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Related papers: Takahasi semigroups

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The paper deals with the long-term behavior of positive operator semigroups on spaces of bounded functions and of signed measures, which have applications to parabolic equations with unbounded coefficients and to stochastic analysis. The…

Functional Analysis · Mathematics 2021-11-09 Moritz Gerlach , Jochen Glück , Markus Kunze

Coclass theory has been a highly successful approach towards the investigation and classification of finite nilpotent groups. Here we suggest a similar approach for finite nilpotent semigroups. This differs from the group theory setting in…

Rings and Algebras · Mathematics 2014-04-17 Andreas Distler , Bettina Eick

We give quantitative bounds for the number of quasi-integral points in orbits of semigroups of rational maps under some conditions, generalizing previous work of L. C. Hsia and J. Silverman (2011) for orbits generated by the iterations of…

Number Theory · Mathematics 2019-05-13 Jorge Mello

We prove a Desch-Schappacher type perturbation theorem for one-parameter semigroups on Banach spaces which are not strongly continuous for the norm, but possess a weaker continuity property. In this paper we chose to work in the framework…

Functional Analysis · Mathematics 2021-01-01 Christian Budde , Bálint Farkas

We introduce the concept of a restriction semigroupoid S, which unifies the notion of restriction semigroups and restriction categories within a single structure. We prove a representation theorem, showing that every restriction…

Rings and Algebras · Mathematics 2025-04-30 Rafael Haag , Wesley G. Lautenschlaeger , Thaísa Tamusiunas

We develop a theory of type semigroups for arbitrary twisted, not necessarily Hausdorff \'etale groupoids. The type semigroup is a dynamical version of the Cuntz semigroup. We relate it to traces, ideals, pure infiniteness, and stable…

Operator Algebras · Mathematics 2025-03-28 Bartosz K. Kwaśniewski , Ralf Meyer , Akshara Prasad

We improve on earlier results on the closure under free products of the class of automaton semigroups. We consider partial automata and show that the free product of two self-similar semigroups (or automaton semigroups) is self-similar (an…

Group Theory · Mathematics 2025-09-01 Tara Macalister Brough , Jan Philipp Wächter , Janette Welker

We enumerate certain geometric equivalence classes of subgraphs induced by Hamiltonian paths and cycles in complete graphs. Said classes are orbits under the action of certain direct products of dihedral and cyclic groups on sets of strings…

Combinatorics · Mathematics 2021-08-31 Samuel Herman , Eirini Poimenidou

We give a proof, based on thermodynamic formalism, of a theorem in bounded cohomology extending a foundational result of Burger and Monod: if $\Gamma$ is an irreducible uniform lattice in a non-compact connected semisimple Lie group of real…

Dynamical Systems · Mathematics 2026-03-31 Pablo D. Carrasco , Federico Rodriguez-Hertz

For a mixing shift of finite type, the associated automorphism group has a rich algebraic structure, and yet we have few criteria to distinguish when two such groups are isomorphic. We introduce a stabilization of the automorphism group,…

Dynamical Systems · Mathematics 2020-01-28 Yair Hartman , Bryna Kra , Scott Schmieding

Consider a one-ended word-hyperbolic group. If it is the fundamental group of a graph of free groups with cyclic edge groups then either it is the fundamental group of a surface or it contains a finitely generated one-ended subgroup of…

Group Theory · Mathematics 2014-11-11 Henry Wilton

The question of computing the group complexity of finite semigroups and automata was first posed in K. Krohn and J. Rhodes, \textit{Complexity of finite semigroups}, Annals of Mathematics (2) \textbf{88} (1968), 128--160, motivated by the…

Group Theory · Mathematics 2008-12-19 Karsten Henckell , John Rhodes , Benjamin Steinberg

We study congruences on the partial automorphism monoid of a finite rank free group action. We give a decomposition of a congruence on this monoid into a Rees congruence, a congruence on a Brandt semigroup and an idempotent separating…

Rings and Algebras · Mathematics 2020-02-04 Matthew D G K Brookes

Schmidt's subspace theorem in terms of Seshadri constants for closed subschemes in subgeneral position has been already developed sharply. We derive our theorem for numerically equivalent ample divisors by dint of the above theory step by…

Number Theory · Mathematics 2025-06-16 GuanHeng Zhao

Let $\Omega$ be an operator semigroup with generator $A$ in a sequentially complete locally convex topological vector space $E$. For a semigroup with generator $A+D$, where $D$ is a bounded linear operator on $E$, two integral equations are…

Functional Analysis · Mathematics 2007-06-20 A. Yurachkivsky , A. Zhugayevych

Groups, in which every subgroup containing some fixed primary cyclic subgroup has a complement, are investigated.

Group Theory · Mathematics 2007-10-08 O. O. Trebenko

Stallings folding theory is modified, using double coset representatives, and to applied to the study of subgroups of amalgamated products of finite rank free groups. As a first application the subgroup membership problem for such groups is…

Group Theory · Mathematics 2013-05-22 Andrew Duncan , Elizaveta Frenkel

Restriction is a natural quasi-order on $d$-way tensors. We establish a remarkable aspect of this quasi-order in the case of tensors over a fixed finite field -- namely, that it is a well-quasi-order: it admits no infinite antichains and no…

Algebraic Geometry · Mathematics 2025-09-03 Andreas Blatter , Jan Draisma , Filip Rupniewski

We present some fundamental results on (possibly nonlinear) algebraic semigroups and monoids. These include a version of Chevalley's structure theorem for irreducible algebraic monoids, and the description of all algebraic semigroup…

Algebraic Geometry · Mathematics 2013-12-23 Michel Brion

A $biased\ graph$ is a pair $(G,\mathcal{B})$, where $G$ is a graph and $\mathcal{B}$ is a collection of `balanced' circuits of $G$ such that no $\Theta$-subgraph of $G$ contains precisely two balanced circuits. We prove a Ramsey-type…

Combinatorics · Mathematics 2018-03-28 Peter Nelson , Sophia Park