Johan Oinert

activity

20072026

most citedSkew Category Algebras Associated with Partially Defined Dynamical Systems

29 citations · 67 across the 14 of their papers we have counts for

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Showing math.RAShow all

17 papers · 1 filter

math.RA2026

Bimodules in differential polynomial rings

Johan Öinert

We study the $R$ -sub-bimodule structure of differential polynomial rings $R [x; δ]$ by introducing the notion of strong simplicity, requiring each nonzero $R$ -sub-bimodule of $R[x;δ]…

math.RA2026

Central idempotents in group-graded rings

Johan Öinert

Let $G$ be a group and let $R$ be a $G$ -graded ring. We show that every nonzero central idempotent in $R$ has finite support group in two broad settings: when $G$ is abelian, and w…

math.RA2025

The rank condition and strong rank conditions for Ore extensions

Karl Lorensen, Johan Öinert

Let $R$ be a ring, $σ : R \to R$ a ring endomorphism, and $δ : R \to R$ a $σ$ -derivation. We establish that the Ore extension $R [x; σ, δ]$ satisfies the rank condition if and only if $R$ d…

math.RA2024★ 2 cited

Ore Extensions of Abelian Groups with Operators

Per Bäck, Patrik Lundström, Johan Öinert +1

Given a set $A$ and an abelian group $B$ with operators in $A$ , in the sense of Krull and Noether, we introduce the Ore group extension $B [x; σ_{B}, δ_{B}]$ as the additive group $B[x]…

math.RA2022

Simplicity of Leavitt path algebras via graded ring theory

Patrik Lundström, Johan Öinert

Suppose that $R$ is an associative unital ring and that $E = (E^{0}, E^{1}, r, s)$ is a directed graph. Utilizing results from graded ring theory we show, that the associated Leavitt path a…

math.RA2020

Strongly graded Leavitt path algebras

Patrik Lundström, Johan Öinert

Let $R$ be a unital ring, let $E$ be a directed graph and recall that the Leavitt path algebra $L_{R} (E)$ carries a natural $Z$ -gradation. We show that $L_{R} (E)$ is strongly…