) is a ...
Ruzsa, Imre Z, Székely, Gábor J
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The Cuntz semigroup of continuous functions into certain simple C*-algebras [PDF]
, 2011 Peer ...
AARON TIKUISIS, Tikuisis, A.
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A Parameter Property of Classical Solutions of Cauchy Problems
Abstract and Applied Analysis, 2014 This work is concerned with the abstract Cauchy problems that depend on parameters. The goal is to study continuity in the parameters of the classical solutions of the Cauchy problems.
Min He
doaj +1 more source
Maximum number of zeroes of polynomials on weighted projective spaces over a finite field
Bulletin of the London Mathematical Society, Volume 58, Issue 6, June 2026.Abstract We compute the maximum number of rational points at which a homogeneous polynomial can vanish on a weighted projective space over a finite field, provided that the first weight is equal to 1. This solves a conjecture by Aubry, Castryck, Ghorpade, Lachaud, O'Sullivan and Ram, which stated that a Serre‐like bound holds with equality for weighted
Jade Nardi, Rodrigo San‐José
wiley +1 more source
On quasi-contractivity of C 0-semigroups on Banach spaces
, 2004 A basic result in semigroup theory states that every C-0-semigroup is quasi-contractive with respect to some appropriately chosen equivalent norm. This paper contains a counterpart of this well-known fact.
Matolcsi, Máté
core +1 more source
On an equivalence between regular ordered Γ-semigroups and regular ordered semigroups
Open Mathematics, 2020 In this paper, we develop a technique which enables us to obtain several results from the theory of Γ-semigroups as logical implications of their semigroup theoretical analogues.
Çullhaj Fabiana, Krakulli Anjeza
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Isotopy and equivalence of knots in 3‐manifolds
Journal of the London Mathematical Society, Volume 113, Issue 6, June 2026.Abstract Two knots K$K$ and J$J$ in S3$S^3$ are isotopic if and only if they are related by an orientation‐preserving diffeomorphism of S3$S^3$. This claim follows from the fact that any orientation‐preserving self‐diffeomorphism of S3$S^3$ is isotopic to the identity. We show that this same idea applies to any prime oriented closed 3‐manifold.
Paolo Aceto +4 more
wiley +1 more source
Positive Solutions for the Initial Value Problem of Fractional Evolution Equations
Abstract and Applied Analysis, 2013 By using the fixed point theorems and the theory of analytic semigroup, we investigate the existence of positive mild solutions to the Cauchy problem of Caputo fractional evolution equations in Banach spaces.
He Yang, Yue Liang
doaj +1 more source