Abstract
AssumeV =L andλ is regular smaller than the first weakly compact cardinal. Under those circumstances and with arbitrary requirements on the structure of Ext (G, ℤ) (under well known limitations), we construct an abelian groupG of cardinalityλ such that for noG′ ⊆G, |G′| <λ isG/G′ free and Ext (G, ℤ) realizes our requirements.
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Deceased.
Partially supported by NSERC.
Partially supported by the United States — Israel Binational Science Foundation. Publication No. 314.
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Mekler, A., Rosłanowski, A. & Shelah, S. On thep-rank of Ext. Isr. J. Math. 112, 327–356 (1999). https://doi.org/10.1007/BF02773487
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DOI: https://doi.org/10.1007/BF02773487