A characterization of Ext(G,Z) assuming V=L

dc.creatorShelah, Saharon
dc.creatorStrüngmann, Lutz
dc.date2006-09-22
dc.date.accessioned2026-07-07T07:25:08Z
dc.date.available2026-07-07T07:25:08Z
dc.descriptionIn this paper we complete the characterization of Ext(G,Z) under Godel's axiom of constructibility for any torsion-free abelian group G . In particular, we prove in (V=L) that, for a singular cardinal nu of uncountable cofinality which is less than the first weakly compact cardinal and for every sequence of cardinals (nu_p : p in P) satisfying nu_p <= 2^{nu}, there is a torsion-free abelian group G of size nu such that nu_p equals the p-rank of Ext(G,Z) for every prime p and 2^{nu} is the torsion-free rank of Ext(G,Z).
dc.identifierhttps://arxiv.org/abs/math/0609638
dc.identifierhttp://arxiv.org/abs/math/0609638
dc.identifierFund. Math. 193 No. 2 (2007) 141--151
dc.identifier.urihttp://salesiana.dossiersoluciones.com/handle/123456789/116622
dc.subjectLogic
dc.subjectGroup Theory
dc.titleA characterization of Ext(G,Z) assuming V=L
dc.typetext

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