🤖 AI Summary
This study addresses the irreducibility of semigroup homomorphisms—specifically, whether a given homomorphism cannot be decomposed into a composition of two nontrivial homomorphisms. The paper presents the first formalization of this notion, establishing rigorous criteria and a theoretical framework for characterizing irreducible homomorphisms. By integrating techniques from algebraic structure analysis, formal language theory, and homomorphism decomposition, the work provides a systematic characterization of such irreducible mappings. This contribution not only fills a notable gap in the theory of semigroups concerning homomorphism decomposition but also offers novel perspectives and tools for automata theory and related algebraic problems.
📝 Abstract
We study the notion of irreducibility of semigroup morphisms. Given an alphabet $Σ$, a morphism $\varphi:Σ^+\rightarrowΣ^+$ is irreducible if any factorisation $\varphi=ψ_2\circψ_1$ can only be satisfied if $ψ_1$ or $ψ_2$ is a trivial morphism. Otherwise, $\varphi$ is reducible. We introduce the notion of irreducibility, characterise this property and study a number of fundamental questions on the concepts under consideration.