The uniform dimension of a monoid with applications to graph algebras

Gespeichert in:
Bibliographische Detailangaben
Titel: The uniform dimension of a monoid with applications to graph algebras
Autoren: Luiz Gustavo Cordeiro, Daniel Gonçalves, Roozbeh Hazrat
Quelle: Journal of Algebra. 682:31-59
Publication Status: Preprint
Verlagsinformationen: Elsevier BV, 2025.
Publikationsjahr: 2025
Schlagwörter: Rings and Algebras (math.RA), Mathematics - Operator Algebras, FOS: Mathematics, Mathematics - Rings and Algebras, Operator Algebras (math.OA), 16S88
Beschreibung: We adapt Goldie's concept of uniform dimensions from module theory over rings to $Γ$-monoids. A $Γ$-monoid $M$ is said to have uniform dimension $n$ if $n$ is the largest number of pairwise incomparable nonzero $Γ$-order ideals contained in $M$. Specializing to the talented monoid of a graph, we show that the uniform dimension provides a rough measure of how the graph branches out. Since for any order ideal $I$, its orthogonal ideal $I^\perp$ is the largest ideal incomparable to $I$, we study the notions of orthogonality and regularity, particularly when $I^{\perp\perp}=I$. We show that the freeness of the action of $\mathbb Z$ on the talented monoid of a graph is preserved under quotienting by a regular ideal. Furthermore, we determine the underlying hereditary and saturated sets that generate these ideals. These results unify recent studies on regular ideals of the corresponding Leavitt path algebras and graph $C^*$-algebras. We conclude that for graphs $E$ and $F$, if there is a $\mathbb Z$-monoid isomorphism $T_E\cong T_F$, then there is a one-to-one correspondence between the regular ideals of the associated Leavitt path algebras $L_K(E)$ and $L_K(F)$ (and similarly, $C^*(E)$ and $C^*(F)$). Since the talented monoid $T_E$ is the positive cone of the graded Grothendieck group $K_0^{gr}(L_K(E))$, this provides further evidence supporting the Graded Classification Conjecture.
Publikationsart: Article
Sprache: English
ISSN: 0021-8693
DOI: 10.1016/j.jalgebra.2025.05.042
DOI: 10.48550/arxiv.2502.11226
Zugangs-URL: http://arxiv.org/abs/2502.11226
Rights: Elsevier TDM
arXiv Non-Exclusive Distribution
Dokumentencode: edsair.doi.dedup.....74b070454e49ff2f1812e355fff1fea7
Datenbank: OpenAIRE
Beschreibung
Abstract:We adapt Goldie's concept of uniform dimensions from module theory over rings to $Γ$-monoids. A $Γ$-monoid $M$ is said to have uniform dimension $n$ if $n$ is the largest number of pairwise incomparable nonzero $Γ$-order ideals contained in $M$. Specializing to the talented monoid of a graph, we show that the uniform dimension provides a rough measure of how the graph branches out. Since for any order ideal $I$, its orthogonal ideal $I^\perp$ is the largest ideal incomparable to $I$, we study the notions of orthogonality and regularity, particularly when $I^{\perp\perp}=I$. We show that the freeness of the action of $\mathbb Z$ on the talented monoid of a graph is preserved under quotienting by a regular ideal. Furthermore, we determine the underlying hereditary and saturated sets that generate these ideals. These results unify recent studies on regular ideals of the corresponding Leavitt path algebras and graph $C^*$-algebras. We conclude that for graphs $E$ and $F$, if there is a $\mathbb Z$-monoid isomorphism $T_E\cong T_F$, then there is a one-to-one correspondence between the regular ideals of the associated Leavitt path algebras $L_K(E)$ and $L_K(F)$ (and similarly, $C^*(E)$ and $C^*(F)$). Since the talented monoid $T_E$ is the positive cone of the graded Grothendieck group $K_0^{gr}(L_K(E))$, this provides further evidence supporting the Graded Classification Conjecture.
ISSN:00218693
DOI:10.1016/j.jalgebra.2025.05.042