English
Related papers

Related papers: An Analytic Novikov Conjecture for Semigroups

200 papers

This paper develops a novel operator theoretic framework to study the contraction properties of Markov semigroups with respect to a general class of Kantorovich semi-distances, which notably includes Wasserstein distances. The rather simple…

Probability · Mathematics 2026-03-04 Pierre Del Moral , Mathieu Gerber

In this paper, we systematically study generalized Markov numbers arising from semigroups of reduced integer matrices. This construction allows us to find these numbers by counting perfect matchings of a new family of bipartite graphs,…

Combinatorics · Mathematics 2026-04-21 Oleg Karpenkov , Yefei Ma

Let $W$ be a finite Coxeter group and $\Omega$ be its $W$-graph algebra as defined by Gyoja. The author's previous paper \cite{hahn2016wgraphs} considered this algebra in some detail, proposed, and proved in some small cases the $W$-graph…

Representation Theory · Mathematics 2017-07-11 Johannes Hahn

In this article, we prove Neveu decomposition for the action of the locally compact amenable semigroup of positive contractions on semifinite von Neumann algebras and thus, it entirely resolves the problem for the actions of arbitrary…

Operator Algebras · Mathematics 2023-08-29 Panchugopal Bikram , Diptesh Saha

The aim of this paper is to propose an extension of the Wilf conjecture to semimodules over a numerical semigroup through a new approach toward the solution of the Wilf conjecture on numerical semigroups. The key point is the introduction…

Combinatorics · Mathematics 2021-06-18 Patricio Almirón , Julio José Moyano-Fernández

We provide a reduction in the classification problem for non-compact, homogeneous, Einstein manifolds. Using this work, we verify the (Generalized) Alekseevskii Conjecture for a large class of homogeneous spaces.

Differential Geometry · Mathematics 2016-05-27 Michael Jablonski , Peter Petersen

In this paper, we define a new structure analogous to group, called partial group. This structure concerns the partial stability by the composition inner law. We generalize the three isomorphism theorems for groups to partial groups.

Group Theory · Mathematics 2013-08-06 Yahya N'Dao , Adlene Ayadi

We show that the rational Novikov conjecture for a group $\Gamma$ of finite homological type follows from the mod 2 acyclicity of the Higson compactifcation of an E$\Gamma$. We then show that for groups of finite asymptotic dimension the…

Geometric Topology · Mathematics 2007-05-23 A. Dranishnikov , S. Ferry , S. Weinberger

A proof of Thompson's conjecture for real semi-simple Lie groups has been given by Kapovich, Millson, and Leeb. In this note, we give another proof of the conjecture by using a theorem of Alekseev, Meinrenken, and Woodward from symplectic…

Symplectic Geometry · Mathematics 2007-05-23 Jiang-Hua Lu , Sam Evens

We discuss some new results concerning Gap Conjecture on group growth and present a reduction of it (and its *-version) to several special classes of groups. Namely we show that its validity for the classes of simple groups and residually…

Group Theory · Mathematics 2012-09-19 Rostislav Grigorchuk

We develop a structure theory of connected solvable spherical subgroups in semisimple algebraic groups. Based on this theory, we obtain an explicit classification of all such subgroups up to conjugation.

Group Theory · Mathematics 2012-01-24 Roman Avdeev

The Alperin weight conjecture has been reduced to simple groups by Navarro and Tiep. In this paper, we investigate the Navarro Alperin weight conjecture, which includes Galois automorphisms and group automorphisms in comparison with the…

Representation Theory · Mathematics 2026-04-23 Zhicheng Feng , Qulei Fu , Yuanyang Zhou

We prove that the approximation conjecture of Luck holds for all amenable groups in the complex group algebra case. This result was previously proved by Dodziuk, Linnell, Mathai, Schick and Yates under the assumption that the group is…

Functional Analysis · Mathematics 2016-09-07 Gabor Elek

We associate to any irreducible germ S of complex quasi-ordinary hypersurface an analytically invariant semigroup. We deduce a direct proof (without passing through their embedded topological invariance) of the analytical invariance of the…

Complex Variables · Mathematics 2007-05-23 Patrick Popescu-Pampu

In this version small mistakes are corrected and the exposition is changed as suggested by the referee (to appear in Canadian Journal of Mathematics). The first main result of the paper is a criterion for a partially commutative group $\GG$…

Group Theory · Mathematics 2008-07-28 Montserrat Casals-Ruiz , Ilya V. Kazachkov

We construct new examples of non-nil algebras with any number of generators, which are direct sums of two locally nilpotent subalgebras. As all previously known examples, our examples are contracted semigroup algebras and the underlying…

Rings and Algebras · Mathematics 2007-05-23 Vesselin Drensky , Lakhdar Hammoudi

In this paper we introduce the concept of corner element of a generalized numerical semigroup, which extends in a sense the idea of conductor of a numerical semigroup to generalized numerical semigroups in higher dimensions. We present…

Group Theory · Mathematics 2022-01-19 Matheus Bernardini , Wanderson Tenório , Guilherme Tizziotti

In this paper we introduce the notion of extension of a numerical semigroup. We provide a characterization of the numerical semigroups whose extensions are all arithmetic and we give an algorithm for the computation of the whole set of…

Commutative Algebra · Mathematics 2020-03-31 Ignacio Ojeda , José Carlos Rosales

Let $G$ be a reductive algebraic group---possibly non-connected---over a field $k$ and let $H$ be a subgroup of $G$. If $G= GL_n$ then there is a degeneration process for obtaining from $H$ a completely reducible subgroup $H'$ of $G$; one…

Group Theory · Mathematics 2020-11-11 Michael Bate , Benjamin Martin , Gerhard Roehrle

The descent method is one of the approaches to study the Brauer--Manin obstruction to the local--global principle and to weak approximation on varieties over number fields, by reducing the problem to ``descent varieties''. In recent lecture…

Algebraic Geometry · Mathematics 2026-01-21 Nguyen Manh Linh