M. Dugas

collaborators

2 papers

math.GR2019

$ℵ_{k}$ -free cogenerators

Manfred Dugas, Daniel Herden, Saharon Shelah

We prove in ZFC that an abelian group $C$ is cotorsion if and only if $Ext (F, C) = 0$ for every $ℵ_{k}$ -free group $F$ , and discuss some consequences and related r…

math.RA2017

Local automorphisms of finitary incidence algebras

Jordan Courtemanche, Manfred Dugas, Daniel Herden

Let $R$ be a commutative, indecomposable ring with identity and $(P, \leq)$ a partially ordered set. Let $F I (P)$ denote the finitary incidence algebra of $(P, \leq)$ over $R$ . We will…

ℵk​-free cogenerators

Local automorphisms of finitary incidence algebras

$ℵ_{k}$ -free cogenerators