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19922007
most citedOn Whitehead precovers

12 citations · 25 across the 17 of their papers we have counts for

collaborators

17 papers

math.LO2007

Test Groups for Whitehead Groups

Paul C. Eklof, Laszlo Fuchs, Saharon Shelah

We consider the question of when the dual of a Whitehead group is a test group for Whitehead groups. This turns out to be equivalent to the question of when the tensor product of t…

math.LO2004

Hereditarily separable groups and monochromatic uniformization

Paul C. Eklof, Alan H. Mekler, Saharon Shelah

We give a combinatorial equivalent to the existence of a non-free hereditarily separable group of cardinality aleph_1. This can be used, together with a known combinatorial equival…

math.LO2004

On the cogeneration of cotorsion pairs

Paul C. Eklof, Saharon Shelah, Jan Trlifaj

Let R be a Dedekind domain. Enochs' solution of the Flat Cover Conjecture was extended as follows: (*) If C is a cotorsion pair generated by a class of cotorsion modules, then C is…

math.LO2003

The structure of Ext(A,Z) and GCH: possible co-Moore spaces

Paul C. Eklof, Saharon Shelah

We consider what Ext(A,Z) can be when A is torsion-free and Hom(A,Z)=0. We thereby give an answer to a question of Golasinski and Goncalves which asks for the divisible Abelian gro…

math.LO2000★ 12 cited

Whitehead modules over large principal ideal domains

Paul C. Eklof, Saharon Shelah

We consider the Whitehead problem for principal ideal domains of large size. It is proved, in ZFC, that some p.i.d.'s of size >= aleph_{2} have non-free Whitehead modules even thou…

math.LO2000★ 12 cited

On Whitehead precovers

Paul C. Eklof, Saharon Shelah

It is proved undecidable in ZFC + GCH whether every Z-module has a^{perp} {Z}-precover.