arXiv math/94032201994-03-15math.LOmath.RA

A combinatorial principle equivalent to the existence of non-free Whitehead groups

Paul C. Eklof, Saharon Shelah

发表信息：: Contemp. Math. 171 (1994), 79--98

英文摘要：

As a consequence of identifying the principle described in the title, we prove that for any uncountable cardinal lambda, if there is a lambda-free Whitehead group of cardinality lambda which is not free, then there are many ``nice'' Whitehead groups of cardinality lambda which are not free.

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